Is The Paleo Diet Based On A Myth?

Are Starchy Foods Bad For Us? 

Author: Dr. Stephen Chaney

the paleo dietThe Paleo Diet is still very popular. And it does have its good points. It is a whole food diet. It eliminates sodas, junk foods, and highly processed foods. Any diet that does that can’t be all bad.

But is it unnecessarily restrictive? It eliminates starchy foods like grains, beans, peas, and corn. It is true that widespread consumption of these foods did not occur until after the agricultural revolution some 12,000 years ago. Our paleolithic ancestors probably did not consume significant quantities of these foods.

But did they consume other starchy foods? Our ideas about this have come primarily from comparing the diets of modern man with the diets of the few primitive hunter-gatherer populations that currently exist in our world. Based on that comparison, some Paleo advocates have concluded that the paleolithic diet contained few, if any, starchy foods.

More importantly, some Paleo advocates have gone a step further to assert that our bodies are not designed to eat starchy foods. They claim that foods like grains, legumes, corn, and potatoes are bad for us. They should be avoided.

How can we test whether these claims are true? After all, we don’t have any way of directly determining whether our paleolithic ancestors ate starchy foods or not. Or do we? That question is the topic of a new study (JA Fellows et al, PNAS, 118 No. 20 e2021655118 I will share with you today.

But first I need to acquaint you with what starch is and how we digest it. Once again, it is time for Biochemistry 101.

Biochemistry 101

professor owlStarch is simply a long polymer of glucose molecules. Digestion of starch starts in our mouth. Our saliva contains an enzyme called alpha-amylase that breaks the bond between adjacent glucose molecules. Alpha-amylase breaks starch down sequentially, first to maltodextrin (a shorter polymer of glucose molecules), then to maltose (two glucose molecules), and finally to glucose.

[Note: The nutrition gurus that tell you to read labels and avoid foods with maltodextrin are ignoring the fact that we produce maltodextrin naturally whenever we digest starch in the foods we eat.]

All humans contain the alpha-amylase gene. Simply put, that means that all humans have the potential to digest starchy foods.

However, not all humans have the same number of copies of the alpha-amylase gene. When we habitually consume a diet containing starchy foods, our bodies duplicate the alpha-amylase gene until our saliva contains enough alpha-amylase to easily digest the amount of starchy foods we are consuming. Simply put, that means our bodies are designed to easily adapt to the amount of starchy foods in our diet.

Most modern human populations have between six and 30 copies of the alpha-amylase gene. Our saliva contains a lot of alpha-amylase. However, the few primitive hunter-gatherer societies that still exist in our world have only two or three copies of the alpha-amylase gene. Their saliva contains very little alpha-amylase.

It is this difference that has led to the hypothesis that our paleolithic ancestors did not possess salivary alpha-amylase, which implies they didn’t eat starchy foods. This hypothesis also assumes that humans only began producing significant quantities of salivary alpha-amylase after the agricultural revolution when starchy foods like grains, rice, and beans became widely available.

This hypothesis is one of the central tenets of the Paleo diet. But we need to remember that it is just a hypothesis. It has not been directly tested because we thought there was no way to determine the starch content of the paleolithic diet – until now. However, before we get to the study that explodes this hypothesis, I want to revisit the Paleo Diet myths I described in an earlier issue of “Health Tips From The Professor”. I call this next section “Unicorns And The Paleo Diet”.

Unicorns And the Paleo Diet

the paleo diet and unicornsI titled this section “Unicorns and the Paleo Diet” because both are myths. In fact, the Paleo Diet is based on several myths.

Myth #1: Our ancestors all had the same diet. What we currently know as the Paleo diet is based on the diets of a few primitive hunter-gatherer societies that still exist in some regions of the world. However, when you look at the data more carefully, you discover that the diet of primitive societies varies with their local ecosystems.

The “Paleo diet” is typical of ecosystems in which game is plentiful and fruits and vegetables are less abundant or are seasonal. In ecosystems where fruits and vegetables are abundant, primitive societies tend to be more gatherers than hunters. They eat more fruits and vegetables and less meat.

The assumption that starchy foods were absent in the paleolithic diet is also a myth. For some primitive societies, starchy fruits or starchy roots are a big part of their diet. In short, our paleolithic ancestors ate whatever nature provided.

Myth #2: Our genetic makeup is hardwired around the “paleolithic diet”. In fact, humans are very adaptable. We are omnivores, which means we can eat whatever nature provides. We are designed to thrive in a wide variety of ecosystems. It is this adaptability that has allowed us to expand to every nook and cranny of the world.

For example, the enzymes needed to digest grains are all inducible, which means the body can turn them on when needed. Our paleolithic ancestors may not have eaten much grain, but we can very quickly adapt to the introduction of grains into our diet. As I described above, for alpha-amylase this adaptation occurs through gene duplication.

Myth #3: Our paleolithic ancestors were healthier than modern man: It some respects, the paleolithic diet is healthy, as I mentioned above. However, we need to remember that our paleolithic ancestors rarely lived past 30 or 40. They simply did not live long enough to experience degenerative diseases like heart disease and cancer. We have no idea whether a diet that served our paleolithic ancestors well will keep us healthy into our 70s, 80s and beyond.

How Was This Study Done?

Clinical StudyThis is a fascinating study, and one that would have been impossible just a few years ago. As I have described in previous issues of “Health Tips From the Professor”, studies on our microbiome, the bacteria that inhabit our bodies, is a rapidly evolving area of research.

When we talk about our microbiome, we generally think about our gut bacteria. However, the term “microbiome” includes all the bacteria that reside in our body, including those that reside in our oral mouth.

And, like our gut bacteria, the species of bacteria that reside in our mouth are heavily dependent on the foods we eat. Specifically, there are three species of oral bacteria that thrive on starch. They possess an “amylase binding protein” that allows them to capture salivary alpha-amylase and use it to break down dietary starch so they can use it as an energy source.

Consequently, the abundance of these three bacterial species in the oral microbiome is a precise marker for the amount of starch in a person’s diet. More importantly, high throughput DNA sequencing and supercomputers have made it simple to sequence all the bacteria in the oral microbiome and quantify the relative abundance of these three bacterial species.

You are probably thinking, “That’s fine, but how could you possibly determine the abundance of those bacteria in the mouth of a paleolithic human?” Here is where it gets really interesting!

The bacteria in our mouth form biofilms on our teeth, something we refer to as plaque. If the plaque remains on our teeth long enough, it calcifies, forming what is referred to as dental calculus (tooth tartar).

In the modern world we remove dental biofilms by brushing after every meal. We remove dental plaque and tartar by semi-annual visits to the dentist. But these are recent developments. They are not something our ancestors did.

Our ancestors simply accumulated dental calculus during their lifetime. More importantly, the dental calculus excluded air and water, so it preserved the DNA of the bacteria in their oral microbiome. That was the basis of the current study.

The study was a collaboration of 50 scientists over a 7-year period. The scientists sequenced 124 oral microbiomes from humanoid species in Africa, including Neanderthals (430,000 to 40,000 years ago), Late Pleistocene (129,000 to 11,700 years ago) humans, and modern-day humans.

Bacterial DNA from modern-day humans was obtained from dental calculus obtained during routine dental cleaning procedures by practicing dentists. The older DNA samples were obtained from dental calculus in the teeth of skeletal remains. The oldest DNA sample was obtained from a Neanderthal that lived around 100,000 years ago.

For comparison they also obtained bacterial DNA from the dental calculus of chimpanzees and gorillas, man’s closest primate relatives.

The species of bacteria in the oral microbiome from all these samples were determined by high throughput sequences and computerized analysis using high speed supercomputers.

Is The Paleo Diet Based On A Myth?

Question MarkThere were three important findings from this analysis:

  1. The species of bacteria in the oral microbiome of Neanderthals and Late Pleistocene humans was much more diverse than for modern humans. This suggests that their diets were more diverse (perhaps depending on what foods were available in their environment), while modern diets have become more standardized.

2) The species of bacteria that thrive on starchy foods were remarkably constant in the oral microbiome of all human species from Neanderthals to Late Pleistocene humans to modern-day humans.

3) The species of bacteria that thrive on starchy foods were virtually absent from the oral microbiomes of our most closely related primates – chimpanzees and gorillas.

The authors concluded, “This … supports an early importance of starch-rich foods in Homo evolution.”

In other words, our paleolithic ancestors likely did eat starchy foods. Their diet may not have contained grains, rice, or beans in significant quantities. However, they consumed whatever starchy roots, fruits, and vegetables they could find.

So, is the Paleo diet based on a myth? It depends on how you phrase the question.

  • If we ask whether our paleolithic ancestors consumed grains, rice, or beans, the answer is probably, “No”. The introduction of these foods in significant quantities probably depended on the agricultural revolution that occurred thousands of years later.
  • If we ask whether our paleolithic ancestors consumed starchy foods, the answer is probably, “Yes”. The foundation of the Paleo diet was based on a myth. Their oral microbiome contained bacterial species that thrived on starchy foods. In fact, starchy foods may have been an important staple in their diet because they are more calorie dense than other fruits and vegetables.
  • If we ask whether our paleolithic ancestors were capable of thriving on a diet that included grains, rice, and beans, the answer is also probably, “Yes”. The oral bacterial species that thrive on starchy foods do so by utilizing the alpha-amylase in human saliva. This means our paleolithic ancestors likely had enough alpha-amylase in their saliva to digest and to thrive on starchy foods like grains, rice, and beans.

Are Starchy Foods Bad For Us?

Starchy FoodsIt is not just the Paleo diet. Many popular diets have villainized starchy foods. Are starchy foods as bad for us as some “experts” would have you believe?

Let’s start by identifying starchy foods. If we think in terms of whole foods, they are:

  • Root vegetables (for example, potatoes, sweet potatoes, beets, carrots, and parsnips).
  • Legumes (for example, beans, peas, and lentils).
  • Grains (for example, wheat, rye, barley, oats, and rice).
  • Winter squash (for example, acorn squash, butternut squash, hubbard squash, and pumpkin).
  • Corn

These foods are good sources of nutrients and phytonutrients. Many of them are also excellent sources of fiber, including a special type of fiber called resistant starch. (I have described the benefits of resistant starch in a previous issue of “Health Tips From the Professor”.) These are foods that definitely deserve to be part of a healthy diet.

The only drawback of starchy vegetables is that they tend to be more calorie dense than other vegetables. While this was a “plus” for our paleolithic ancestors, it is not quite as advantageous in our modern world. If you are trying to watch your calories, my advice is to incorporate these foods into your diet sparingly.

However, there is another class of starchy foods you want to avoid. Of course, I am talking about highly processed foods made from grains, legumes, and corn. They retain all the calories but lose most of the nutrients, phytonutrients, and fiber of the foods they came from.

In short, starchy whole foods are a valuable part of a healthy diet. It is the starchy processed foods made from these whole foods you want to avoid. Of course, I am talking about bread, pasta, and pastries made from refined grains and sugar.

So, how do you know which starchy foods to avoid? My advice is not to become an expert label reader. Just eat foods without labels.

The Bottom Line

One of the founding principles on which the Paleo diet is based is that our paleolithic ancestors ate very few starchy foods, and the human body really isn’t designed to handle these foods. Accordingly, the Paleo diet recommends we should avoid starchy foods like grains and legumes. This has the unfortunate effect of creating an unbalanced diet that overemphasizes meat and animal fats.

But is this founding principle correct, or is it just a myth? When you look beneath the surface, you discover that it is a hypothesis based on the diets of the few primitive hunter-gatherer populations that still exist in our world.

It has been assumed that was as good an estimate of the paleolithic diet as we could get. After all there was no way to directly determine the starch content of the paleolithic diet – until now.

In this issue of “Health Tips From the Professor” I describe a novel approach that allowed scientists to determine the species of bacteria residing in the mouth of our humanoid ancestors based on the DNA extracted from the plaque coating their teeth. (For details on how this was done, read the article above.)

What the scientists found was that all human species, including a Neanderthal who died 100,000 years ago, harbored bacteria in their mouths that thrive on starchy foods.

The scientists concluded, “This … supports an early importance of starch-rich foods in Homo evolution.” In other words, our paleolithic ancestors likely did eat starchy foods. Restricting whole grains and legumes from the Paleo diet is based on a myth. They are an important part of a healthy diet.

For more details about the study and which starchy foods are bad for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

What Is An Anti-Inflammatory Diet?

Can Diet Douse The Flames?

Author: Dr. Stephen Chaney

InflammationIf you have arthritis, colitis, bursitis, or any of the other “itis” diseases, you already know that inflammation is the enemy. Chronic, low level inflammation is also a contributing factor to heart disease, cancer, and many other diseases. Clearly, inflammation is a bad actor. It is something we want to avoid.

