Plant-based Diets

Can Healthy Eating Help You Lose Weight?

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Who Benefits Most From A Healthy Diet?

Author: Dr. Stephen Chaney 

fad dietsFad diets abound. High protein, low carb, low fat, vegan, keto, paleo – the list is endless. They all claim to be backed by scientific studies showing that you lose weight, lower your cholesterol and triglycerides, lower your blood pressure, and smooth out your blood sugar swings.

They all claim to be the best. But any reasonable person knows they can’t all be the best. Someone must be lying.

My take on this is that fad diet proponents are relying on “smoke and mirrors” to make their diet look like the best. I have written about this before, but here is a brief synopsis:

  • They compare their diet with the typical American diet.
    • Anything looks good compared to the typical American diet.
    • Instead, they should be comparing their diet with other weight loss diets. That is the only way we can learn which diet is best.
  • They are all restrictive diets.
    • Any restrictive diet will cause you to eat fewer calories and to lose weight.
    • As little as 5% weight loss results in lower cholesterol & triglycerides, lower blood pressure, and better control of blood sugar levels.

Simply put, any restrictive diet will give you short-term weight loss and improvement in blood parameters linked to heart disease, stroke, and diabetes. But are these diets healthy long term? For some of them, the answer is a clear no. Others are unlikely to be healthy but have not been studied long term. So, we don’t know whether they are healthy or not.

What if you started from the opposite perspective? Instead of asking, “Is a diet that helps you lose weight healthy long term?”, what if you asked, “Can healthy eating help you lose weight?” The study (S Schutte et al, American Journal of Clinical Nutrition, 115: 1-18, 2022) I will review this week asked that question.

More importantly, it was an excellent study. It compared a healthy diet to an unhealthy diet with exactly the same degree of caloric restriction. And it compared both diets to the habitual diet of people in that area. This study was performed in the Netherlands, so both weight loss diets were compared to the habitual Dutch diet.

How Was The Study Done?

clinical studyThis was a randomized controlled trial, the gold standard of clinical studies. The investigators recruited 100 healthy, abdominally obese men and women aged 40-70. At the time of entry into the study none of the participants:

  • Had diabetes.
  • Smoked
  • Had a diagnosed medical condition.
  • Were on a medication that interfered with blood sugar control.
  • Were on a vegetarian diet.

The participants were randomly assigned to:

  • A high-nutrient quality diet that restricted calories by 25%.
  • A low-nutrient-quality diet that restricted calories by 25%.
  • Continue with their habitual diet.

The study lasted 12 weeks. The participants met with a dietitian on a weekly basis. The dietitian gave them the foods for the next week and monitored their adherence to their assigned diet. They were advised not to change their exercise regimen during the study.

At the beginning and end of the study the participants were weighed, and cholesterol, triglycerides, and blood pressure were measured.

Can Healthy Eating Help You Lose Weight?

Vegetarian DietTo put this study into context, these were not healthy and unhealthy diets in the traditional sense.

  • Both were whole food diets.
  • Both included fruits, vegetables, low-fat dairy, and lean meats.
  • Both restricted calories by 25%.

The diets were designed so that the “high-nutrient quality” diet had significantly more plant protein (in the form of soy protein), fiber, healthy fats (monounsaturated and omega-3 fats), and significantly less fructose and other simple sugars than the “low-nutrient-quality” diet.

At the end of 12 weeks:

  • Participants lost significant weight on both calorie-restricted diets compared to the group that continued to eat their habitual diet.
    • That is not surprising. Any diet that successfully restricts calories will result in weight loss.
  • Participants on the high-nutrient quality diet lost 33% more weight than participants on the low-nutrient-quality diet (18.5 pounds compared to 13.9 pounds).
  • Participants on the high-nutrient quality diet lost 50% more inches in waist circumference than participants on the low-nutrient-quality diet (1.8 inches compared to 1.2 inches).
    • This is a direct measure of abdominal obesity.

When the investigators measured blood pressure, fasting total cholesterol levels, and triglyceride levels:Heart Healthy Diet

  • These cardiovascular risk factors were significantly improved on both diets.
    • Again, this would be expected. Any diet that causes weight loss results in an improvement in these parameters.
  • The reduction in total serum cholesterol was 2.5-fold greater and the reduction in triglycerides was 2-fold greater in the high-nutrient quality diet group than in the low-nutrient-quality diet group.
  • The reduction in systolic blood pressure was 2-fold greater and the reduction in diastolic blood pressure was 1.67-fold greater in the high-nutrient quality diet group than in the low-nutrient-quality diet group.

The authors concluded, “Our results demonstrate that the nutrient composition of an energy-restricted diet is of great importance for improvements of metabolic health in an overweight, middle-aged population. A high-nutrient quality energy-restricted diet enriched with soy protein, fiber, monounsaturated fats, omega-3 fats, and reduced in fructose provided additional health benefits over a low-nutrient quality energy-restricted diet, resulting in greater weight loss…and promoting an antiatherogenic blood lipid profile.”

In short, participants in this study lost more weight and had a better improvement in risk factors for heart disease on a high-nutrient-quality diet than on a low-nutrient-quality diet. Put another way, healthy eating helped them lose weight and improved their health.

Who Benefits Most From A Healthy Diet?

None of the participants in this study had been diagnosed with diabetes when the study began. However, all of them were middle-aged, overweight, and had abdominal obesity. That means many of them likely had some degree of insulin resistance.

Because of some complex metabolic studies that I did not describe, the investigators suspected that insulin resistance might influence the relative effectiveness of the two energy-restricted diets.

To test this hypothesis, they used an assay called HOMA-IR (homeostatic model assessment of insulin resistance). Simply put, this assay measures how much insulin is required to keep your blood sugar under control.

They used a HOMA-IR score of 2.5 to categorize insulin resistance among the participants.

  • Participants with a HOMA-IR score >2.5 were categorized as insulin-resistant. This was 55% of the participants.
  • Participants with a HOMA-IR score ≤2.5 were categorized as insulin-sensitive. This was 45% of the participants.

When they used this method to categorize participants they found:

  • Insulin-resistant individual lost about the same amount of weight on both diets.
  • Insulin-sensitive individuals lost 66% more weight on the high-nutrient-quality diet than the low-nutrient-quality diet (21.6 pounds compared to 13.0 pounds).

The investigators concluded, “Overweight, insulin-sensitive subjects may benefit more from a high- than a low-nutrient-quality energy-restricted diet with respect to weight loss…”

What Does This Study Mean For You?

Questioning WomanSimply put this study confirms that:

  • Caloric restriction leads to weight loss, and…
  • Weight loss leads to improvement in cardiovascular risk factors like total cholesterol, triglycerides, and blood pressure.
    • This is not new.
    • This is true for any diet that results in caloric restriction.

This study breaks new ground in that a high-nutrient quality diet results in significantly better:

  • Weight loss and…
  • Reduction in cardiovascular risk factors…

…than a low-nutrient quality diet. As I said above, the distinction between a “high-nutrient-quality” diet and a “low-nutrient-quality” diet may not be what you might have expected.

  • Both diets were whole food diets. Neither diet allowed sodas, sweets, and highly processed foods.
  • Both included fruits, vegetables, grains, and lean meats.
  • Both reduced caloric intake by 25%.
    • If you want to get the most out of your weight loss diet, this is a good place to start.