Obesity and diabetes are two of the biggest contributors to inflammation, but does diet also play a role? With all the anti-inflammation diets circulating on the internet, you would certainly think so. How good is the evidence that certain foods influence inflammation, and what does an anti-inflammatory diet look like?

The Science Behind Anti-Inflammatory Diets

ScientistLet me start by saying that the science behind anti-inflammatory diets is nowhere near as strong as it is for the effect of primarily plant-based diets on heart disease and diabetes. The studies on anti-inflammatory diets are mostly small, short duration studies. However, the biggest problem is that there is no standard way of measuring inflammation.

There are multiple markers of inflammation, and they do not change together. That means that in every study some markers of inflammation are altered, while others are not. There is no consistent pattern from one study to another.

In spite of these methodological difficulties, the studies generally point in the same direction. Let’s start with the strongest evidence and work our way down to the weakest evidence. 

Omega-3 fats are anti-inflammatory (I. Reinders et al, European Journal of Clinical Nutrition, 66: 736-741, 2011). The evidence is strongest for the long chain omega-3s found in fish and fish oil, but the shorter chain omega-3s found in foods like walnuts, flaxseeds, chia seeds and flaxseed oil, soybean oil, and canola oil also appear to be anti-inflammatory. 

Inflammation is directly correlated with glycemic index (L. Qi and F.B. Lu, Current Opinion in Lipidology, 18: 3-8, 2007). This has a couple of important implications.

The most straightforward is that refined carbohydrates and sugars (sodas, pastries, and desserts), which have a high glycemic index, increase inflammation. In contrast, complex carbohydrates (whole grains, most fruits and vegetables) decrease inflammation. No surprise there. The second implication is that it is the glycemic index, not the sugar, that is driving the inflammatory response.

That means we need to look more closely at foods than at sugars. Sodas, pastries and desserts are likely to cause inflammation, but sugar-containing foods with a low glycemic index are unlikely to be inflammatory. 

Fruits and vegetables are anti-inflammatory. This has been shown in multiple studies. At this point most of the research is centered on identifying the nutrients and phytonutrients from fruits and vegetables that are responsible for the reduction in inflammation. I suspect the investigators are hoping to design an anti-inflammatory supplement and make lots of money. I will stick with the fresh fruits and vegetables. 

Saturated fats are inflammatory. At face value, the data on saturated fats appear to be contradictory. Some Fatty Foodsstudies say that saturated fats increase inflammation, while others say they do not. However, similar to my earlier discussion on saturated fats and heart disease), the outcome of the study depends on what the saturated fats are replaced with.

When saturated fats are replaced with refined carbohydrates, sugar and highly processed foods (the standard American low-fat diet), inflammation doesn’t change. This doesn’t mean that a diet high in saturated fat is healthy. It just means that both diets are bad for you. Both are inflammatory.

However, when saturated fat is replaced with omega-3 polyunsaturated fats (J.A. Paniagua et al, Atherosclerosis, 218: 443-450, 2011) or monounsaturated fats (B. Vessby et al, Diabetologia, 44: 312-319, 2001), markers of inflammation decrease. Clearly, saturated fats are not the best fat choice if you wish to keep inflammation in check.

I would be remiss if I did not address the claims by the low-carb diet proponents that saturated fats do not increase inflammation in the context of a low-carb diet. I want to remind you of two things we have discussed previously:

  • The comparisons in those studies are generally with people consuming a diet high in simple carbohydrates and sugars.
  • These studies have mostly been done in the short-term when the participants are losing weight on the low-carb diets. Weight loss decreases inflammation, so the reduction in inflammation on the low-carb diet could be coming from the weight loss.

The one study (M. Miller et al, Journal of the American Dietetic Association, 109: 713-717, 2009) I have found that compares a low-carb diet (the Atkins diet) with a good diet (the Ornish diet, which is a low-fat, lacto-ovo vegetarian diet) during weight maintenance found that the meat based, low-carb Atkins diet caused greater inflammation than the healthy low-fat Ornish diet.

Red meat is probably pro-inflammatory. Most, but not all, studies suggest that red meat consumption is associated with increased inflammation. If it is pro-inflammatory, the inflammation is most likely associated with its saturated fat, its heme iron content, or the advanced glycation end products formed during cooking.

What Is An Anti-Inflammatory Diet?

Colorful fruits and vegetablesAnti-inflammatory diets have become so mainstream that they now appear on many reputable health organization websites such as Harvard Health, WebMD, the Mayo Clinic, and the Cleveland Clinic. Each have slightly different features, but there is a tremendous amount of agreement. 

Foods an anti-inflammatory diet includes: In a nutshell, an anti-inflammatory diet includes fruits and vegetables, whole grains, plant-based proteins (like beans and nuts), fatty fish, and fresh herbs and spices. Specifically, your diet should emphasize:

  • Colorful fruits and vegetables. Not only do they help fight inflammation, but they are a great source of antioxidants and other nutrients important for your health.
  • Whole grains. They have a low glycemic index. They are also a good source of fiber, and fiber helps flush inflammatory toxins out of the body.
  • Beans and other legumes. They should be your primary source of protein. They are high in fiber and contain antioxidants and other anti-inflammatory nutrients.
  • Nuts, olive oil, and avocados. They are good sources of healthy monounsaturated fats, which fight inflammation.
  • Fatty fish. Salmon, tuna, and sardines are all great sources of long chain omega-3 fatty acids, which are fish and fish oilincorporated into our cell membranes. Those long chain omega-3s in cell membranes are, in turn, used to create compounds that are powerful inflammation fighters.

Walnuts, flaxseeds, and chia seeds are good sources of short chain omega-3s. The efficiency of their conversion to long chain omega-3s that can be incorporated into cell membranes is only around 2-5%. If they fight inflammation, it is probably because they replace some of the saturated fats and omega-6 fats you might otherwise be eating.

  • Herbs and spices. They add antioxidants and other phytonutrients that fight inflammation.

Foods an anti-inflammatory diet excludes: In a nutshell, an anti-inflammatory diet should exclude highly processed, overly greasy, or super sweet foods, especially sodas and other sweet drinks. Specifically, your diet should exclude:

  • Refined carbohydrates, sodas and sugary foods. They have a high glycemic index, which is associated with inflammation. They can also lead to weight gain and high blood sugar, both of which cause inflammation.
  • Foods high in saturated fats. This includes fatty and processed meats, butter, and high fat dairy products.
  • Foods high in trans fats. This includes margarine, coffee creamers, and any processed food containing partly hydrogenated vegetable oils. Trans fats are very pro-inflammatory.
  • French fries, fried chicken, and other fried foods. They used to be fried in saturated fat and/or trans fat. Nowadays, they are generally fried in omega-6 vegetable oils. A little omega-6 in the diet is OK, but Americans get too much omega-6 fatty acids in their diet. Most studies show that a high ratio of omega-6 to omega-3 fatty acids is pro-inflammatory.
  • Foods you are allergic or sensitive to. Eating any food that you are sensitive to can cause inflammation. This comes up most often with respect to gluten and dairy because so many people are sensitive to one or both. However, if you are not sensitive to them, there is no reason to exclude whole grain gluten-containing foods or low-fat dairy foods from your diet.

Can Diet Douse The Flames?

FlamesIn case you didn’t notice, the recommendations for an anti-inflammatory diet closely match the other healthy diets I have discussed previously. It should come as no surprise then that both the Mediterranean (L. Gallard, Nutrition in Clinical Practice, 25: 634-640, 2010; L. Schwingshackl and G. Hoffmann, Nutrition Metabolism and Cardiovascular Diseases, 24: 929-939, 2014) and DASH (D.E. King et al, Archives of Internal Medicine, 167: 502-506, 2007) diets are anti-inflammatory.

Vegan and vegetarian diets also appear to be anti-inflammatory as well. The anti-inflammatory nature of these diets undoubtedly contributes to their association with a lower risk of heart disease, diabetes, and cancer.

As for the low-carb diets, the jury is out. There are no long-term studies to support the claims of low-carb proponents that their diets reduce inflammation. The few long-term studies that are available suggest that low-carb diets are only likely to be anti-inflammatory if vegetable proteins and oils replace the animal proteins and fats that are currently recommended.

What does this mean for you if you have severe arthritis or other inflammatory diseases? An anti-inflammatory diet is unlikely to “cure” your symptoms by itself. However, it should definitely be a companion to everything else you are doing to reduce inflammation.

The Bottom Line 

If you have arthritis, colitis, bursitis, or any of the other “itis” diseases, you already know that inflammation is the enemy. Chronic, low level inflammation is also a contributing factor to heart disease, cancer, and many other diseases. Clearly, inflammation is a bad actor. It’s something we want to avoid.

Obesity and diabetes are two of the biggest contributors to inflammation, but does diet also play a role? With all the anti-inflammation diets circulating on the internet, you would certainly think so. In this article I review the evidence that certain foods influence inflammation and describe what an anti-inflammatory diet looks like.

For more details read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Which Diets Are Best In 2021?

Which Diet Should You Choose?

Emoticon-BadMany of you started 2021 with goals of losing weight and/or improving your health. In many cases, that involved choosing a new diet. That was only 2 months ago, but it probably feels like an eternity.

For many of you the “bloom” has gone off the new diet you started so enthusiastically in January.

  • Perhaps the diet isn’t working as well as advertised…
  • Perhaps the diet is too restrictive. You are finding it hard to stick with…
  • Perhaps you are always hungry or constantly fighting food cravings…
  • Perhaps you are starting to wonder whether there is a better diet than the one you chose in January…
  • Perhaps you are wondering whether the diet you chose is the wrong one for you…

If you are rethinking your diet, you might want to know which diets the experts recommend. Unfortunately, that’s not as easy as it sounds. The diet world has become just as divided as the political world.

Fortunately, you have an impartial resource. Each year US News & World Report invites a panel of experts with different points of view to evaluate popular diets. They then combine the input from all the experts into rankings of the diets in various categories.

If you are still searching for your ideal diet, I will summarize the US News & World Report’s “Best Diets In 2021”. For the full report, click on this link.

How Was This Report Created?

Expert PanelUS News & World Report recruited panel of 25 nationally recognized experts in diet, nutrition, obesity, food psychology, diabetes, and heart disease to review the 39 most popular diets.  They rated each diet in seven categories:

  • How easy it is to follow.
  • Its ability to produce short-term weight loss.
  • Its ability to produce long-term weight loss.
  • its nutritional completeness.
  • Its safety.
  • Its potential for preventing and managing diabetes.
  • Its potential for preventing and managing heart disease.

They converted the experts’ ratings to scores 5 (highest) to 1 (lowest). They then used these scores to construct nine sets of Best Diets rankings:

  • Best Diets Overall combines panelists’ ratings in all seven categories. However, all categories were not equally weighted. Short-term and long-term weight loss were combined, with long-term ratings getting twice the weight. Why? A diet’s true test is whether it can be sustained for years. And safety was double counted because no diet should be dangerous.
  • Best Commercial Diets uses the same approach to rank 15 structured diet programs that require a participation fee or promote the use of branded food or nutritional products.
  • Best Weight-Loss Diets was generated by combining short-term and long-term weight-loss ratings, weighting both equally. Some dieters want to drop pounds fast, while others, looking years ahead, are aiming for slow and steady. Equal weighting accepts both goals as worthy.
  • Best Diabetes Diets is based on averaged diabetes ratings.
  • Best Heart-Healthy Diets uses averaged heart-health ratings.
  • Best Diets for Healthy Eating combines nutritional completeness and safety ratings, giving twice the weight to safety. A healthy diet should provide sufficient calories and not fall seriously short on important nutrients or entire food groups.
  • Easiest Diets to Follow represents panelists’ averaged judgments about each diet’s taste appeal, ease of initial adjustment, ability to keep dieters from feeling hungry and imposition of special requirements.
  • Best Plant-Based Diets uses the same approach as Best Diets Overall to rank 12 plans that emphasize minimally processed foods from plants.
  • Best Fast Weight-Loss Diets is based on short-term weight-loss ratings.

Which Diets Are Best In 2021?

The word WInner in white letters surrounded by a burst of colorful stars in 3d

Are you ready? If this were an awards program I would be saying “Envelop please” and would open the envelop slowly to build suspense.

However, I am not going to do that. Here are the top 5 and bottom 5 diets in each category (If you would like to see where your favorite diet ranked, click on this link). [Note: I excluded commercial diets from this review.]

Best Diets Overall 

The Top 5: 

#1: Mediterranean Diet

#2: DASH Diet (This diet was designed to keep blood pressure under control, but you can also think of it as an Americanized version of the Mediterranean diet.)