In this study the investigators designed their “high-nutrient-quality” diet so that it contained:

  • More plant protein in the form of soy protein.
    • In this study they did not reduce the amount of animal protein in the “high-nutrient-quality” diet. They simply added soy protein foods to the diet. I would recommend substituting soy protein for some of the animal protein in the diet.
  • More fiber.
    • The additional fiber came from substituting whole grain breads and brown rice for refined grain breads and white rice, adding soy protein foods, and adding an additional serving of fruit.
  • More healthy fats (monounsaturated and omega-3 fats).
    • The additional omega-3s came from adding a fish oil capsule providing 700mg of EPA and DHA.
  • Less simple sugars. While this study focused on fructose, their high-nutrient-quality diet was lower in all simple sugars.

ProfessorAll these changes make great sense if you are trying to lose weight. I would distill them into these 7 recommendations.

  • Follow a whole food diet. Avoid sodas, sweets, and highly processed foods.
  • Include all 5 food groups in your weight loss diet. Fruits, vegetables, whole grains, dairy, and lean proteins all play an important role in your long-term health.
  • Eat a primarily plant-based diet. My recommendation is to substitute plant proteins for at least half of your high-fat animal proteins. And this study reminds us that soy protein foods are a convenient and effective way to achieve this goal.
  • Eat a diet high in natural fibers. Including fruits, vegetables, whole grains, beans, nuts, seeds, and soy foods in your diet is the best way to achieve this goal.
  • Substitute healthy fats (monounsaturated and omega-3 fats) for unhealthy fats (saturated and trans fats) in your diet. And this study reminds us that it is hard to get enough omega-3s in your diet without an omega-3 supplement.
  • Reduce the amount of added sugar, especially fructose, from your diet. That is best achieved by eliminating sodas, sweets, and highly processed foods from the diet. I should add that fructose in fruits and some healthy foods is not a problem. For more information on that topic, I refer you to a previous “Health Tips” article .
  • Finally, I would like to remind you of the obvious. No diet, no matter how healthy, will help you lose weight unless you cut back on calories. Fad diets achieve that by restricting the foods you can eat. In the case of a healthy diet, the best way to do it is to cut back on portion sizes and choose foods with low caloric density.

I should touch briefly on the third major conclusion of this study, namely that the “high-nutrient quality diet” was not more effective than the “low-nutrient-quality” diet for people who were insulin resistant. In one sense, this was not news. Previous studies have suggested that insulin-resistant individuals have more difficulty losing weight. That’s the bad news.

However, there was a silver lining to this finding as well:

  • Only around half of the overweight, abdominally obese adults in this study were highly insulin resistant.
    • That means there is a ~50% chance that you will lose more weight on a healthy diet.
  • Because both diets restricted calories by 25%, insulin-resistant individuals lost weight on both diets.
    • That means you can lose weight on any diet that successfully reduces your caloric intake. That’s the good news.
    • However, my recommendation would still be to choose a high-nutrient quality diet that is designed to reduce caloric intake, because that diet is more likely to be healthy long term.

The Bottom Line 

A recent study asked, “Can healthy eating help you lose weight?” This study was a randomized controlled study, the gold standard of clinical studies. The participants were randomly assigned to:

  • A high-nutrient quality diet that restricted calories by 25%.
  • A low-nutrient-quality diet that restricted calories by 25%.
  • Continue with their habitual diet.

These were not healthy and unhealthy diets in the traditional sense.

  • Both were whole food diets.
  • Both included fruits, vegetables, low-fat dairy, and lean meats.
  • Both restricted calories by 25%.

The diets were designed so that the “high-nutrient quality” diet had significantly more plant protein (in the form of soy protein), fiber, healthy fats (monounsaturated and omega-3 fats), and significantly less fructose and other simple sugars than the “low-nutrient-quality” diet.

At the end of 12 weeks:

  • Participants on the high-nutrient quality diet lost 33% more weight than participants on the low-nutrient-quality diet (18.5 pounds compared to 13.9 pounds).

When the investigators measured cardiovascular risk factors at the end of 12 weeks:

  • The reduction in total serum cholesterol was 2.5-fold greater and the reduction in triglycerides was 2-fold greater in the high-nutrient quality diet group than in the low-nutrient-quality diet group.
  • The reduction in systolic blood pressure was 2-fold greater and the reduction in diastolic blood pressure was 1.67-fold greater in the high-nutrient quality diet group than in the low-nutrient-quality diet group.

The authors concluded, “Our results demonstrate that the nutrient composition of an energy-restricted diet is of great importance for improvements of metabolic health in an overweight, middle-aged population. A high-nutrient quality energy-restricted diet enriched with soy protein, fiber, monounsaturated fats, omega-3 fats, and reduced in fructose provided additional health benefits over a low-nutrient quality energy-restricted diet, resulting in greater weight loss…and promoting an antiatherogenic blood lipid profile.”

In short, participants in this study lost more weight and had a better improvement in risk factors for heart disease on a high-nutrient-quality diet than on a low-nutrient-quality diet. Put another way, healthy eating helped them lose weight and improved their health.

For more details on this study, what this study means for you, and my 7 recommendations for a healthy weight loss diet, 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.

Can Diet Protect Your Mind?

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Which Diet Is Best?

Author: Dr. Stephen Chaney 

can diet prevent alzheimer'sAlzheimer’s is a scary disease. There is so much to look forward to in our golden years. We want to enjoy the fruits of our years of hard work. We want to enjoy our grandkids and perhaps even our great grandkids. More importantly, we want to be able to pass on our accumulated experiences and wisdom to future generations.

Alzheimer’s and other forms of dementia have the potential to rob us of everything that makes life worth living. What is the use of having a healthy body, family, and fortune if we can’t even recognize the people around us?

Alzheimer’s and other forms of dementia don’t happen overnight. The first symptoms of cognitive decline are things like forgetting names, where you left things, what you did last week. For most people it just keeps getting worse.

Can diet protect your mind? Recent studies have given us a ray of hope. For example, several meta-analyses have shown that adherence to the Mediterranean diet was associated with a 25-48% lower risk of cognitive decline and dementia.

However, there were several limitations to the studies included in these meta-analyses. For example:

  • For most of the studies the diet was assessed only at the beginning of the study. We have no idea whether the participants followed the same diet throughout the study. This means, we cannot answer questions like:
    • What is the effect of long-term adherence to a healthy diet?
    • Can you reduce your risk of cognitive decline if you switch from an unhealthy diet to a healthy diet?
  • These studies focused primarily on the Mediterranean diet. This leaves the question:
    • What about other healthy diets? Is there something unique about the Mediterranean diet, or do other healthy diets also reduce the risk of cognitive decline?

This study (C Yuan et al, American Journal of Clinical Nutrition, 115: 232-243, 2022) was designed to answer those questions.

How Was The Study Done?

clinical studyThe investigators utilized data from The Nurse’s Health Study. They followed 49,493 female nurses for 30 years from 1984 to 2014. The average age of the nurses in 1984 was 48 years, and none of them had symptoms of cognitive decline at the beginning of the study.

The nurse’s diets were analyzed in 1984, 1986, and every 4 years afterwards until 2006. Diets were not analyzed during the last 8 years of the study to eliminate something called “reverse causation”. Simply put, the investigators were trying to eliminate the possibility that participants in the study might change their diet because they were starting to notice symptoms of cognitive decline.