#3: Flexitarian Diet (A flexible semi-vegetarian diet).

#4: Mayo Clinic Diet

#5: MIND Diet (This diet is a combination of Mediterranean and DASH but is specifically designed to reduce cognitive decline as we age.)

The Bottom 5: 

#35: Modified Keto Diet

#36: Whole 30 Diet

#37: GAPS Diet (A diet designed to improve gut health).

#38: Keto Diet

#39: Dukan Diet

Best Weight-Loss DietsWeight Loss

The Top 5: 

#1: Flexitarian Diet

#2: Vegan Diet

#3: Volumetrics Diet (A diet based on the caloric density of foods).

#4: Mayo Clinic Diet

#5: Ornish Diet

The Bottom 5: 

#35: Fertility Diet

#36: Whole 30 Diet

#37: Alkaline Diet

#38: AIP Diet (A diet designed for people with autoimmune diseases)

#39: GAPS Diet

Best Diabetes Diets

The Top 5: 

#1: Flexitarian Diet

#2: Mediterranean Diet

#3: DASH Diet

#4: Mayo Clinic Diet

#5: Vegan Diet

The Bottom 5: 

#35: The Fast Diet

#36: AIP Diet

#37: GAPS Diet

#38: Whole 30 Diet (A diet designed for people with autoimmune diseases)

#39: Dukan Diet

strong heartBest Heart-Healthy Diets 

The Top 5: 

#1: DASH Diet

#2: Mediterranean Diet

#3: Ornish Diet (A diet based on the caloric density of foods).

#4: Flexitarian Diet

#5: Vegan Diet

The Bottom 5: 

#35: Keto Diet

#36: AIP Diet

#37: Whole 30 Diet

#38: Modified Keto Diet

#39: GAPS Diet

Best Diets for Healthy Eating

The Top 5: 

#1: DASH Diet

#2: Mediterranean Diet

#3: Flexitarian Diet

#4: TLC Diet (A diet designed to promote heart health)

#5: MIND Diet

The Bottom 5: 

#35: Atkins Diet

#36: Raw Food Diet

#37: Modified Keto Diet

#38: Dukan Diet

#39: Keto Diet 

Easiest Diets to FollowEasy

The Top 5: 

#1: Mediterranean Diet

#2: Flexitarian Diet

#3: MIND Diet

#4: DASH Diet

#5: Fertility Diet

The Bottom 5: 

#35: Keto Diet and Modified Keto Diet (tie)

#36: Whole 30 Diet

#37: Dukan Diet

#38: GAPS Diet

#39: Raw Foods Diet 

Best Fast Weight-Loss Diets

The Top 5 (Excluding Commercial Diets): 

#1: Atkins Diet

#2: Biggest Loser Diet

#3: Keto Diet

#4: Raw Food Diet

#5: Volumetrics Diet

Which Diets Are Best For Rapid Weight Loss?

Happy woman on scaleLet me start with some general principles:

#1: If you are looking for rapid weight loss, any whole food restrictive diet will do.

  • The Atkins and keto diets are meat heavy, low carb diets. They restrict fruits, some vegetables, grains, and most legumes.
  • The Biggest Loser diet relies on restrictive meal plan and exercise programs.
  • The restrictions of the raw food diet are obvious.
  • The volumetrics diet restricts foods with high caloric density.
  • The vegan diet, which ranks #7 on this list, is a very low fat diet that eliminates meat, dairy, eggs, and animal fats.
  • I did not include commercial diets that rated high on this list, but they are all restrictive in one way or another.

#2: Restrictive diets ultimately fail.

  • The truth is 90-95% of people who lose weight quickly on a restrictive diet regain most of that weight in the next two years. The pounds come back and often bring their friends along as well. Many people regain more weight than they lost. This is the famous “Yo-Yo Effect”.
  • If dieters paid for one of the commercial diets, they may as well have burned their money.
  • When I talk with people about weight loss, many of them tell me the Atkins diet is the only one they can lose weight on. That would be impressive if they were at a healthy weight, but most are not. They are overweight. I am starting to see the same thing from overweight people who have used the keto diet to lose weight and have regained their weight.

#3: We should ask what happens when we get tired of restrictive diets and add back some of your favorite foods.

  • If you lose weight on a vegan diet and add back some of your favorite foods, you might end up with a semi-vegetarian diet. This is a healthy diet that can help you maintain your weight loss.
  • If you lose weight on the Atkins or keto diets and add back some of your favorite foods, you end up with the typical American diet – one that is high in both fat and carbs. This is not a recipe for long-term success.
  • Long term weight loss is possible if you transition to a healthy diet after you have lost the weight. In a recent article in “Health Tips From The Professor” I wrote about an organization called the National Weight Control Registry. These are people who have been successful at keeping the weight off. For purposes of this discussion, two points are important.
  • They lost weight on every possible diet.
  • They kept the weight off by following a healthy reduced calorie, low fat diet. (For what else they did, click here).

Which Diet Should You Choose?

Which Diet Is BestWith rapid weight loss out of the way, let’s get back to the question, “Which Diet Should You Choose?” My recommendations are:

  • Choose a diet that fits your needs. That is one of the things I like best about the US News & World Report ratings. The diets are categorized. If your main concern is diabetes, choose one of the top diets in that category. If your main concern is heart health… You get the point.
  • Choose diets that are healthy and associated with long term weight loss. If that is your goal, you will notice that primarily plant-based diets top these lists. Meat-based, low carb diets like Atkins and keto are near the bottom of the lists.
  • Choose diets that are easy to follow. The less-restrictive primarily plant-based diets top this list – diets like Mediterranean, DASH, MIND, and flexitarian.
  • Choose diets that fit your lifestyle and dietary preferences. For example, if you don’t like fish and olive oil, you will probably do much better with the DASH or flexitarian diet than with the Mediterranean diet.
  • Finally, focus on what you have to gain, rather than on foods you have to give up.
    • On the minus side, none of the diets include sodas, junk foods, and highly processed foods. Teose foods should go on your “No-No” list. Sweets should be occasional treats and only as part of a healthy meal. Meat, especially red meat, should become a garnish rather than a main course.
    • On the plus side, primarily plant-based diets offer a cornucopia of delicious plant foods you probably didn’t even know existed. Plus, for any of the top-rated plant-based diets, there are websites and books full of mouth-watering recipes. Be adventurous.

The Bottom Line 

For many of you the “bloom” has gone off the new diet you started so enthusiastically in January. If you are rethinking your diet, you might want to know which diets the experts recommend. Unfortunately, that’s not as easy as it sounds. The diet world has become just as divided as the political world.

Fortunately, you have an impartial resource. Each year US News & World Report invites a panel of experts with different points of view to evaluate popular diets. They then combine the input from all the experts into rankings of the diets in various categories. In the article above I summarize the US News & World Report’s “Best Diets In 2021”.

There are probably two questions at the top of your list.

#1: Which diets are best for rapid weight loss? Here are some general principles:

  • If you are looking for rapid weight loss, any whole food restrictive diet will do.
  • Restrictive diets ultimately fail.
  • We should ask what happens when we get tired of restrictive diets and add back some of our favorite foods.
  • Long term weight loss is possible if you transition to a healthy diet after you have lost the weight.

#2: Which diet should you choose? Here the principles are:

  • Choose a diet that fits your needs.
  • Choose diets that are healthy and associated with long term weight loss.
  • Choose diets that are easy to follow.
  • Choose diets that fit your lifestyle and dietary preferences.
  • Finally, focus on what you have to gain, rather than on foods you have to give up.

For more details on the diet that is best for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Which Weight Loss Diet Is Best For You?

Tips For Choosing A Diet That Works

Author: Dr. Stephen Chaney

New Year DietDiet season starts in just a few days! Like millions of Americans you will probably be setting a goal to lose weight. But which diet should you choose? Vegan, Paleo, Keto, 360, Intermittent Fasting, low-carb, low fat – the list is endless.

And then there are the commercial diets: Meal replacements, low calorie processed foods, prepared meals delivered to your door – just to name a few of the categories.

You can choose to count calories, focus on portion sizes, or keep a food journal.

And, if you really want to live dangerously, you can try the latest diet pills that claim to curb your appetite and rev up your metabolism.

The advertisements for all these diets sound so convincing. They give you scientific-sounding mumbo-jumbo to explain why they work. Then they talk about clinical studies they say prove their diet works.

If you are like most Americans, you have already tried several of these diets. They worked for a while, but the pounds came back – and brought their friends with them.

But, as the saying goes, “Hope springs eternal in the human breast. Surely some diet you haven’t tried yet will work for you.

There is such a diet. But it will require a change of mindset. It will also require effort. There is no magic wand that will chase the extra pounds away forever.

If you are searching for the perfect diet to start the new year, let me be your guide. Here are:

  • 4 tips on what to avoid and…
  • 6 tips on what to look for…

…when you are choosing the perfect diet.

Tips For Choosing A Diet That Works

Things To Avoid:

Avoid1) Endorsements

Endorsements by your favorite athlete or public person are paid for. They don’t necessarily represent their opinion. Nor do they assure you that they follow that diet or use that diet supplement.

Endorsements by Dr. Strangelove and his buddies can be equally misleading. They usually tell you that the medical establishment has been lying to you, and they have discovered the “secret” to permanent weight loss and the “Fountain of Youth”.

Recommendations of the medical and scientific communities usually represent a consensus statement by the top experts in their field. I would choose their advice over Dr. Strangelove’s opinion any day.

2) Testimonials

Most of the testimonials you see on TV or in print are either paid for or are fake

Testimonials by your friends can be equally misleading. We are all different. What works for your friend or your trainer may not work for you.

For example, some of us do better on low-carb diets, and others do better on low fat diets.

[Note: Some DNA testing companies claim they can sequence your DNA and tell you which diet is best. However, as I reported in a recent article in “Health Tips From The Professor”, independent studies show that DNA testing is of no use in predicting whether low-carb or low-fat diets are better for you.]

3) Diets Based on “Magic” Or “Forbidden” Foods or Food Groups.

I have often said we have 5 food groups for a reason. Each food group provides a unique blend of nutrients and phytonutrients. And each plant food group provides a unique blend of fibers that support the growth of different types of friendly gut bacteria.

The bottom line is that each of us does better with some foods than others, but there are no “magic” or “forbidden” foods that apply to everyone.

4) “Magic” Diets.

Magic WandI have written perhaps the first diet book, “Slaying The Food Myths”, that doesn’t feature a “magic” diet that is going to make the pounds melt away and allow you to live to 100. Instead I recommend a variety of healthy diets and suggest you choose the one that fits you best.

However, I understand the allure of “magic” diets. Dr. Strangelove claims the diet will be effortless. He gives you some scientific-sounding mumbo-jumbo to convince you the diet is scientifically sound. Then he cites some clinical studies showing the diet will cause you to lose weight and will improve your health parameters (things like cholesterol, triglycerides, blood sugar, and blood pressure). It sounds so convincing.

Before you fall for Dr. Strangelove’s latest “magic” diet, let me share two things that may blow your mind:

    • The studies are all short-term (usually 3 months or less).
    • When you rely on short-term studies, the very low-fat Vegan diet and very low-carb Keto diet give you virtually identical weight loss and improvement in health parameters!

Those two diets are as different as any two diets could be. That means we can forget all the scientific-sounding mumbo-jumbo as to why each of those diets work. Instead, we should ask what these two diets have in common.

The answer is simple:

#1: The clinical studies are comparing “magic” diets to the typical American diet. Anything is better than the typical American diet! It is high in sugar, refined carbohydrates, saturated fat, and highly processed foods. No wonder the “magic” diets look so good.

#2: The diets are whole food diets. Anytime you eliminate sodas, fast foods, and highly processed foods, you will lose weight.

#3: The diets eliminate one or more food groups. Whenever you eliminate some of your favorite foods from your diet, you tend to lose weight without thinking about it. I call this the cream cheese and bagels phenomenon.

  • If you are following a low-fat diet, it sounds great to say you can eat all the bagels you want. But without cream cheese to go with the bagels, you tend to eat fewer bagels.
  • If you are following a low-carb diet, it sounds great to say you can eat as much cream cheese as you want, but without bagels to go with your cream cheese, you tend to eat less cream cheese.

#4: Because they eliminate many of your favorite foods, “magic” diets make you focus on what you eat. Whenever you focus on what you eat, you tend to lose weight. That is why food journals and calorie counters are effective.

#5: Finally, whenever you lose weight, your health parameters (cholesterol, triglycerides, blood sugar, and blood pressure) improve.