The data from the dietary analyses were used to calculate adherence to 3 different healthy diets:

  • The Mediterranean diet.
  • The DASH diet. The DASH diet was designed to reduce the risk of high blood pressure. But you can think of it as an Americanized version of the Mediterranean diet.
  • The diet recommended by the USDA. Adherence to this diet is evaluated by something called the Alternative Healthy Eating Index or AHEI.

Adherence to each diet was calculated by giving a positive score to foods that were recommended for the diet and a negative score for foods that were not recommended for the diet. For more details, read the article.

In 2012 and 2014 the nurses were asked to fill out questionnaires self-assessing the early stages of cognitive decline. They were asked if they had more trouble than usual:

  • Remembering recent events or remembering a short list of items like a grocery list (measuring memory).
  • Understanding things, following spoken instructions, following a group conversation, or following a plot in a TV program (measuring executive function).
  • Remembering things from one second to the next (measuring attention).
  • Finding ways around familiar streets (measuring visuospatial skills).

The extent of cognitive decline was calculated based on the number of yes answers to these questions.

Can Diet Protect Your Mind?

Vegan FoodsHere is what the investigators found when they analyzed the data:

At the beginning of the study in 1984 there were 49,493 female nurses with an average age of 48. None of them had symptoms of cognitive decline.

  • By 2012-2014 (average age = 76-78) 46.9% of them had cognitive decline and 12.3% of them had severe cognitive decline.

Using the data on dietary intake and the rating systems specific to each of the diets studied, the investigators divided the participants into thirds based on their adherence to each diet. The investigators then used these data to answer two important questions that no previous study had answered:

#1: What is the effect of long-term adherence to a healthy diet? To answer this question the investigators averaged the dietary data obtained every 4 years between 1984 and 2006 to obtain cumulative average scores for adherence to each diet. When the investigators compared participants with the highest adherence to various healthy diets for 30 years to participants with the lowest adherence to those diets, the risk of developing severe cognitive decline was decreased by:

  • 40% for the Mediterranean diet.
  • 32% for the DASH diet.
  • 20% for the USDA-recommended healthy diet (as measured by the AHEI score).

#2: Can you reduce your risk of cognitive decline if you switch from an unhealthy diet to a healthy diet? To answer this question, the investigators looked at participants who started with the lowest adherence to each diet and improved to the highest adherence by the end of the study. This study showed that improving from an unhealthy diet to a healthy diet over 30 years decreased the risk of developing severe cognitive decline by:

  • 20% for the Mediterranean diet.
  • 25% for the DASH diet.

There were a few other significant observations from this study.

  • The inverse association between healthy diets and risk of cognitive decline was greater for nurses who had high blood pressure.
    • This is an important finding because high blood pressure increases the risk of cognitive decline.
  • The inverse association between healthy diets and risk of cognitive decline was also greater for nurses who did not have the APOE-ɛ4 gene.
    • This illustrates the interaction of diet and genetics. The APOE-ɛ4 gene increases the risk of cognitive decline. Healthy diets reduced the risk of cognitive decline in nurse with the APOE-ɛ4 gene but not to the same extent as for nurses without the gene.

This study did not investigate the mechanism by which healthy diets reduced the risk of cognitive decline, but the investigators speculated it might be because these diets:

  • Were anti-inflammatory.
  • Supported the growth of healthy gut bacteria.

The investigators concluded, “Our findings support the beneficial roles of long-term adherence to the [Mediterranean, DASH, and USDA] dietary patterns for maintaining cognition in women…Further, among those with initially relatively low-quality diets, improvement in diet quality was associated with a lower likelihood of developing severe cognitive decline. These findings indicate that improvements in diet quality in midlife and later may have a role in maintenance of cognitive function among women.”

Which Diet Is Best?

Mediterranean Diet FoodsIn a sense this is a trick question. That’s because this study did not put the participants on different diets. It simply analyzed the diets the women were eating in different ways. And while the algorithms they were using were diet-specific, there was tremendous overlap between them. For more specifics on the algorithms used to estimate adherence to each diet, read the article.

That is why the investigators concluded that all three diets they analyzed reduced the risk of cognitive decline rather than highlighting a specific diet. However, based on this and numerous previous studies the evidence is strongest for the Mediterranean and DASH diets.

And I would be remiss if I didn’t also mention the MIND diet. While it was not included in this study, the MIND diet:

  • Was specifically designed to reduce cognitive decline.
  • Can be thought of as a combination of the Mediterranean and DASH diets.
  • Includes data from studies on the mind-benefits of individual foods. For example, it recommends berries rather than all fruits.

The MIND diet has not been as extensively studied as the Mediterranean and DASH diets, but there is some evidence that it may be more effective at reducing cognitive decline than either the Mediterranean or DASH diets alone.

Which Foods Are Best?

AwardThe authors of this study felt it was more important to focus on foods rather than diets. This is a better approach because we eat foods rather than diets. With that in mind they analyzed their data to identify the foods that prevented cognitive decline and the foods increased cognitive decline. This is what they found:

  • Fruits, fruit juices, vegetables, fish, nuts, legumes, low-fat dairy, and omega-3 fatty acids (fish oil) reduced the risk of cognitive decline.
  • Red and processed meats, omega-6 fatty acids (most vegetable oils), and trans fats increased the risk of cognitive decline.

While this study did not specifically look at the effect of processed foods on cognitive decline, diets high in the mind-healthy foods listed above are generally low in sodas, sweets, and highly processed foods.

What Does This Study Mean For You?

Question MarkThe question, “Can diet protect your mind”, is not a new one. Several previous studies have suggested that healthy diets reduce the risk of cognitive decline, but this study breaks new ground. It shows for the first time that:

  • Long-term adherence to a healthy diet can reduce your risk of cognitive decline by up to 40%.
    • This was a 30-year study, so we aren’t talking about “diet” in the traditional sense. We aren’t talking about short-term diets to drop a few pounds. We are talking about a life-long change in the foods we eat.
  • If you currently have a lousy diet, it’s not too late to change. You can reduce your risk of cognitive decline by switching to a healthier diet.
    • This is perhaps the best news to come out of this study.

Based on current evidence, the best diets for protecting against cognitive decline appear to be the Mediterranean, DASH, and MIND diets.

And if you don’t like restrictive diets, my advice is to:

  • Eat more fruits, fruit juices, vegetables, fish, nuts, legumes, low-fat dairy, and omega-3 fatty acids (fish oil).
  • Eat less red and processed meats, omega-6 fatty acids (most vegetable oils), and trans fats.
  • Eat more plant foods and less animal foods.
  • Eat more whole foods and less sodas, sweets, and processed foods.

And, of course, a holistic approach is always best. Other lifestyle factors that help reduce your risk of cognitive decline include:

  • Regular exercise.
  • Weight control.
  • Socialization.
  • Memory training (mental exercises).

The Bottom Line 

Alzheimer’s is a scary disease. What is the use of having a healthy body, family, and fortune if we can’t even recognize the people around us?

A recent study looked at the effect of diet on cognitive decline in women. The study started with middle-aged women (average age = 48) and followed them for 30 years. The investigators then used these data to answer two important questions that no previous study had answered:

#1: What is the effect of long-term adherence to a healthy diet? When the investigators compared participants with the highest adherence to various healthy diets for 30 years to participants with the lowest adherence to those diets, the risk of developing severe cognitive decline was decreased by:

  • 40% for the Mediterranean diet.
  • 32% for the DASH diet.
  • 20% for the USDA recommendations for a healthy diet.