Things To Look For In Choosing A Healthy Diet For The New Year

Look For1) Choose whole food diets. Avoid sodas, fast foods, and highly processed foods.

2) Choose primarily plant-based diets. These can range from Vegan through semi-vegetarian, Mediterranean, DASH, and Nordic. All are healthy diets. I have discussed the evidence for this recommendation in my book “Slaying The Food Myths”. Here is a brief summary.

When we look at long term (10-20 year) studies:

    • Vegetarians weigh less and are healthier than people consuming the typical American diet.
    • People consuming semi-vegetarian, Mediterranean, and DASH diets are healthier than people consuming the typical American diet.

If you look at low-carb diets:

    • People consuming plant-based low-carb diets weigh less and are healthier than people consuming the typical American diet.
    • People consuming meat-based low-carb diets are just as fat and unhealthy as people consuming the typical American diet.
    • The Atkins diet low-carb diet has been around for more than 50 years, and there is no evidence it is healthy long-term

3) Choose diets that include a variety of foods from all 5 food groups. I have discussed the rationale for that recommendation above.

4) Choose diets that consider meat as a garnish, not a main course.

5) Choose diets that feature healthy carbs and healthy fats rather than low-carb or low-fat diets.

6) Think lifestyle, not diet. If you choose a restrictive diet so you can achieve quick weight loss, you will probably be just as fat and unhealthy next December 31st as you are this year. Instead, choose diets that teach healthy eating and lifestyle changes that you can make a permanent part of your life.

Tips For Keeping The Weight Off

Yo-Yo You know the brutal truth. Around 95% of dieters regain everything they lost and then some within a few years. You have probably gone through one or more cycles of weight loss and regain yourself – something called “yo-yo dieting”. You may even be asking yourself if it is worth bothering to try to lose weight this year.

Rather focusing on the negative statistics of weight loss, let’s look at the good news. There are people who lose the weight and keep it off. What do they do?

There is an organization called the National Weight Control Registry that has enrolled more than 10,000 people who have lost weight and kept it off. The people in this group lost weight on almost every diet imaginable. However, here is the important statistic: On average people in this group have lost 66 pounds and kept it off for 5 years.

The National Weight Control Registry has kept track of what they have done to keep the weight off. Here is what they do that you may not be doing:

  • They consume a reduced calorie, low fat diet.
  • They get lots of exercise (around 1 hour/day).
  • They have internalized their eating patterns. In short, this is no longer a diet. It has become a permanent part of their lifestyle. This is the way they eat without even thinking about it.
  • They monitor their weight regularly. When they gain a few pounds, they modify their diet until they are back at their target weight.
  • They eat breakfast on a regular basis.
  • They watch less than 10 hours of TV/week.
  • They are consistent (no planned cheat days).

Which Weight Loss Diet Is Best For You?

I have covered a lot of ground in this article. Let me summarize it for you.

If you are thinking about popular diets:

  • Primarily plant-based diets ranging from Vegan to Mediterranean and Dash are associated with a healthier weight and better health long term.
  • If want to lose weight quickly, you may want to start with the more restrictive plant-based diets, like Vegan, Ornish, Pritikin or semi-vegetarian.
  • If you do better with a low-carb diet, my recommendation is the low-carb version of the Mediterranean diet.
  • If your primary goal is rapid weight loss, you could also start with one of the healthier of the restrictive low-carb diets, like the Paleo or the 360 diet. I do not recommend the Keto diet.
  • No matter what diet you start with, plan to transition to the primarily plant-based diet that best fits your lifestyle and food preferences. This is the diet you will want to stick with to maintain your weight loss and achieve better health long term.
  • Plan on permanent lifestyle change rather than a short-term diet. Otherwise, you are just wasting your time.
  • Eat whole foods. Big Food keeps up with America’s favorite diets and is only too happy to sell you highly processed foods that match your favorite diet. Avoid those like the plague.

If you are thinking about commercial diets featuring meal replacement products:

  • Look for meal replacement products that:
    • Do not contain artificial sweeteners, flavors, or preservatives.
    • Use non-GMO protein. A non-GMO certification for the other ingredients is not necessary. For a more detailed explanation of when non-GMO certification is important and when it is unnecessary, see my article in “Health Tips From the Professor”.
    • Have stringent quality controls in place to assure purity. “Organic” and/or “non-GMO” on the label do not assure purity.
  • Look for programs that can provide clinical studies showing their diet plan is effective for weight loss and for keeping the weight off. Many programs have short-term clinical studies showing they are effective for weight loss, but very few have longer-term studies showing the weight stays off.
  • Finally, look for programs that teach permanent lifestyle change. This should include guidance on exercise and healthy eating.

I do not recommend most commercial diets that feature prepared low-calorie foods “shipped right to your door” as a major part of their program. The foods are highly processed. Plus, they include all your favorite unhealthy foods as part of the program. Even if they include lifestyle change as part of their program, they are undermining their message with the foods they are providing you.

I would be remiss if I didn’t mention that Weight Watchers is highly recommended by most experts in the field. Weight Watchers emphasizes journaling and counting calories, which is a plus because it makes you focus on what you are eating. They also have a good lifestyle program and support that can help you transition to permanent lifestyle change if you are willing to put in the effort. However, I don’t recommend their prepared low-calorie foods. They are no better than foods provided by the other commercial diet programs.

The Bottom Line 

Weight loss season is upon us. If you plan to lose weight and/or adopt a healthier diet in the coming year, you are probably trying to decide which diet to try this year. In this issue of “Health Tips From The Professor” I give you:

  • 4 tips on what to avoid when selecting your diet.
  • 6 tips on how to choose your perfect diet.
  • 7 tips on how to keep the weight off.

Then I put all this information together to help you choose the best diet, the best meal replacement product, and/or the best commercial diet program.

For more details read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Does Maternal Vitamin D Affect Childhood ADHD?

Can ADHD Be Prevented?

vitamin dIf you are pregnant, or of childbearing age, should you be supplementing with vitamin D? Increasingly, the answer appears to be yes.

1) Based on blood 25-hydroxy vitamin D levels (considered the most accurate marker of vitamin D status):

    • 8-11% of pregnant women in the US are deficient in vitamin D (<30 nmol/L).
    • 25% of pregnant women have insufficient vitamin D status (30-49 nmol/L).

In short, that means around 1/3 of pregnant women in the US have insufficient or deficient levels of vitamin D. The effect of inadequate vitamin D during pregnancy is not just an academic question.

2) The Cochrane Collaboration (considered the gold standard for evidence-based medicine) has recently concluded that supplementation with vitamin D reduces the risk of significant complications during pregnancy.

3) Another recent study found that inadequate vitamin D status during pregnancy delayed several neurodevelopmental milestones in early childhood, including gross motor skills, fine motor skills, and social development.

If neurodevelopmental milestones are affected, what about ADHD? Here the evidence is not as clear. Some studies have concluded that vitamin D deficiency during pregnancy increases the risk of ADHD in the offspring. Other studies have concluded there is no effect of vitamin D deficiency on ADHD.

Why the discrepancy between studies?

  • Most of the previous studies have been small. Simply put, there were too few children in the study to make statistically reliable conclusions.
  • Most of the studies measured maternal 25-hydroxyvitamin D levels in the third trimester or in chord blood at birth. However, it is during early pregnancy that critical steps in the development of the nervous system take place.

Thus, there is a critical need for larger studies that measure maternal vitamin D status in the first trimester of pregnancy. This study (M Sucksdorff et al, Journal of the American Academy of Child & Adolescent Psychiatry, 2020, in press) was designed to fill that need.

How Was The Study Done?

Clinical StudyThis study compared 1,067 Finnish children born between 1998 and 1999 who were subsequently diagnosed with ADHD and 1,067 matched controls without ADHD. There were several reasons for choosing this experimental group.

  • Finland is among the northernmost European countries, so sun exposure during the winter is significantly less than for the United States and most other European countries. This time period also preceded the universal supplementation with vitamin D for pregnant women that was instituted in 2004.

Consequently, maternal 25-hydroxyvitamin D levels were significantly lower than in most other countries. This means that a significant percentage of pregnant women were deficient in vitamin D, something not seen in most other studies. For example:

    • 49% of pregnant women in Finland were deficient in vitamin D (25-hydoxyvitamin D <30 nmol/L) compared to 8-11% in the United States.
    • 33% of pregnant women in Finland had insufficient vitamin D status (25-hydroxyvitamin D 30-49.9 nmol/L) compared to 25% in the United States.
  • Finland, like many European countries, keeps detailed health records on its citizens. For example:
    • The Finnish Prenatal Study collected data, including maternal 25-hydroxyvitamin D levels during the first trimester), for all live births between 1991 and 2005.
    • The Care Register for Health Care recorded, among other things, all diagnoses of ADHD through 2011.

Thus, this study was ideally positioned to compare maternal 25-hydroxyvitamin D levels during the first trimester of pregnancy with a subsequent diagnosis of ADHD in the offspring. The long-term follow-up was important to this study because the average age of ADHD diagnosis was 7 years (range = 2-14 years).

Does Maternal Vitamin D Affect Childhood ADHD?

Child With ADHDThe answer to this question appears to be a clear, yes.

If you divide maternal vitamin D levels into quintiles:

  • Offspring of mothers in the lowest vitamin D quintile (25-hydroxyvitamin D of 7.5-21.9 nmol/L) were 53% more likely to develop ADHD than offspring of mothers in the highest vitamin D quintile (49.5-132.5 nmol/L).

When you divide maternal vitamin D levels by the standard designations of deficient (<30 nmol/L), insufficient (30-49.9 nmol/L), and sufficient (≥50 nmol/L):

  • Offspring of mothers who were deficient in vitamin D were 34% more likely to develop ADHD than children of mothers with sufficient vitamin D status.

The authors concluded: “This is the first population-based study to demonstrate an association between low maternal vitamin D during the first trimester of pregnancy and an elevated risk for ADHD diagnosis in offspring. If these findings are replicated, they may have public health implications for vitamin D supplementation and perhaps changing lifestyle behaviors during pregnancy to ensure optimal maternal vitamin D levels.”

Can ADHD Be Prevented?

Child Raising HandI realize that this is an emotionally charged title. If you have a child with ADHD, the last thing I want is for you to feel guilty about something you may not have done. So, let me start by acknowledging that there are genetic and environmental risk factors for ADHD that you cannot control. That means you could have done everything right during pregnancy and still have a child who develops ADHD.

Having said that, let’s examine things that can be done to reduce the risk of giving birth to a child who will develop ADHD, starting with vitamin D. There are two aspects of this study that are important to keep in mind.

#1: The increased risk of giving birth to a child who develops ADHD was only seen for women who were vitamin D deficient. While vitamin D deficiency is only found in 8-11% of pregnant mothers in the United States, that is an average number. It is more useful to ask who is most likely to be vitamin D deficient in this country. For example:

  • Fatty fish and vitamin D-fortified dairy products are the most important food sources of vitamin D. Fatty fish are not everyone’s favorite and may be too expensive for those on a tight budget. Many people are lactose intolerant or avoid milk for other reasons. If you are not eating these foods, you may not be getting enough vitamin D from your diet. This is particularly true for vegans.
  • If you have darker colored skin, you may have trouble making enough vitamin D from sunlight. If you are also lactose intolerant, you are in double trouble with respect to vitamin D sufficiency.
  • Obesity affects the distribution of vitamin D in the body. So, if you are overweight, you may have low 25-hydroxyvitamin D levels in your blood.
  • The vitamin D RDA for pregnant and lactating women is 600 IU, but many multivitamin and prenatal supplements only provide 400 IU. If you are pregnant or of childbearing age, it is a good idea to look for a multivitamin or prenatal supplement that provides at least 600 IU, especially if you are in one of the high risk groups listed above.
  • Some experts recommend 2,000 to 4,000 IU of supplemental vitamin D. I would not recommend exceeding that amount without discussing it with your health care provider first.
  • Finally, for reasons we do not understand, some people have a difficult time converting vitamin D to the active 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D in their bodies. If you are pregnant or of childbearing age, it is a good idea to have your blood 25-hydroxyvitamin D levels determined and discuss with your health care provider how much vitamin D you should be taking. Many people need more than 600 IU to reach vitamin D sufficiency status.

#2: Maternal vitamin D deficiency has a relatively small effect (34%) on the risk of the offspring developing ADHD. That means assuring adequate vitamin D status during pregnancy should be part of a holistic approach for reducing ADHD risk. Other factors to consider are:

  • Low maternal folate and omega-3 status.
  • Smoking, drug, and alcohol use.
  • Obesity.
  • Sodas and highly processed foods.