#2: Can you reduce your risk of cognitive decline if you switch from an unhealthy diet to a healthy diet? This study showed that improving from an unhealthy diet to a healthy diet over 30 years decreased the risk of developing severe cognitive decline by:

  • 20% for the Mediterranean diet.
  • 25% for the DASH diet.

The investigators concluded, “Our findings support the beneficial roles of long-term adherence to the [Mediterranean, DASH, and USDA] dietary patterns for maintaining cognition in women…Further, among those with initially relatively low-quality diets, improvement in diet quality was associated with a lower likelihood of developing severe cognitive decline. These findings indicate that improvements in diet quality in midlife and later may have a role in maintenance of cognitive function among women.”

For more details on the study, which diets, and which foods are best for protecting your mind, and what this study 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.

What Is The Truth About Low Carb Diets?

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Why Is The Cochrane Collaboration The Gold Standard?

Author: Dr. Stephen Chaney 

low carb dietAtkins, South Beach, Whole30, Low Carb, high Fat, Low Carb Paleo, and Keto. Low carb diets come in many forms. But they have these general characteristics:

  • They restrict carbohydrate intake to <40% of calories.
  • They restrict grains, cereals, legumes, and other carbohydrate foods such as dairy, fruits, and some vegetables.
  • They replace these foods with foods higher in fat and protein such as meats, eggs, cheese, butter, cream, and oils.
  • When recommended for weight loss, they generally restrict calories.

What about the science? Dr. Strangelove and his friends tell you that low carb diets are better for weight loss, blood sugar control, and are more heart healthy than other diets. But these claims are controversial.

Why is that? I have discussed this in previous issues of “Health Tips From The Professor”. Here is the short version.

  • Most studies on the benefits of low carb diets compare them with the typical American diet.
    • The typical American diet is high in fat, sugar and refined flour, and highly processed foods. Anything is better than the typical American diet.
  • Most low carb diets are whole food diets.
    • Any time you replace sodas and highly processed foods with whole foods you will lose weight and improve your health.
  • Most low carb diets are highly structured. There are rules for which foods to avoid, which foods to eat, and often additional rules to follow.
    • Any highly structured diet causes you to focus on what you eat. When you do that, you lose weight. When you lose weight, your health parameters improve.
    • As I have noted before, short term weight loss and improvement in health parameters are virtually identical for the very low carb keto diet and the very low-fat vegan diet.

With all this uncertainty you are probably wondering, “What is the truth about low carb diets?”

A recent study by the Cochrane Collaboration (CE Naude et al, Cochrane Database of Systematic Reviews, 28 January 2022) was designed to answer this question.

The Cochrane Collaboration is considered the gold standard of evidence-based medicine. To help you understand why this is, I will repeat a summary of how the Cochrane Collaboration approaches clinical studies that I shared two weeks ago.

Why Is The Cochrane Collaboration The Gold Standard?

ghost bustersWho you gonna call? It’s not Ghostbusters. It’s not Dr. Strangelove’s health blog. It’s a group called the Cochrane Collaboration.

The Cochrane Collaboration consists of 30,000 volunteer scientific experts from across the globe whose sole mission is to analyze the scientific literature and publish reviews of health claims so that health professionals, patients, and policy makers can make evidence-based choices about health interventions.

In one sense, Cochrane reviews are what is called a “meta-analysis”, in which data from numerous studies are grouped together so that a statistically significant conclusion can be reached. However, Cochrane Collaboration reviews differ from most meta-analyses found in the scientific literature in a very significant way.

Many published meta-analyses simply report “statistically significant” conclusions. However, statistics can be misleading. As Mark Twain said: “There are lies. There are damn lies. And then there are statistics”.

The Cochrane Collaboration also reports statistically significant conclusions from their meta-analyses. However, they carefully consider the quality of each individual study in their analysis. They look at possible sources of bias. They look at the design and size of the studies. Finally, they ask whether the conclusions are consistent from one study to the next. They clearly define the quality of evidence that backs up each of their conclusions as follows:

  • High-quality evidence. Further research is unlikely to change their conclusion. This is generally reserved for conclusions backed by multiple high-quality studies that have all come to the same conclusion. These are the recommendations that are most often adopted into medical practice.
  • Moderate-quality evidence. This conclusion is very likely to be true, but further research could have an impact on it.
  • Low-quality evidence. Further research is needed and could alter the conclusion. They are not judging whether the conclusion is true or false. They are simply saying more research is needed to reach a definite conclusion.

This is why their reviews are considered the gold standard of evidence-based medicine. If you are of a certain age, you may remember that TV commercial “When EF Hutton talks, people listen.” It is the same with the Cochrane Collaboration. When they talk, health professionals listen.

How Was The Study Done?

Clinical StudyThe authors of this Cochrane Collaboration Report included 61 published clinical trials that randomized participants into two groups.

  • The first group was put on a low carbohydrate diet (carbohydrates = <40% of calories).
  • The second group was put on a “normal carbohydrate” diet (carbohydrates = 45-65% of calories, as recommended by the USDA and most health authorities).
    • The normal carbohydrate diet was matched with the low carbohydrate diet in terms of caloric restriction.
    • Both diets were designed by dietitians and were generally whole food diets.

The participants in these studies:

  • Were middle-aged.
  • Were overweight or obese.
  • Did not have diagnosed heart disease or cancer.
  • May have diagnosed type-2 diabetes. Some studies selected participants that had diagnosed type 2 diabetes. Other studies excluded those patients.

The studies were of 3 types:

  • Short-term: Participants in these studies followed their assigned diets for 3 to <12 months.
  • Long-term: Participants in these studies followed their assigned diets for >12 to 24 months.
  • Short-term with maintenance: Participants in these studies followed their assigned diets for 3 months followed by a 9-month maintenance phase.

What Is The Truth About Low Carb Diets?

The TruthAll the studies included in the Cochrane Collaboration’s meta-analysis randomly assigned overweight participants to a low carbohydrate diet (carbohydrates = <40% of calories) or to a “normal carbohydrate” diet (carbohydrates = 45-65% of calories) with the same degree of caloric restriction.

If low carb diets have any benefit in terms of weight loss, improving blood sugar control, or reducing heart disease risk, these are the kind of studies that are required to validate that claim.

This is what the Cochrane Collaboration’s meta-analysis showed.

When they analyzed studies done with overweight participants without type 2 diabetes:

  • Weight loss was not significantly different between low carb and normal carb diets in short-term studies (3 to <12 months), long-term studies (>12 to 24 months), and short-term studies followed by a 9-month maintenance period.
  • There was also no significant difference in the effect of low carb and normal carb diets on the reduction in diastolic blood pressure and LDL cholesterol.

Since diabetics have trouble controlling blood sugar, you might expect that type 2 diabetics would respond better to low carb diets. However, when they analyzed studies done with overweight participants who had type 2 diabetes:

  • Weight loss was also not significantly different on low carb and normal carb diets.
  • There was no significant difference in the effect of low carb and normal carb diets on the reduction in diastolic blood pressure, LDL cholesterol, and hemoglobin A1c, a measure of blood sugar control.

Of course, the reason Cochrane Collaboration analyses are so valuable is they also analyze the strength of the studies that were included in their analysis.