Alone, each of these factors has a small and uncertain influence on the risk of your child developing ADHD. Together, they may play a significant role in determining your child’s risk of developing ADHD.

In closing, there are three take-home lessons I want to leave you with:

1) The first is that there is no “magic bullet”. There is no single action you can take during pregnancy that will dramatically reduce your risk of giving birth to a child who will develop ADHD. Improving your vitamin D, folate, and omega-3 status; avoiding cigarettes, drugs, and alcohol; achieving a healthy weight; and eating a healthy diet are all part of a holistic approach for reducing the risk of your child developing ADHD.

2) The second is that we should not think of these actions solely in terms of reducing ADHD risk. Each of these actions will lead to a healthier pregnancy and a healthier child in many other ways.

3) Finally, if you have a child with ADHD and would like to reduce the symptoms without drugs, I recommend this article.

The Bottom Line

A recent study looked at the correlation between maternal vitamin D status during the first trimester of pregnancy and the risk of ADHD in the offspring. The study found:

  • Offspring of mothers who were deficient in vitamin D were 34% more likely to develop ADHD than children of mothers with sufficient vitamin D status.

The authors concluded: “This is the first population-based study to demonstrate an association between low maternal vitamin D during the first trimester of pregnancy and an elevated risk for ADHD diagnosis in offspring. If these findings are replicated, they may have public health implications for vitamin D supplementation and perhaps changing lifestyle behaviors during pregnancy to ensure optimal maternal vitamin D levels.”

In the article above I discuss what this study means for you and other factors that increase the risk of giving birth to a child who will develop ADHD.

For more details read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

 

Preparing For The New Normal

Can Supplements Strengthen My Immune System?

COVID-19The United States and the rest of the world are facing the biggest challenge of our lifetimes. COVID-19 has killed hundreds of thousands of people and decimated economies around the world.

As of the publication date of this article we have no vaccine and only one treatment option that appears to be about 30% effective in a preliminary clinical trial. People are scared.

The question I get asked most often is: “Can supplements protect me from COVID-19”. That’s not a question I can answer with confidence. The few studies we have are small and preliminary. Plus, there is too much we still do not know about COVID-19.

However, there are studies about how diet and supplements affect the immune system. I can answer the question, “Can Supplements Strengthen My Immune System”, with confidence. That will be the focus of this article.

However, before covering that, let me take an objective look at what our “New Normal” will be like and how we can prepare for it.

Preparing For The New Normal

ProfessorAs a scientist I am appalled by the divisive and hyper-partisan arguments about how we should be handling the COVID-19 pandemic. This is a time when our country should be united against a common enemy. Instead I see myths and lies propagated on both sides of this important issue.

The press only magnifies the problem by repeating the myths without fact checking. Whether they are on the left or the right, the media only repeats myths that fit their narrative. As a result, people like you are confused and scared.

Let me try to give you a more objective and scientific view of what the “New Normal” will look like, and how we can prepare for it.

Let’s start with one of the biggest arguments over the past few weeks – when should we reopen our country. This argument is based on the myth that if we wait long enough, the virus will be gone, and life can return to normal.

Nothing could be further from the truth. In reality viruses don’t work that way. They continue to circulate through the population at low levels. Whenever we emerge from our homes and resume our daily lives, the virus will be lurking. There will be flare-ups. There will be hot spots. There will be deaths. And the press will report every one.

So, the question should not be when we emerge. It should be how we emerge. We should emerge cautiously. We should continue to take appropriate precautions. These precautions will become our “New Normal” until we have an effective vaccine. By now, you probably have the CDC precautions memorized, but let me repeat them here:

  • If you are sick, stay home until you recover. If your symptoms worsen, contact your doctor right away.
  • If you are exposed, get tested right away and self-quarantine for 14 days if you test positive.
  • When you go out, wear a face mask and practice social distancing. When you get home, wash your hands in soap and water for 20”.
  • For now, we will need to avoid the customary handshake (and if you are from the South like me, the customary hug).
  • If you are very old or very sick, you should stay home as much as possible. If you have a loved one in this category, you should do everything in your power to protect them from exposure.
  • The guideline that is hardest to project into the future is the one on crowd size. It is hard to predict what the CDC will recommend about crowd size as part of our “New Normal” a few months from now. However, because this virus is extremely contagious, it may be risky to attend any gatherings where there are large, tightly packed crowds for the foreseeable future. This could include some of our favorite things – like movies, live theater, night clubs, and sporting events.Myth Versus Facts

Finally, there is another big myth, namely that the virus will simply disappear once we have a vaccine. Vaccines reduce your risk of exposure because fewer people are carriers of the virus. However, coronaviruses never disappear. They continue to circulate in the population for decades.

Even after we have a vaccine, people will still get sick from COVID-19. People will still die from COVID-19. The difference is that we will no longer hear about COVID-19 cases and deaths on the nightly news. Those cases and deaths will just become part of the statistics that the CDC collects on flu-like illnesses each year – and everyone ignores.

Now that I have discussed what the “New Normal” will look like and summarized the CDC guidelines for reducing your exposure to COVID-19 as the lockdown eases, let me add another guideline of my own:

  • Keep your immune system as strong as possible.

Why Is Keeping Your Immune System Strong Important?

strong immune systemIt is no secret that the media likes to focus on bad news. It is the bad news that draws people in and keeps them coming back for more.

Pandemics are no different. It doesn’t matter whether we are talking about the Spanish flu, SARS, MERS, or COVID-19. We focus on cases and deaths – the bad news. We ignore the good news – there are millions of people who were infected and had no symptoms.

However, if you have been listening closely to what the experts have been saying rather than relying on the media for your information, the good news is obvious.

  • 80-85% of people who have tested positive for COVID-19 have mild or moderate symptoms. Their symptoms are no worse than they experience with the seasonal flu.
  • Preliminary antibody tests suggest that the number of people infected with COVID-19 who experience no symptoms may be 10 to 40 times higher than reported cases.
  • The experts say that the difference is a strong immune system. They tell us that it is people with weakened immune systems that suffer and die from COVID-19.

So, how do you keep your immune system strong? Let’s start by looking at the role of supplementation.

Can Supplements Strengthen My Immune System?

MultivitaminsThose of you who follow me know that I consider supplementation as just one aspect of a holistic approach to health. However, I am starting with supplements because the question I am often asked these days is: “Can supplements protect me from COVID-19”.

As I said at the beginning of this article, that is not a question I can answer with confidence. Instead, the question you should be asking is, “Can Supplements Strengthen My Immune System?”

As I mentioned above, the experts are telling us that it is people with weakened immune systems who suffer and die from COVID-19. That means it is important to keep our immune system as strong as possible.

How do we do that? Here is what an international group of experts said in a recent review (PC Calder et al, Nutrients, 12, 1181-1200, 2020).

1) “A wealth of mechanistic and clinical data show that vitamins A, B6, B12, C, D, E, and folate; trace elements zinc, iron, selenium, magnesium, and copper; and omega-3 fatty acids EPA and DHA play important and complementary roles in supporting the immune system.”

2) “Inadequate intake and status of these nutrients are widespread, leading to a decrease in resistance to infections, and an increase in disease burden.”

They then made the following recommendations:

1) Supplementation with the above micronutrients and omega-3 fatty acids is a safe, effective, and low-cost strategy to help support optimal immune function.

    • They recommended 100% of the RDA for vitamins A, B6, B12, C, D, E, and folate and minerals zinc, iron, selenium, magnesium, and copper in addition to the consumption of a well-balanced diet.
    • They recommended 250 mg/day of EPA + DHA.

2) Supplementation above the RDA for vitamins C and D is warranted.

    • They recommend 200 mg/day of vitamin C for healthy individuals and 1-2 g/day for individuals who are sick.
    • They recommend 2000 IU/day (50 ug/day) for vitamin D.

3) Public health officials are encouraged to include nutritional strategies in their recommendations to improve public health.

Their recommendations could be met by a multivitamin that provides all the micronutrients they recommend, an omega-3 supplement, and extra vitamins C and D.

What Else Should I Do To Strengthen My Immune System?

healthy foodsAs I said above, supplementation is only one part of a holistic approach to a strong immune system. Here are the other components of a holistic approach:

1) It starts with a healthy diet.

    • Eat foods from all 5 food groups.
    • Eat plenty of fruits and vegetables. They provide antioxidants and phytonutrients that are important for our immune system.
    • Eat plenty of high fiber foods. Include whole grains and beans in addition to fruits and vegetables. That’s because the friendly gut bacteria that strengthen our immune system need a variety of fibers from different food sources to feed on.
    • Eat oily fish on a regular basis.
    • Avoid sodas, sugary foods, and highly processed foods.
    • Avoid high fat diets

2) Get adequate sleep. For most of us, that means 7-8 hours of sleep a night.

3) Maintain a healthy weight.

4) Get adequate exercise. Aim for a minimum of 150 minutes of moderate intensity exercise each week.

5) Manage stress and anxiety in healthy ways. Yes, that means if you let the news about COVID-19 cause anxiety, you are weakening your immune system. You may want to turn off the news and try prayer, meditation, yoga, or whatever relieves stress for you.

The Bottom Line

In this article, I summarized the “New Normal” we face as we emerge from lockdown and how to navigate the new normal as safely as possible. If I were to summarize this article in a few short sentences, this is what I would say:

Until we have an effective vaccine the “New Normal” is a world in which a dangerous virus is lurking in the community, waiting to strike the unprepared.

Forget all the angry rhetoric about when we should emerge from lockdown. The important question is not when we emerge. It is how we emerge.

We don’t need to stay huddled in our homes, fearful to leave, unless we are very old or very sick.

We do need to take appropriate precautions when we leave home based on the recommendations of the CDC. None of us are invincible as far as this virus is concerned. More importantly, if we bring the virus home, we may kill the very people we love the most. We need to follow the guidelines.

We should also make sure that our immune system is as strong as possible through a holistic combination of diet, supplementation, adequate sleep, exercise, weight management, and stress reduction.

For more information on CDC COVID-19 Guidelines, click here.

For more details about preparing for the new normal and diet & supplementation recommendations, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

Does Diet Affect Sperm Quality?

Do Real Men Eat Meat?

Enjoying Red MeatMeat has a certain mystique among some men. They believe real men eat meat, especially red meat. The belief is that eating red meat makes them bigger, stronger, and more virile. In that world view, vegetarianism is effeminate.

How much of that is true? Let’s start by looking at the bigger and stronger part:

  • Animal proteins are higher in the branched chain amino acids, especially leucine, which help drive the increase in muscle mass associated with exercise. However, meat protein is digested slowly.
  • Milk protein is also high in branched chain amino acids and is digested more quickly. That’s why many body building supplements are whey protein based.
  • In addition, leucine is now being added to some of the plant protein supplements. Those supplements are often as effective as whey protein supplements at driving the increase in muscle mass associated with exercise

But what about virility? Does meat make men more virile? Fortunately, we now have an answer to these questions. A recent study (L Nassan et al., JAMA Network Open, 2020; 3(2) :e1921610) has looked at the effect of diet on sperm count and sperm quality.

How Was The Study Done?

Clinical StudyIn Denmark, all men are required to undergo a physical examination around age 18 to determine their fitness for military service. Research staff at the University Department of Growth and Reproduction at Rigshospitalet in Copenhagen approached young men undergoing their physical exams and invited them to participate in this study.

The men filled in a food frequency questionnaire, answered questions about their lifestyle and medical history and provided semen and blood samples for the study prior to undergoing their physical exam. 2935 men who were unaware of their fertility status and not using anabolic steroids were included in the data analysis.

The average age of participants in the study was 19 and 78% of them were of normal body weight.

The participants were divided into four groups based on their diet:

1.     Western Diet characterized by a higher intake of pizza, French fries, processed and red meats, snacks, refined grains, sugary beverages and sweets.

2.     Danish Diet characterized by a higher intake of cold processed meats, whole grains, fruits, mayonnaise, cold fish, condiments, and dairy.

3.     Vegetarian Diet characterized by a higher intake of vegetables, soymilk, and eggs, without red meat or chicken.

4.     Prudent (Healthy) Diet characterized by a higher intake of fish, chicken, vegetables, fruit, nuts, and water.

The effect of these diets on sperm count and sperm quality were compared.

Does Diet Affect Sperm Quality?

SpermWhen the authors measured sperm counts in the study participants, the results were as follows:

  • Greatest adherence to a prudent diet resulted in a sperm count of 167 million.
  • Greatest adherence to a vegetarian diet resulted in a sperm count of 151 million.
  • Greatest adherence to a Danish diet resulted in a sperm count of 146 million.
  • Greatest adherence to a Western diet resulted in a sperm count of only 122 million -27% lower than for men eating a prudent diet.
  • Similar results were reported for measure of sperm quality, such as sperm motility (how fast the sperm can swim) and normal sperm morphology (sperm without visible defects).
  • These results are similar to several earlier studies showing that men eating a healthy diet have greater sperm count and sperm quality.