You may remember in my article two weeks ago, I reported on the Cochrane Collaboration’s report supporting the claim that omega-3 supplementation reduces pre-term births. In that report they said that the studies included in their analysis were high quality. Therefore, they said their report was definitive and no more studies were needed.

This analysis was different. The authors of this Cochrane Collaboration report said that the published studies on this topic were of moderate quality. This means their conclusion is very likely to be true, but further research could have an impact on it.

What Does This Study Mean For You?

confusionIf you are a bit confused by the preceding section, I understand. That was a lot of information to take in. Let me give you the Cliff Notes version.

In short, this Cochrane Collaboration Report concluded:

  • Low carb diets (<40% of calories from carbohydrates) are no better than diets with normal carbohydrate content (45-65% of calories from carbohydrates) with respect to weight loss, reduction in heart disease risk factors, and blood sugar control. Dr. Strangelove has been misleading you again.
  • This finding is equally true for people with and without type 2 diabetes. This calls into question the claim that people with type 2 diabetes will do better on a low carb diet.
  • The published studies on this topic were of moderate quality. This means their conclusion is very likely to be true, but further research could have an impact on it.

If you are thinking this study can’t be true because low carb diets work for you, that is because you are comparing low carb diets to your customary diet, probably the typical American diet.

  • Remember that any whole food diet that eliminates sodas and processed foods and restricts the foods you eat will cause you to lose weight. Whole food keto and vegan diets work equally well short-term compared to the typical American diet.
  • And any diet that allows you to lose weight improves heart health parameters and blood sugar control.

If you are thinking about the blogs, books, and videos you have seen extolling the virtues of low carb diets, remember that the Dr. Strangeloves of the world only select studies comparing low carb diets to the typical American diet to support their claims.

  • The studies included in this Cochrane Collaboration report randomly assigned participants to the low carb and normal carb diets and followed them for 3 to 24 months.
    • Both diets were whole food diets designed by dietitians.
    • Both diets reduced caloric intake to the same extent.

What about the claims that low carb diets are better for your long-term health? There are very few studies on that topic. Here are two:

  • At the 6.4-year mark a recent study reported that the group with the lowest carbohydrate intake had an increased risk of premature death – 32% for overall mortality, 50% for cardiovascular mortality, 51% for cerebrovascular mortality, and 36% for cancer mortality. I will analyze this study in a future issue of “Health Tips From The Professor”.
  • At the 20-year mark a series of studies reported that:
    • Women consuming a meat-based low carb diet for 20 years gained just as much weight and had just as high risk of heart disease and diabetes as women consuming a high carbohydrate, low fat diet.
    • However, women consuming a plant-based low carb diet for 20 years gained less weight and had reduced risk of developing heart disease and diabetes as women consuming a high carbohydrate, low fat diet.

My recommendation is to avoid low-carb diets. They have no short-term benefits when compared to a healthy diet that does not eliminate food groups. And they may be bad for you in the long run. Your best bet is a whole food diet that includes all food groups but eliminates sodas, sweets, and processed foods.

However, if you are committed to a low carb diet, my recommendation is to choose the low-carb version of the Mediterranean diet. It is likely to be healthy long term.

The Bottom Line 

The Cochrane Collaboration, the gold standard of evidence-based medicine, recently issued a report that evaluated the claims made for low carb diets.

All the studies analyzed in the Cochrane Collaboration’s report randomly assigned overweight participants to a low carbohydrate diet (carbohydrates = <40% of calories) or to a “normal carbohydrate” diet (carbohydrates = 45-65% of calories) with the same degree of caloric restriction.

If low carb diets have any benefit in terms of weight loss, improving blood sugar control, or reducing heart disease risk, these are the kind of studies that are required to validate that claim.

The Cochrane Collaboration Report concluded:

  • Low carb diets (<40% of calories from carbohydrates) are no better than diets with normal carbohydrate content (45-65% of calories from carbohydrates) with respect to weight loss, reduction in heart disease risk factors, and blood sugar control.
  • This is equally true for people with and without type 2 diabetes.
  • The published studies on this topic were of moderate quality. This means their conclusion is very likely to be true, but further research could have an impact on it.

My recommendation is to avoid low carb diets. They have no short-term benefits when compared to a healthy diet that does not eliminate food groups. And they may be bad for you in the long run. Your best bet is a whole food diet that includes all food groups but eliminates sodas, sweets, and processed foods.

However, if you are committed to a low carb diet, my recommendation is to choose the low carb version of the Mediterranean diet. It is likely to be healthy long term.

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.

Does Red Meat Cause Frailty In Older Women?

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Which Proteins Are Best?

Author: Dr. Stephen Chaney

Fatty SteakThe ads from the meat lobby say, “Red meat does a body good”. Are the ads true?

If we consider the health consequences of regularly eating red meat, the answer appears to be a clear, “No”. Multiple studies have shown a link between red meat consumption and:

  • Coronary heart disease.
  • Stroke
  • Type 2 diabetes.
  • Colon cancer, prostate cancer, and breast cancer.

And, if we consider the environmental consequences of red meat production, the answer also appears to be, “No”. I have discussed this in a recent issue of “Health Tips From the Professor”.

But what about muscle mass and strength? Red meat is a rich source of protein, and we associate meat consumption with an increase in muscle mass. Surely, red meat consumption must help us build muscle mass and strength when we are young and preserve muscle mass and strength as we age.

This is why the recent headlines claiming that red meat consumption increases the risk of frailty in older women were so confusing. I, like you, found those headlines to be counterintuitive. So, I have investigated the study (EA Struijk et al, Journal of Cachexia, Sarcopenia and Muscle, 13: 210-219, 2022) behind the headlines. Here is what I found.

How Was The Study Done?

Clinical StudyThis study utilized data acquired from the Nurses’ Health Study (NHS). The NHS began in 1976 with 121,700 female nurses aged 30 to 55. This study followed 85,871 nurses in the NHS once they reached age 60 for an average of 14 years.

Dietary intake was assessed using a food frequency questionnaire that was administered to all participants in the study every four years between 1980 and 2010. The long-term intake of red meat and other protein sources was based on a cumulative average of all available diet questionnaires for each participant.

The participants also filled out a Medical Outcomes Short Report every four years between 1992 and 2014. Data from this survey was used to calculate something called the FRAIL scale, which includes the following frailty criteria:

  • Fatigue
  • Low muscle strength.
  • Reduced aerobic capacity.
  • Having ≥5 of the following chronic diseases:
    • Cancer
    • High blood pressure
    • Type 2 diabetes
    • Angina
    • Myocardial infarction (heart attack)
    • Congestive heart failure
    • Asthma
    • COPD (chronic obstructive pulmonary disease)
    • Arthritis
    • Parkinson’s disease
    • Kidney disease
    • Depression
  • Greater than ≥5% weight loss in two consecutive assessments.

Frailty was defined as having met 3 or more criteria in the FRAIL scale. The study looked at the effect of habitual consumption of red meat or other protein sources on the development of frailty during the 14-year follow-up period.

Does Red Meat Cause Frailty In Older Women?

The investigators separated the participants into 5 quintiles based on total red meat consumption, unprocessed red meat construction, or processed red meat consumption. The range of intakes was as follows.

Total red meat: 0.4 servings per day to 1.8 servings per day.

Unprocessed red meat: 0.3 servings per day to 1.3 servings per day.

Processed red meat: 0.04 servings per day to 0.6 servings per day.

Clearly none of the women in this study were consuming either vegan or keto diets. As might be expected from a cross-section of the American public, there was a fairly narrow range of daily meat consumption.

Here are the results of the study:

  • Each serving per day of total red meat increased frailty by 13%.
  • Each serving per day of unprocessed red meat increased frailty by 8%.
  • Each serving per day of processed red meat increased frailty by 26%.
  • When each component of the frailty index was examined individually, all of them were positively associated with red meat consumption except for weight loss.

This was perhaps the most unexpected finding of the study. Not only did red meat consumption increased the risk of chronic diseases in these women, which would be expected from many previous studies. But red meat consumption also made these women more tired, weaker, and shorter of breath.

The authors concluded, “Habitual consumption of any type of red meat was associated with a higher risk of frailty.”

Which Proteins Are Best?

Red Meat Vs White MeatThe investigators then asked if replacing one serving/day of red meat with other protein sources was associated with a significantly lower risk of frailty. Here is what they found:

  • Replacing one serving per day of unprocessed red meat with a serving of:
    • Fish reduced frailty risk by 22%.
    • Nuts reduced frailty risk by 14%.
  • Replacing one serving per day of processed red meat with a serving of:
    • Fish reduced frailty risk by 33%
    • Nuts reduced frailty risk by 26%
    • Low-fat dairy reduced frailty risk by 16%
    • Legumes reduced frailty risk by 13%.

The authors concluded, “Replacing red meat with another source of protein including fish, nuts, legumes, and low-fat dairy may be encouraged to reduce the risk of developing frailty syndrome. These findings are in line with dietary guidelines promoting diets that emphasize plant-based sources of protein.” [I would note that fish and low-fat dairy are hardly plant-based protein sources.]

What Does This Study Mean For You?

Questioning WomanI am not yet ready to jump on the “eating red meat causes frailty” bandwagon. This is a very large, well-designed study, but it is a single study. It needs to be replicated by future studies.

And, as a biochemist, I am skeptical about any study that does not offer a clear metabolic rationale for the results. As I said earlier, increased protein intake is usually associated with an increase in muscle mass when we are young and a preservation of muscle mass as we age. There is no obvious metabolic explanation for why an increase in red meat consumption in older women would cause a decrease in muscle mass and other symptoms of frailty.

On the other hand, there are plenty of well documented reasons for decreasing red meat intake. Consumption of red meat is bad for our health and bad for the health of the planet as I have discussed in an earlier issue of “Health Tips From the Professor”. And substituting other protein sources, especially plant proteins, is better for our health and the health of our planet.

Finally, we also need to consider the possibility that this study is correct and that future studies will confirm these findings. Stranger things have happened.

As we age, we begin to lose muscle mass, a process called sarcopenia. Increased protein intake and resistance exercise can help slow this process. While I am not ready to say that red meat causes decreased muscle mass, I do think this study should make us think about which protein sources we use to prevent sarcopenia. At the very least we should not use age-related muscle loss as an excuse to increase our red meat intake. That might just be counterproductive.

The Bottom Line

A recent study looked at the effect of red meat consumption on frailty in older women. It came to the unexpected conclusion that:

  • Each serving per day of total red meat increased frailty by 13%.
  • Each serving per day of unprocessed red meat increased frailty by 8%.
  • Each serving per day of processed red meat increased frailty by 26%.
  • The increase in frailty could be reduced by replacing one serving/day of red meat with a serving of fish, nuts, low-fat dairy, or legumes.

I am not yet ready to jump on the “eating red meat causes frailty” bandwagon. This is a very large, well-designed study, but it is a single study. It needs to be replicated by future studies. And, as a biochemist, I am skeptical about any study that does not offer a clear metabolic rationale for the results.

On the other hand, there are plenty of well documented reasons for decreasing red meat intake. Consumption of red meat is bad for our health and for the health of the planet.

Finally, we also need to consider the possibility that this study is correct and that future studies will confirm these findings. Stranger things have happened.

As we age, we begin to lose muscle mass, a process called sarcopenia. Increased protein intake and resistance exercise can help slow this process. This study should make us think about which protein sources we use to prevent sarcopenia. At the very least we should not use age-related muscle loss as an excuse to increase our red meat intake. That might just be counterproductive.

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.

Eating For A Healthy Planet

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Can Diet Affect The Health Of Our Planet?

Author: Dr. Stephen Chaney

Earth DayEarth Day has come and gone. You have recommitted to saving the planet. You plan to recycle, conserve energy, and turn in your gas guzzler for an energy efficient car. But what about your diet? Is your diet destroying the planet?

This is not a new question, but a recent commission of international scientists has conducted a comprehensive study into our diet and its effect on our health and our environment. Their report (W. Willet et al, The Lancet, 393, issue 10170, 447-492, 2019) serves as a dire warning of what will happen if we don’t change our ways. I touched on this report briefly in a previous issue of “Health Tips From The Professor”, but this topic is important enough that it deserves an issue all its own.

The commission carefully evaluated diet and food production methods and asked three questions:

  • Are they good for us?
  • Are they good for the planet?
  • Are they sustainable? Will they be able to meet the needs of the projected population of 10 billion people in 2050 without degrading our environment.

The commission described the typical American diet as a “lose-lose-lose diet”. It is bad for our health. It is bad for the planet. And it is not sustainable.

In its place they carefully designed their version of a primarily plant-based diet they called a “win-win-win diet”. It is good for our health. It is good for the planet. And it is sustainable.

In their publication they refer to their diet as the “universal healthy reference diet” (What else would you expect from a committee?). However, it has become popularly known as the “Planetary Diet”.

I have spoken before about the importance of a primarily plant-based diet for our health. In that context it is a personal choice. It is optional.

However, this report is a wake-up call. It puts a primarily plant-based diet in an entirely different context. It is essential for the survival of our planet. It is no longer optional.

If you care about our environment…If you care about saving our planet, there is no other choice.

How Was The Study Done?

The publication (W. Willet et al, The Lancet, 393, issue 10170, 447-492, 2019) was the report of the EAT-Lancet Commission on Healthy Diets from Sustainable Food Systems. This Commission convened 30 of the top experts from across the globe to prepare a science-based evaluation of the effect of diet on both health and sustainable food production through the year 2050. The Commission included world class experts on healthy diets, agricultural methods, climate change, and earth sciences. The Commission reviewed 356 published studies in preparing their report.

Can Diet Affect The Health Of Our Planet?