The authors concluded: “Our findings support the evidence that adhering to generally healthy diet patterns is associated with better semen quality and more favorable markers of testicular function. Because diet is modifiable, these results suggest the possibility of using dietary intervention as a potential approach to improving testicular function in men of reproductive age.”

Do Real Men Eat Meat?

SteakNow it is time to come back to the original question, “Do real men eat meat”. Or more specifically, does red meat consumption increase virility? Of course, the whole question of whether a single food affects virility, or any other aspect of manliness, is bogus.

Individual foods don’t affect our health. Diets do. So, let’s review how diets affect men’s sperm count and sperm quality.

  • The highest sperm count and sperm quality was associated with the prudent diet. This diet relied primarily on fish and chicken as protein sources but did not exclude red meat. It was also a diet high in vegetables, fruits, nuts, and water (in place of sugary beverages).
  • The second highest sperm count and sperm quality was associated with the vegetarian diet. This diet relied on beans and eggs as the primary protein sources. It specifically excluded red meat and chicken but did not exclude fish. It was also high in fruits and nuts. Soy milk, tea, and coffee were the main beverages.
  • The third highest sperm count and sperm quality was associated with the Danish diet. This diet relied on cold processed meats (some of which were red meats), cold fish, and dairy for protein. However, it also was rich in whole grains and fruits. Water and sugary beverages were consumed in equal proportions.
  • The lowest sperm count and sperm quality was associated with the Western diet. This diet relied on red and processed meats as the primary protein source. However, it was also high in refined grains, snacks, sugary beverages, sweets, and junk foods.

So, if we are using sperm count and sperm quality as a measure of virility, it is clear that real men don’t eat red meat. Or put another way, a diet rich in red meat is more likely to reduce sperm count and sperm quality than it is to increase it.

However, a small amount of red meat as part of an overall healthy diet can be consistent with good sperm count and quality.

In short, diet does affect sperm quality. For example, based on this study:

  • An 8-ounce steak with French fries, cherry pie, and a soft drink (or, in our part of the country, sweet tea) may not be good for your sex life.
  • If you don’t want to give up red meat, a better choice might be 3-ounces of steak in a vegetable stir fry, fruit for dessert, and water or tea as your beverage.
  • If you want to maximize sperm count and sperm quality, an even better choice would be chicken, fish, or beans with vegetables, fruit for dessert, and water or tea as your beverage.

The Bottom Line

Meat has a certain mystique among some men. They believe real men eat meat, especially red meat. The belief is that eating red meat makes them bigger, stronger, and more virile.

How much of that is true. We already know that meat has no magical power to make men bigger and stronger. But what about virility? Does meat make men more virile? Fortunately, we now have an answer to that question. A recent study has looked at the effect of diet on sperm count and sperm quality.

  • The highest sperm count and quality was associated with a prudent diet. This diet relied primarily on fish and chicken as protein sources but did not exclude red meat. It was also a diet rich in vegetables, fruits, nuts, and water (in place of sugary beverages). In other words, it was a healthy diet.
  • The lowest sperm count and quality was associated with the Western diet. This is a diet that relies on red and processed meats as the primary protein source. However, it is also high in refined grains, snacks, sugary beverages, sweets, and junk foods.

So, if we are using sperm count and sperm quality as a measure of virility, it is clear that real men don’t eat red meat. Or put another way, a diet rich in red meat is more likely to reduce sperm count and quality than it is to increase it.

However, a small amount of red meat as part of an overall healthy diet can be consistent with good sperm count and sperm quality.

In short, it appears that diet does affect sperm quality:

  • An 8-ounce steak with French fries, cherry pie, and a soft drink (or, in our part of the country, sweet tea) may not be good for your sex life.
  • If you don’t want to give up red meat, a better choice might be 3-ounces of steak in a vegetable stir fry, fruit for dessert, and water or tea as your beverage.
  • If you want to maximize sperm count and sperm quality, an even better choice would be chicken, fish, or beans with vegetables, fruit for dessert, and water or tea as your beverage.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Why Do Most Diets Fail?

How To Lose Weight And Keep It Off

New Year DietTomorrow is the official start of another dieting season. Millions of Americans will be making a New Year’s Resolution to lose weight. The top three reasons for these weight loss resolutions are:

1)    Reduce disease risk (73%). After all, we are being told those excess pounds increase our risk of diabetes, heart disease, cancer, and just about every other disease known to man.

2)    Improve self-esteem (61%). Some of this may be due to the social stigma associated with obesity, but many people simply want to improve the image they see in the mirror every morning when they get out of the shower.

3)    Boost energy (49%).

Those are all good reasons for losing weight. But before you make your New Year’s resolution to embark on another weight loss journey, you should ask yourself “Do weight loss diets work?” If you look at the statistics, they aren’t very encouraging:

1)    45 million Americans go on a weight loss diet every year.

·       50% go on fad diets.

·       They spend $33 billion on weight loss products.

·       90% regain almost all the weight. That’s called the yo-yo effect.

·       On average, Americans gain 11 pounds on every diet yo-yo.

o   They might as well have thrown that $33 billion to the wind.

2)    228,000 Americans get gastric bypass surgery.

·       80% regain almost all the weight.

o   Their digestion and their health will never be the same.

As if those statistics weren’t bad enough, the obesity epidemic gets worse year after year (see the graphic on the Obesity Epidemicright). Americans keep getting fatter. What we are doing clearly isn’t working.

You are probably saying to yourself: “I know that, but this year I’m going to try a new diet.” As the saying goes “Hope springs eternal in the human breast”, but is it realistic to think this time will be different?

Let me share a quote from a book and TV series called “The Weight Of the Nation” by John Hoffman & Dr. Judith Salerno”:

“First we blamed fat – low fat diets didn’t work! Then we blamed carbs, eggs, red meat, dairy, white flour, sugar, juices, sodas, high-fructose corn syrup, & partially hydrogenated fats. One by one, we replaced the evil food du jour…and watched our collective waistlines grow.”

In other words, they are saying it’s not just low-fat diets that don’t work. None of the popular diets work long term. I come across lots of people who tell me the Atkins weight-loss diet works best for them. That would be convincing if they were slender, but they aren’t! They gained it all back and then some. Now that the keto diet has been around for a few years, I am starting to see the same pattern there as well.

Clearly, the problem isn’t losing the weight. Any diet can help you lose weight. The problem is keeping the weight off. Let’s look at why this is.

Why Do Most Diets Fail?

WhyTo understand the answer to this question, let’s start with another quote from “The Weight Of the Nation”: “Our bodies were designed to store fat in times of plenty and retain fat in times of famine”

Essentially, the authors were saying when our ancestors were hunters and gatherers, there were times when food was abundant, and times when food was scarce. In order to survive, our bodies had to store energy in its most efficient form when food was abundant and hold on to those energy stores as long as possible when food was scarce.

Fat provides more than twice as many calories per gram as either carbohydrate or protein. Additionally, our ability to store carbohydrate is limited. And we don’t really have protein stores. All the proteins in our body have essential functions. However, our ability to store fat is unlimited. Now you understand why fat is the preferred energy store in times of plenty and our bodies try to hold on to it as long as possible in times of famine.

With that perspective in mind, there are three reasons why most diets fail:

1)    Most dieters are looking for rapid weight loss (at least 2-5 pounds/week). That is a problem because “Our bodies were designed to…retain fat in times of famine”. When we lose weight quickly, our bodies interpret that as famine. Our bodies respond by decreasing our metabolic rate so we can hold on to those fat stores.

The solution to this problem is to set more reasonable weight loss goals. If we keep the rate of weight loss in the 1-2 pound/week range (0.5-1 pounds/week is even better), we can largely avoid this famine response. You should ask yourself, “What’s the rush?” After all, the average American only gains 1-2 pounds/year. Why do we need to get rid of that excess weight in just a few weeks?

2)    Most dieters are looking for significant weight loss (more than 20 pounds). That is a problem because our bodies are designed to retain fat stores, not protein stores. When our bodies sense a famine they burn our protein stores (lean muscle mass) to spare as much of our fat stores as possible. The longer the diet (famine) lasts, the more muscle mass we lose.

That’s a problem because muscle burns calories much faster than fat. The more muscle we lose, the more our metabolic rate decreases. It gets harder and harder to lose weight, and eventually we reach a plateau. Most people get discouraged at that point and go off their diet.

That’s where the other part of the quote from “The Weight Of The Nation” kicks in: “Our bodies are Yo-Yo with Boydesigned to store fat in times of plenty”. Once again, it is fat we store, not protein. Most people never regain the protein stores they lost, so their metabolic rate remains low. They regain most of the weight they lost, and then some. This is the origin of the yo-yo effect.

There are two solutions to this problem:

·       Increase your resistance exercise and your intake of protein with high levels of the essential amino acid leucine. I have covered this in a previous issue of “Health Tips From The Professor”.

·       Set more reasonable weight loss goals. It is possible to lose more than 20 pounds without losing muscle mass. We just need to think in terms of reaching those weight loss goals in years rather than in months. Once again, remember it took us years to gain the weight. Why not think in terms of years to lose the weight?

3)    Most dieters think in terms of diets rather than lifestyle change. Diets have an expiration date. Then most people just drift back to “the way they really live”. Lifestyle change, on the other hand, is permanent. Once we change to a healthier lifestyle, we no longer need to focus on weight loss. The weight comes off automatically.

To better understand the power of lifestyle change let’s look at something called “The National Weight Control Registry”.

How To Lose Weight And Keep It Off

Happy woman on scaleRather than focus on the abysmal statistics for long-term weight loss, doctors Rena Hill and James O Wing decided to focus on the characteristic of people who manage to keep their weight off. They founded something called “The National Weight Control Registry” and invited people who were successful at keeping the weight off to participate in their program.

Currently, the National Weight Control Registry is tracking over 10,000 individuals who have lost 30 pounds or more and have kept it off for long periods of time. They use detailed questionnaires and annual follow-up surveys to study the behavioral and psychological characteristics and the strategies of weight loss maintainers.

When you look at how they lost weight, they are a very diverse group:

·       They lost weight on every possible diet – from vegan to keto to just plain crazy.

·       50% lost weight on commercial diet programs. 50% lost weight on their own.

·       Some lost weight quickly. Some lost weight slowly.

When you look at weight maintenance, you realize that the dismal weight maintenance statistics don’t have to apply to you. The good news is:

·       On average, people in The National Weight Control Registry have lost 66 pounds and have kept it off for 5 years or more.

·       12-14% of them have maintained a weight loss of 100 pounds or more for 5 or more years.

·       Even better, once they maintained their weight loss for 2-5 years, it became easy.

They no longer had to battle hunger and a sluggish metabolism. They no longer had to think about the lifestyle changes they were trying to maintain. Their new lifestyle became what they did automatically, without even thinking about it. Their weight loss had become permanent.

By now, you are probably wondering how they do it. Here are the top 7 characteristics of those who are successfulhealthy living at keeping the weight off:

1)    They consumed reduced calorie, low-fat, healthy diets.

2)    They had internalized their eating patterns. It had become how they ate every day without even thinking about it.

3)    They monitored their weight regularly. This allowed them to make adjustments whenever they saw their weight start to creep up.

4)    They ate breakfast on a regular basis.

5)    They got lots of exercise (on average, about 1 hour/day).

6)    They watched less than 10 hours of TV/week. If you were wondering where you would find the time to exercise an hour/day, this is probably your answer.

7)    They were consistent. They had no planned “cheat days”. This doesn’t mean they were purists. They still allowed themselves to eat some of their favorite unhealthy foods on an occasional basis. They just didn’t set aside regular times when they planned to “pig out”.

There was one other interesting observation from this study:

·       Those who used meal replacement shakes as part of their weight loss, focused more on diet and included meal replacement shakes as part of their maintenance program.

·       Those who lost weight on their own, also followed healthy eating habits, but put a bit more emphasis on exercise to keep themselves on track.

·       Both approaches were effective.

The take-home message of the National Weight Control Registry is clear. There is no magic diet that guarantees you will keep the weight off. The “secret” to keeping the weight off is a healthy eating pattern and a healthy lifestyle.

In short, if your resolution is to lose weight next year, don’t focus on the diet you will follow to lose the weight. Instead, focus on the healthy lifestyle you will follow to keep the weight off.

Of course, you will be most successful if the diet you are following to lose weight incorporates the healthy lifestyle you plan to follow to maintain your weight loss.