Factory FarmWhen they looked at the effect of food production on the environment, the Commission concluded:

  • “Strong evidence indicates that food production is among the largest drivers of global environmental change.” Specifically, the commission reported:
    • Agriculture occupies 40% of global land (58% of that is for pasture use).
    • Food production is responsible for 30% of global greenhouse gas emissions and 70% of freshwater use.
    • Conversion of natural ecosystems to croplands and pastures is the largest factor causing species to be threatened with extinction. Specifically, 80% of extinction threats to mammals and bird species are due to agricultural practices.
    • Overuse and misuse of nitrogen and phosphorous in fertilizers causes eutrophication. In case you are wondering, eutrophication is defined as the process by which a body of water becomes enriched in dissolved nutrients (such as phosphates from commercial fertilizer) that stimulate the growth of algae and other aquatic plant life, usually resulting in the depletion of dissolved oxygen. This creates dead zones in lakes and coastal regions where fish and other marine organisms cannot survive.
    • About 60% of world fish stocks are fully fished and more than 30% are overfished. Because of this, catch by global marine fisheries has been declining since 1996.
  • “Reaching the Paris Agreement of limiting global warming…is not possible by only decarbonizing the global energy systems. Transformation to healthy diets from sustainable food systems is essential to achieving the Paris Agreement.”
  • The world’s population is expected to increase to 10 billion by 2050. The current system of food production is unsustainable.

healthy vs Unhealthy ChoicesWhen they looked at the effect of the foods we eat on the environment, the Commission concluded:

  • Beef and lamb are the biggest contributors to greenhouse gas emissions and land use.
    • The concern about land use is obvious because of the large amount of pastureland required to raise cattle and sheep.
    • The concern about greenhouse gas emissions is because cattle and sheep are ruminants. They not only breathe out CO2, but they also release methane into the atmosphere from fermentation in their rumens of the food they eat. Methane is a potent greenhouse gas, and it persists in the atmosphere 25 times longer than CO2.

The single most important thing we can do as individuals to reduce greenhouse gas emissions is to eat less beef and lamb. [Note: grass fed cattle produce more greenhouse gas emissions than cattle raised on corn because they require 3 years to bring to market rather than 2 years.] 

    • In contrast, plant crops reduce greenhouse gas emissions by removing CO2 from the atmosphere.
  • In terms of energy use beef, lamb, pork, chicken, dairy, and eggs all require much more energy to produce than any of the plant foods.
  • In terms of eutrophication of our lakes and oceans, beef, lamb, and pork, all cause much more eutrophication than any plant food. Dairy and eggs cause more eutrophication than any plant food except fruits.

Eating For A Healthier Planet

Planetary DietIn the words of the Commission: “[The Planetary Diet] largely consists of vegetables, fruits, whole grains, legumes, nuts, and unsaturated oils. It includes a low to moderate amount of seafood, poultry, and eggs. It includes no or a very low amount of red meat, processed meat, sugar, refined grains, and starchy vegetables.”

When described in that fashion it sounds very much like other healthy diets such as semi-vegetarian, Mediterranean, DASH, and Flexitarian. However, what truly distinguishes it from the other diets is the restrictions placed on the non-plant portion of the diet to make it both environmentally friendly and sustainable. Here is a more detailed description of the diet:

  • It starts with a vegetarian diet. Vegetables, fruits, beans, nuts, soy foods, and whole grains are the foundation of the diet.
  • It allows the option of adding one serving of dairy a day (It turns out that cows produce much less greenhouse emissions per serving of dairy than per serving of beef. That’s because cows take several years to mature before they can be converted to meat, and they are emitting greenhouse gases the entire time).
  • It allows the option of adding one 3 oz serving of fish or poultry or one egg per day.
  • It allows the option of swapping seafood, poultry, or egg for a 3 oz serving of red meat no more than once a week. If you want a 12 oz steak, that would be no more than once a month.

This is obviously very different from the way most Americans currently eat. According to the Commission:

  • “This would require greater than 50% reduction in consumption of unhealthy foods, such as red meat and sugar, and greater than 100% increase in the consumption of healthy foods, such as nuts, fruits, vegetables, and legumes”.
  • “In addition to the benefits for the environment, “dietary changes from current diets to healthy diets are likely to substantially benefit human health, averting about 10.8-11.6 million deaths per year globally.”

What Else Did The Commission Recommend?

In addition to changes in our diets, the Commission also recommended several changes in the way food is produced. Here are a few of them.

  • Reduce greenhouse gas emissions from the fuel used to transport food to market.
  • Reduce food losses and waste by at least 50%.
  • Make radical improvements in the efficiency of fertilizer and water use. In terms of fertilizer, the change would be two-fold:
    • In developed countries, reduce fertilizer use and put in place systems to capture runoff and recycle the phosphorous.
    • In third world countries, make fertilizer more available so that crop yields can be increased, something the Commission refer to as eliminating the “yield gap” between third world and developed countries.
  • Stop the expansion of new agricultural land use into natural ecosystems and put in place policies aimed at restoring and re-foresting degraded land.
  • Manage the world’s oceans effectively to ensure that fish stocks are used responsibly and global aquaculture (fish farm) production is expanded sustainability.

What we can do: While most of these are government level policies, we can contribute to the first three by reducing personal food waste and purchasing organic produce locally whenever possible.

What Does This Mean For You?

confusionIf you are a vegan, you are probably asking why the Commission did not recommend a completely plant-based diet. The answer is that a vegan diet is perfect for the health of our planet. However, the Commission wanted to make a diet that was as consumer friendly as possible and still meet their goals of a healthy, environmentally friendly, and sustainable diet.

If you are eating a typical American diet or one of the fad diets that encourage meat consumption, you are probably wondering how you can ever make such drastic changes to your diet. The answer is “one step at a time”. If you have read the Forward to my books “Slaying The Food Myths” or “Slaying the Supplement Myths”, you know that my wife and I did not change our diet overnight. Our diet evolved to something very close to the Planetary Diet over a period of years.

The Commission also purposely designed the Planetary Diet so that you “never have to say never” to your favorite foods. Three ounces of red meat a week does not sound like much, but it allows you a juicy steak once a month.

Sometimes you just need to develop a new mindset. As I shared in my books, my father prided himself on grilling the perfect steak. I love steaks, but I decided to set a few parameters. I don’t waste my red meat calories on anything besides filet mignon at a fine restaurant. It must be a special occasion, and someone else must be buying. That limits it to 2-3 times a year. I still get to enjoy good steak, and I stay well within the parameters of the Planetary diet.

Develop your strategy for enjoying some of your favorite foods within the parameters of the Planetary Diet and have fun with it.

The Bottom Line

Is your diet destroying the planet? This is not a new question, but a recent commission of international scientists has conducted a comprehensive study into our diet and its effect on our health and our environment. Their report serves as a dire warning of what will happen to us and our planet if we don’t change our ways.

The Commission carefully evaluated diet and food production methods and asked three questions:

  • Are they good for us?
  • Are they good for the planet?
  • Are they sustainable? Will they be able to meet the needs of the projected population of 10 billion people in 2050 without degrading our environment.

The Commission described the typical American diet as a “lose-lose-lose diet”. It is bad for our health. It is bad for the planet. And it is not sustainable.

In its place they carefully designed their version of a primarily plant-based diet they called a “win-win-win diet”. It is good for our health. It is good for the planet. And, it is sustainable.

In their publication they refer to their diet as the “universal healthy reference diet” (What else would you expect from a committee?). However, it has become popularly known as the “Planetary Diet”.

The Planetary Diet is similar to other healthy diets such as semi-vegetarian, Mediterranean, DASH, and Flexitarian. However, what truly distinguishes it from the other diets is the restrictions placed on the non-plant portion of the diet to make it both environmentally friendly and sustainable (for details, read the article above).

I have spoken before about the importance of a primarily plant-based diet for our health. In that context it is a personal choice. It is optional.

However, this report is a wake-up call. It puts a primarily plant-based diet in an entirely different context. It is essential for the survival of our planet. It is no longer optional.

If you care about global warming…If you care about saving our planet, there is no other choice.

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.

Can Diet Add Years To Your Life?

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Which Foods Have The Biggest Effect On Longevity? 