What Role Do Habits Play In Weight Loss?

Habits-Old-vs-NewFinally, I would like to share a recent study (G Cleo et al, International Journal of Obesity, 43: 374-383, 2019) that puts the whole issue of weight loss and weight maintenance in a different perspective. This study looked at the role that habits play in weight loss.

In short, the study enrolled 130 participants who wanted to lose weight. All the participants were told this was a weight loss study, but none of the participants were given detailed diet and exercise recommendations to follow. The study had a 12-week intervention phase followed by a 12-month follow-up phase. The participants were divided into three groups.

1)    Group 1 received no advice during the intervention phase. This was the control group.

2)    Group 2 focused on breaking old habits. During the intervention phase they were sent daily tests suggesting new habit patterns. These were suggestions like “Drive a different route to work today”. None of the texts had anything to do with diet or lifestyle.

3)    Group 3 focused on creating new healthy habits. They were given a list of 10 healthy habits. During the intervention phase they were asked to log how many of these habits they implemented each day. The 10 healthy habits were:

#1: Keep to a daily meal routine.

#2: Choose reduced fat versions of foods.

#3: Walk off the weight (aim for 10,000 steps/day).

#4: Pack a healthy snack (Choose healthy options such as fruits, nuts, or low-fat yogurt).

#5: Read labels.

#6: Be cautious with your portions.

#7: Break up your sitting time (Stand for 10 minutes every hour).

#8: Think about your drinks (Choose water instead of sodas and fruit juices).

#9: Focus on your food (Slow down. Don’t eat while watching TV).

#10: Don’t forget your 5 servings of fruits and vegetables a day.

The results were:

·       People in both habit change groups lost significantly more weight than people in the control group.

·       People in the habit change groups continued to lose weight for 12 months after the intervention ended.

·       Weight loss was essentially identical in the two habit change groups.

The last observation is particularly interesting. Remember that one of the habit change groups was simply focused on breaking old habits, yet people in this group did just as well as people who were taught healthy lifestyle habits. This implies that people already know about healthy lifestyle habits. They just don’t know how to break their old habits. Once they become comfortable breaking old habits, they find it easy to adopt healthier lifestyle habits.

In short, change your habits, change your lifestyle. Change your lifestyle, control your weight.

What Does This Mean For You?

why-do-most-dirts-failI covered a lot of information in this article. Let me sum it up by giving you my top 10 tips for losing weight and keeping it off.

1)    You don’t need to achieve your “ideal weight”. Losing 5-10% of your body weight may be enough.

2)    Ditch diets. Focus on lifestyle change.

3)    Slow and steady wins the day.

4)    Change your habits, change your weight.

5)    Long-term weight loss is possible.

6)    Low-fat, healthy eating patterns are best.

7)    Once you have internalized healthy habits, they become automatic.

8)    If you stick with a healthy lifestyle long enough, keeping the weight off becomes easy.

9)    Focus on all the healthy food choices you have, not what you have to give up. There is a cornucopia of great tasting, healthy foods to choose from.

10)  Never say never. Allow yourself to enjoy your old favorite foods on occasion. Just don’t make it a habit.

The Bottom Line

I cover a lot of information in this article. Let me sum it up by giving you my top 10 tips for losing weight and keeping it off.

1)    You don’t need to achieve your “ideal weight”. Losing 5-10% of your body weight may be enough.

2)    Ditch diets. Focus on lifestyle change.

3)    Slow and steady wins the day.

4)    Change your habits, change your weight.

5)    Long-term weight loss is possible.

6)    Low-fat, healthy eating patterns are best.

7)    Once you have internalized healthy habits, they become automatic.

8)    If you stick with a healthy lifestyle long enough, keeping the weight off becomes easy.

9)    Focus on all the healthy food choices you have, not what you have to give up. There is a cornucopia of great tasting, healthy foods to choose from.

10)  Never say never. Allow yourself to enjoy your old favorite foods on occasion. Just don’t make it a habit.

For more details on how to lose weight and keep it off, read the article above. In fact, if you plan to lose weight in the coming year, you should really read this article first.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

 

 

Do Vegetarians Have A Higher Risk Of Stroke?

What Are The Benefits And Risks Of A Vegetarian Diet?

Vegetarian FoodsVegetarian diets are thought to be very healthy. Clinical studies show that vegetarian diets are associated with decreased risk of heart disease, diabetes, cancer, Alzheimer’s disease, and much more. What’s not to like?

That’s why the recent headlines claiming that vegetarian diets may increase the risk of stroke were so surprising. Advocates of meat-heavy diets like the Paleo and Keto diets were overjoyed. These results fit in with their view that we should be eating more meat protein and less plant protein. Nutrition experts, on the other hand, were asking: “What’s going on?” “How can this be?”

Those of you who are regular readers of “Health Tips From the Professor” know that I am an advocate of primarily plant-based diets. Thus, I felt a responsibility to analyze the study (TYN Tong et al, British Medical Journal, 366: 14897, 2019) behind the headlines impartially and give you, my readers, clear guidelines for the healthiest possible diet.

How Was The Study Done?

clinical-studyLet’s start with some background:

·       A major study called the “European Prospective Investigation Into Cancer and Nutrition” (EPIC) has been underway since the early 90’s.

·       The British component of this study is known as the EPIC-Oxford study.

·       While the study has “cancer” in it’s title, it was designed to measure the impact of nutrition on many diseases. In this case, the study focused on heart disease and stroke.

·       Finally, enrollment in the EPIC-Oxford study was designed to give a high proportion of vegetarians in the study population.

The EPIC-Oxford study enrolled 48,188 participants with no previous history of heart disease, stroke, or angina between 1993 and 2001. A detailed diet analysis was performed upon enrollment and again in 2010. Based on these data, the participants were divided into three groups:

1)    Meat eaters (24,428 participants).

2)    Fish eaters (7,506 participants). This group consumed fish but no other meats. People with this eating style are often called pescatarians.

3)    Vegetarians (16, 254 participants). This group consumed dairy and eggs, but no meat. People with this eating style are often called lacto-ovo vegetarians.

4)    The diet analysis also identified participants who were vegans (no animal foods). However, this group was too small to obtain statistically significant comparisons, so they were included with the lacto-ovo vegetarians in the vegetarian group.

Data on heart disease and stroke were obtained from the UK’s health service records through March 31st, 2016. The average time of follow-up for participants in the study was 18.1 years.

Without going into greater detail, this was a very large, well-designed study.

How Did The Diets Of The Three Groups Compare?

balance scaleThe first step in analyzing this study is to ask how the diets of the three groups compared.

Compared to meat eaters, the fish eaters consumed:

·       No meat other than fish.

·       Slightly less milk and significantly more cheese.

·       Slightly more fruits & vegetables.

·       Significantly more legumes & soy foods, nuts & nut butter.

·       Slightly more carbohydrate and slightly less protein.

·       Slightly less saturated fat and slightly more polyunsaturated fat.

·       Around 260 fewer calories per day.

Compared to fish eaters, the vegetarians consumed:

·       No meat.

·       Slightly less milk & cheese.

·       About the same amount of fruits & vegetables.

·       Significantly more legumes & soy foods, nuts & nut butter.

·       Slightly more carbohydrate and slightly less protein.

·       About the same saturated and polyunsaturated fat.

·       Around 125 fewer calories per day.

On average, the vegetarians consumed about 1 cup of milk and one ounce of cheese per day. The fish eaters consumed 1.4 ounces of fish per day.

In terms of comparisons:

·       The biggest differences were between the fish eaters and the meat eaters. It would be fair to say that the fish eaters consumed a primarily plant-based diet with added fish and dairy.

·       The biggest differences between the vegetarians and fish eaters was that the fish eaters got a significant percentage of their protein from fish, while the vegetarians got a significant amount of their protein from plant sources. Otherwise, their diets were fairly comparable.

Finally, the 10-year follow-up diet analysis showed that most participants stuck with their initial diet.

Do Vegetarians Have A Higher Risk Of Stroke?

strokeNow, for the study results:

·       Compared to meat eaters, fish eaters had 13% lower risk of heart disease, and vegetarians had a 22% lower risk of heart disease.

o   For vegetarians this corresponds to 10 fewer cases of heart disease per 1,000 people over 10 years.

·       Compared to meat eaters, vegetarians had a 20% higher risk of stroke, mostly due to an increased risk for hemorrhagic stroke.

o   For vegetarians this corresponds to 3 additional cases of stroke per 1,000 people over 10 years.

·       The risk of stroke was essentially identical for fish eaters and meat eaters.

In many other aspects, vegetarians were healthier than meat-eaters. For example, they:

·       Weighed less.

·       Had lower blood pressure.

·       Had lower total and LDL cholesterol.

·       Were less likely to have developed diabetes during the study.

·       Were less likely to have required long-term treatment for other illnesses.

What Are The Strengths And Weaknesses Of The Study?

strengths-weaknessesThe strength of this study is obvious. It was a very large, well-designed study. The study also lasted a long time. Participants in the study were followed for almost 20 years.

There are two clear weaknesses, however:

1)    Numerous previous studies have confirmed that vegetarian diets decrease heart disease risk by about 20%. However, none of those previous studies have reported an increase in stroke risk. This study is an outlier.

2)    There is no clear mechanism that explains why a vegetarian diet might increase stroke risk. Based on previous observations that statin drugs increase the risk of hemorrhagic stroke, the authors suggested the increased stroke risk might be due to lowered LDL cholesterol levels.

This mechanism is speculative at present. Furthermore, if true, it would suggest that any intervention (drug or nutritional) that lowers LDL cholesterol would increase stroke risk.

In the words of the authors:

·       “The present study has shown that British adults who were fish eaters or vegetarians had lower risks of heart disease than meat eaters, but that vegetarians had higher risks of stroke.

·       Future work should include further measurements…to identify which factors may cause the observed associations. [In plain English: We need to understand how vegetarian diets might increase stroke risk before we put too much weight on the results of this study.]

·       Additional studies in other large-scale cohorts with a high proportion of non-meat eaters are needed to confirm the generalizability of these results and assess their relevance for clinical practice and general health.” [In plain English: More studies are needed to confirm this observation before we start changing our recommendations about what constitutes a healthy diet.]

What Are The Benefits And Risks Of A Vegetarian Diet?

benefits-risksLet’s assume for a minute that the results of this study are accurate and take a closer look at the benefits and risks of a vegetarian diet. Here is my assessment:

1)    This report is troubling, but it may not be correct. The association of vegetarian diets with a slight increase in stroke risk has only been seen in a single study. This study needs to be confirmed before we become too concerned about vegetarianism increasing stroke risk.

2)    On the balance, vegetarian diets should still be considered very healthy. They lower the risk of heart disease, high blood pressure, diabetes, some cancers, inflammatory diseases and possibly even Alzheimer’s disease.

3)    However, I have often said that we have 5 food groups for a reason, and it is not a good idea to eliminate whole food groups. In the past, I have used that statement to critique diets that leave out important plant food groups like fruit, whole grains, and legumes.

If the data on stroke risk in this study are true, it suggests it might also not be a good idea to leave out meat. However, you don’t need a lot of meat. The fish eaters in this study were consuming 1.4 ounces of fish per day. That was enough to eliminate the increased risk of stroke.

4)    In addition, you don’t have to be a vegan purist to enjoy the health benefits of a primarily plant-based diet. As I describe in my book, “Slaying The Food Myths”, primarily plant-based diets ranging from vegan through pescatarian and semi-vegetarian to Mediterranean and DASH are all incredibly healthy.

I personally follow a semi-vegetarian diet but often recommend Mediterranean and DASH diets to others because they are the easiest primarily plant-based diets for the average American to follow.

5)    Finally, if you have a family history, or are at high risk, of stroke, I recommend prudence until we know more. You may wish to adopt a version of primarily plant-based diets that incorporates some meat (That would be in the pescatarian to DASH range of primarily plant-based diets). Your heart will thank you, and you won’t increase your risk of stroke.

The Bottom Line

A recent study enrolled 48,188 British adults; divided them into meat eaters, fish eaters, and vegetarians; followed them for 18.1 years; and looked at their risk for heart disease and stroke. The results were:

·       Compared to meat eaters, fish eaters had 13% lower risk of heart disease, and vegetarians had a 22% lower risk of heart disease.

o   For vegetarians this corresponds to 10 fewer cases of heart disease per 1,000 people over 10 years.

·       Compared to meat eaters, vegetarians had a 20% higher risk of stroke, mostly due to an increased risk for hemorrhagic stroke.

o   For vegetarians this corresponds to 3 additional cases of stroke per 1,000 people over 10 years.

·       The risk of stroke was essentially identical for fish eaters and meat eaters.

Here is my perspective:

1)    This report is troubling, but it may not be correct. The association of vegetarian diets with a slight increase in stroke risk has only been seen in a single study. This study needs to be confirmed before we become too concerned about vegetarianism increasing stroke risk.

2)    On the balance, vegetarian diets should still be considered very healthy. They lower the risk of heart disease, high blood pressure, diabetes, some cancers, inflammatory diseases and possibly even Alzheimer’s disease.

3)    However, I have often said that we have 5 food groups for a reason, and it is not a good idea to eliminate whole food groups. In the past, I have used that statement to critique diets that leave out important plant food groups like fruit, whole grains, and legumes.

If the data on stroke risk in this study are true, it suggests it might also not be a good idea to leave out meat. However, you don’t need a lot of meat. The fish eaters in this study were consuming 1.4 ounces of fish per day. That was enough to eliminate the increased risk of stroke.

4)    In addition, you don’t have to be a vegan purist to enjoy the health benefits of a primarily plant-based diet. As I describe in my book, “Slaying The Food Myths” (https://slayingthefoodmyths.com), primarily plant-based diets ranging from vegan through pescatarian (the fish eaters in this study) and semi-vegetarian to Mediterranean and DASH are all incredibly healthy.

I personally follow a semi-vegetarian diet but often recommend Mediterranean and DASH diets to others because they are the easiest primarily plant-based diets for the average American to follow.

5)    Finally, if you have a family history, or are at high risk, of stroke, I recommend prudence until we know more. You may wish to adopt a version of primarily plant-based diets that incorporates some meat (That would be in the pescatarian to DASH range of primarily plant-based diets). Your heart will thank you, and you won’t increase your risk of stroke.

For more details on the study and what it means for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Is The Paleo Diet Bad For Your Heart?

Is The Paleo Diet Bad For Your Gut?

the paleo dietThere is a lot to like about the Paleo diet:

·       It is a whole food diet. Any diet that eliminates sodas, junk foods, and highly processed foods is an improvement over the American diet.

·       It includes lots of vegetables and some fruits.

·       It helps you lose weight, and any diet that results in weight loss improves your blood work – things like cholesterol, triglycerides, blood sugar control and more.

However, there are concerns the Paleo diet may not be healthy long term.

·       In part, that is because the diet is high in meat, red meat, and saturated fat.

·       Equally important, however, is what the diet eliminates – namely whole grains, legumes (beans), and dairy.

Those of you who have read my book, “Slaying The Food Myths”, know that I say: “We have 5 food groups for a reason”. This is particularly true for the plant food groups. That’s because each plant food group provides a unique blend of:

·       Vitamins and minerals. Those can be replaced with good multivitamin/multimineral supplement.

·       Phytonutrients. You can only get the full complement of health-promoting phytonutrients from a variety of foods from all 5 food groups.

·       Fiber. There are many kinds of fiber and they each play different roles in our intestine. You can only get all the health-promoting varieties of fiber by consuming fruits, vegetables, whole grains and legumes.

·       Gut bacteria. What we call fiber, our gut bacteria call food. Each of the plant food groups supports different populations of friendly gut bacteria.

Based on this reasoning, one might suspect that the Paleo diet might alter our gut bacteria in ways that could be bad for our health. Until recently, this sort of reasoning was just a theoretical concern. That’s because:

1)    We knew far too little about the health effects of different populations of bacteria. This is rapidly changing. Several recent studies have systematically investigated the connection between gut bacteria and health outcomes.

2)    We knew our diet influenced the bacteria populations found in our gut, but we had no understanding of how these changes might influence our health. This too is changing. The study (A Genoni et al, European Journal of Nutrition, https://doi.org/10.1007/s00394-019-02036-y) I discuss this week is an excellent example of recent studies linking diet, gut bacteria, and risk factors for disease.

How Was The Study Done?

can you believe clinical studies doctorThis study recruited 91 participants from Australia and New Zealand. It was a very well designed study in that:

·       The Paleo diet group (44 participants) was recruited based on self-proclaimed adherence to the Paleo diet (< 1 serving/day of grains and dairy products) for one year or more. This is important because short term effects of switching to a new diet are confounded by weight loss and other factors.

o   After analyzing the diets of the Paleo group, the investigators found it necessary to subdivide the group into Strict Paleo (< 1 serving/day of grains and dairy products) and Pseudo-Paleo (> 1 serving/day of grains and dairy).

·       The control group (47 participants) was recruited based on self-proclaimed adherence to a “healthy diet” for 1 year or more with no change in body weight (A healthy diet was defined as a whole food diet containing a variety of foods from all 5 food groups). This is important because far too many studies compare the diet they are promoting to an unhealthy diet with a lot of sugar and highly processed junk foods. These studies provide little useful information because almost anything is better than an unhealthy diet.

·       The participants completed a diet survey based on the frequency of consumption of various foods during the previous year. However, because diet surveys based on the recollection of participants can be inaccurate, the investigators used two rigorous tests to validate the accuracy of those diet surveys.

o   The first was a 3-day weighed dietary record (WDR). Simply put, this means that participants weighed and recorded all foods and beverages before they were eaten for 3 days. Two of those days were weekdays, and one was a weekend day.

o   Secondly, the investigators used blood, urine, and metabolic measures to independently determine protein and energy intake of each participant. Participants who were identified by these means as under reporting both protein and energy were considered unreliable dietary reporters and were excluded from the analysis.

o   It is very rare to find a study that goes to this length to validate the accuracy of the dietary data used in their analysis.

The participants also provided blood, urine and stool samples and completed a physical activity assessment.

What Were The Differences Between The Paleo Diet And The Healthy Control Diet?

Paleo FoodsOnly the Strict Paleo Diet group was faithfully following the Paleo diet. In addition, most of the results with the Pseudo Paleo Diet Group were intermediate between the other two diets. Therefore, to simplify my discussion of this study I will only compare the Strict Paleo Diet group, which I refer to as the Paleo Diet group, with the Healthy Diet control group.

The Paleo diet emphasizes fresh vegetables, especially green leafy vegetables, and discourages grains. Thus, it is no surprise that:

·       The Paleo Diet group ate 74% more vegetables and 3 times more leafy green vegetables than the Healthy Diet group.

·       The Paleo Diet group ate only 3% of the grains and 3% of the whole grains compared to the Healthy Diet group.

The Paleo diet encourages consumption of meat and eggs and discourages consumption of dairy and plant proteins. Thus, it is not surprising that:

·       The Paleo Diet group ate 3 times more red meat and 5 times more eggs than the Healthy Diet group.

·       The Paleo Diet group ate 10% of dairy foods compared to the Healthy Diet group.

·       The Paleo Diet group consumed two times more saturated fat and cholesterol than the Healthy Diet group.

The most interesting comparison between the two diets was the following:

·       Intake of total fiber, insoluble fiber, and soluble fiber was comparable on the two diets.

·       However, intake of resistant starch was 50% lower in the Paleo Diet group. This is significant because:

o   Resistant starch is a type of fiber found primarily in whole grains, legumes, potatoes, and yams (Potatoes and yams are also dietary “no nos” on most low-carb diets).

o   Resistant starch is an especially good food for certain species of healthy gut bacteria.

Is The Paleo Diet Bad For Your Gut?

Bas BacteriaBecause resistant starch affects gut bacteria, the study next looked at the effect of the two diets on the populations of gut bacteria. This is where the story starts to get interesting. When they looked at different groups of gut bacteria, they discovered that:

·       Bifidobacteria were much more abundant in the Healthy Diet group than in the Paleo Diet group, and the amount of Bifidobacteria in the gut was directly proportional to the amount of whole grains in the diet.

o   This is important because previous studies have suggested Bifidobacteria help maintain intestinal barrier integrity and protect against irritable bowel syndrome and obesity.

·       Roseburia were also much more abundant in the Healthy Diet group and proportional to the amount of whole grains in the diet.

o   This is important because previous studies have suggested Roseburia protect against inflammatory bowel diseases like Crohn’s disease and ulcerative colitis.

·       Hungatella were much more abundant in the Paleo Diet group and were inversely proportional to the amount of whole grains in the diet.

o   This is important because Hungatella metabolize carnitine and choline, which are found in meats (especially red meats), egg yolks, and high fat dairy, into a compound called trimethylamine or TMA. TMA is then further metabolized in the liver to trimethylamine-N-oxide, or TMAO.

o   TMAO is a bad player. It is positively associated with heart disease, stroke, kidney disease, diabetes, and Alzheimer’s disease. However, the evidence is strongest for heart disease. TMAO has been called an independent risk factor for cardiovascular death.

Because of this, the study looked at TMAO levels in the blood of the two diet groups. These results were concerning:

·       TMAO levels were 2.5-fold higher in the Paleo Diet group than in the Healthy Diet group.

·       As might be expected, TMAO levels were positively correlated with red meat intake and inversely proportional to whole grain intake.

Is The Paleo Diet Bad For Your Heart?

heart diseaseWhen you put all the evidence together you have a compelling argument that the Paleo diet is likely to increase the risk of heart disease. Let me summarize the data briefly:

1)    The Paleo diet discourages the consumption of whole grains.

2)    Whole grains are a major source of a dietary fiber called resistant starch.

3)    Because the Paleo diet is low in resistant starch, it causes a decrease in two healthy types of gut bacteria and an increase in a type of gut bacteria called Hungatella.

4)    Hungatella metabolize compounds found in meat, eggs, and dairy to a precursor of a chemical called TMAO. This study showed that TMAO levels were 2.4-fold higher in people consuming a Paleo diet.

5)    TMAO is associated with coronary artery disease and is considered an independent risk factor for cardiovascular death.

The authors of the study concluded: “Although the Paleo diet is promoted for improved gut health, results indicate long-term adherence is associated with different gut microbiota and increased TMAO. A variety of fiber components, including whole grain sources, may be required to maintain gut and cardiovascular health.”

Of course, studies like this are looking at associations. They are not definitive. What we need are long term studies looking at the effect of the Paleo diet on heart disease outcomes like heart attack and stroke. Until we have these studies my advice is:

·       Don’t accept claims that the Paleo diet is heart healthy. There are no long-term clinical studies to back up that claim.

·       Be aware that the Paleo diet affects your gut bacteria in ways that may be bad for your heart.

The more we learn about our gut bacteria, the more we appreciate the importance of including all 5 food groups in our diet, especially all the plant food groups.

Are Low Carb Diets Healthy?

low carb dietThe Paleo diet is not the only diet that is high in red meat and low in whole grains. The same is true for virtually all the popular low-carb diets. There are studies showing other low-carb diets also alter gut bacteria and raise TMAO levels, so there is a similar concern that they may also increase the risk of heart disease.

This is in addition to concerns about the high saturated fat consumption which increases the risk of heart disease and red meat consumption, which may increase the risk of certain cancers.

Finally, there are no studies showing that any low-carb diet is healthy long term, even the Atkins diet, which has been around for more than 50 years. Until we have long-term studies about the health consequences of low-carb diets, my advice is similar to that for the Paleo diet.

·       Don’t accept claims that low-carb diets are healthy. There are no long-term clinical studies to back up that claim.

·       Be aware that low-carb diets affect your gut bacteria in ways that may be bad for your health.

The Bottom Line

A recent study looked at the effect of the Paleo diet on an important risk factor for heart disease. Here is a brief summary of the data:

1)    The Paleo diet discourages the consumption of whole grains.

2)    Whole grains are a major source of a dietary fiber called resistant starch.

3)    Because the Paleo diet is low in resistant starch, it causes a decrease in two healthy types of gut bacteria and an increase in a type of gut bacteria called Hungatella.

4)    Hungatella metabolize compounds found in meat, eggs, and dairy to a precursor of a chemical called TMAO. This study showed that TMAO levels were 2.4-fold higher in people consuming a Paleo diet.

5)    TMAO is associated with coronary artery disease and is considered an independent risk factor for cardiovascular death.

Of course, studies like this are looking at associations. They are not definitive. What we need are long term studies looking at the effect of the Paleo diet on heart disease outcomes – like heart attack and stroke. Until we have these studies my advice is:

·       Don’t accept claims that the Paleo diet is heart healthy. There are no long-term clinical studies to back up that claim.

·       Be aware that the Paleo diet affects your gut bacteria in ways that may be bad for your heart.

·       Virtually all the popular low-carb diets discourage consumption of whole grains, so my advice for them is the same as for the Paleo diet.

The more we learn about our gut bacteria, the more we appreciate the importance of including all 5 food groups in our diet, especially all the plant food groups.

For more details on the study and what it means for you, read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease

Health Tips From The Professor