Author: Dr. Stephen Chaney

Fountain Of YouthEveryone over 50 is searching for the elusive “Fountain Of Youth”.

  • We want to look younger.
  • We want to feel younger.
  • We want the energy we had in our 20s.
  • We want to be rid of the diseases of aging.

The list goes on!

But how do we do that? Pills and potions abound that claim to reverse the aging process. Most just reverse your wallet.

  • Should we train for marathons or bodybuilding contests?
  • Should we meditate or do yoga to relieve stress?
  • Should we get serious about losing weight?
  • Should we get more sleep?
  • Is there some miracle diet that can slow the aging process?

All the above probably slow the aging process, but the evidence is best for the effect of diet on aging. Several recent meta-analyses have looked at the effect of diet on the risk of premature deaths. In this issue of “Health Tips From the Professor” I review a study (LT Fadnes et al, PLoS Medicine, February 8, 2022) that combines the best of these meta-analyses into a single database and provides a provocative insight into the effect of diet on longevity.

How Was This Study Done?

Clinical StudyThis study combined data from recent meta-analyses looking at the impact of various food groups on the risk of premature deaths with the Global Burden of Disease Study which provides population-level estimates of life years lost due to dietary risk factors.

The authors then developed a new algorithm that allowed them to estimate how different diets affect sex- and age-specific life expectancy.

They divided the population into three different diet categories based on their intake of whole grains, vegetables, fruits, nuts, legumes, fish, eggs, dairy, refined grains, red meat, processed meat, white meat, sugar-sweetened beverages, and added plant oils. The diet categories were:

  • Typical Western Diet (TW). This diet was based on average consumption data from the United States and Europe. This was their baseline.
  • Optimal diet (OD). This diet is similar to a vegan or semi-vegetarian diet. However, it was not a purely vegan diet nor a purely semi-vegetarian diet. Instead, it represented the best diet people in this study were consuming.
  • Feasibility diet (FA). This diet recognizes that few people are willing to make the kind of changes required to attain an optimal diet. It is halfway between the Typical Western Diet and the Optimal Diet.

To help you understand these diets based on the foods the study participants were eating, here are the comparisons in terms of daily servings:

Food TW Diet FA Diet OD Diet
Whole grains 1.5 servings 4.3 servings 7 servings
Vegetables 3 servings 4 servings 5 servings
Fruits 2.5 servings 3.75 servings 5 servings
Nuts 0 serving* 0.5 serving* 1 serving*
Legumes 0 serving** 0.5 serving** 1 serving**
Fish 0.25 serving 0.5 serving 1 serving
Eggs 1 egg 0.75 egg 0.5 egg
Dairy 1.5 servings 1.25 servings 1 serving
Refined grains 3 servings 2 servings 1 serving
Red meat 1 serving 0.5 serving 0 serving
Processed meat 2 servings 1 serving 0 serving
White meat 0.75 serving 0.6 serving 0 serving
Sugar-sweetened beverages 17 oz 8.5 oz 0 oz
Added plant oils 2 tsp 2 tsp 2 tsp

*1 serving = 1 handful of nuts

**1 serving = 1 cup of beans, lentils, or peas

Using their algorithm, the authors asked what the effect on longevity would be if people changed from a typical western diet to one of the other diets at age 20, 60, or 80 and maintained the new diet for at least 10 years. The 10-year requirement is based on previous studies showing that it takes around 10 years for dietary changes to affect the major killer diseases like heart disease, cancer, or diabetes.

Finally, the authors improved the accuracy of their estimates of the effect of diet on longevity by taking into account the quality of each study included in their analysis. I will discuss the importance of this below.

Can Diet Add Years To Your Life?

The results were impressive.

The authors estimated that if people in the United States were to change from a typical western diet to an “optimal diet” and maintain it for at least 10 years,

…starting at age 20, men would live 13 years longer and women would live 10.7 years longer.

…starting at age 60, men would live 8.8 years longer and women would live 8 years longer.

…starting at age 80, both men and women would live 3.4 years longer.

But what if you weren’t a vegan purist? What if you only made half the changes you would need to make to optimize your diet? The news was still good.

The authors estimated that people in the United States were to change from a typical western diet to a “feasibility diet” and maintain it for at least 10 years,

…starting at age 20, men would live 7.3 years longer and women would live 6.2 years longer.

…starting at age 60, men would live 4.8 years longer and women would live 4.5 years longer.

…starting at age 80, both men and women would live ~2 years longer.

The authors concluded, “A sustained dietary change may give substantial health gains for people of all ages for both optimized and feasible [diet] changes. [These health gains] could translate into an increase in life expectancy of more than 10 years. Gains are predicted to be larger the earlier the dietary changes are initiated in life.”

Which Foods Have The Biggest Effect On Longevity?

The algorithm the authors developed also allowed them to look at which foods have the biggest effect on longevity. The authors estimated when changing from a typical western diet to an optimal diet, the greatest gains in longevity were made by eating:

  • More legumes, whole grains, and nuts, and…
  • Less red and processed meat.

The authors concluded, “An increase in the intake of legumes, whole grains, and nuts, and a reduction in the intake of red meat and processed meats, contributed most to these gains [in longevity].”

However, this conclusion needs to be interpreted with caution. We also need to recognize that an “optimal diet” was defined as the best diet people in this study were eating. In addition, the effect of different foods on longevity depends on:

  • The quality of the individual studies with that food, and…
  • The difference in consumption of that food in going from a western diet to an optimal diet.

For example:

  • Legumes, whole grains, nuts, red & processed meat made the list because the quality of data was high and the difference in consumption between the typical western diet and optimal diet was significant.
  • The quality of data for an effect of fruits and vegetables was also high. For example, one major study concluded that consuming 10 servings a day of fruits and vegetables a day reduces premature death by 31% compared to consumption of less than 1 serving a day. However, the difference in consumption of fruits and vegetables between the western and optimal diets in this study was small, so fruits and vegetables didn’t make the list.
  • Eggs and white meat didn’t make the list because the quality of data was low for those foods. Simply put,  that means that there was a large variation in effect of those foods on longevity between studies.
  • Other foods didn’t make the list because the quality of data was only moderate and/or the difference in intake was small.

So, the best way to interpret this these data is:

  • This study suggests that consuming more legumes, whole grains, and nuts and less red & processed meats has a significant beneficial effect on health and longevity.
  • Consuming more fruits and vegetables is likely to have a significant benefit on health and longevity, but you would need to consume more than people did in this study to achieve these benefits. In the words of the authors, “Fruits and vegetables also have a positive health impact, but, for these food groups, the intake in a typical Western diet is closer to the optimal intake than for the other food groups.”
  • Other foods may impact health and longevity, but the data in this study are not good enough to be confident of an effect.

What Does This Study Mean For You?

This study is the best of many studies showing the benefit of a more plant-based diet on health and longevity. It particularly encouraging because it shows:

  • You can achieve significant benefit by switching to a more plant-based diet late in life. You get the biggest “bang for your buck” if you switch at age 20. But even making the switch at age 60 or 80 was beneficial.
  • You don’t need to be a “vegan purist”. While the biggest benefits were seen for people who came close to achieving a vegan or semi-vegetarian diet, people who only made half those changes saw significant benefits.

As I said above, this is a very strong study. However, the underlying data come from association studies, which can have confounding variables that influence the results.holistic approach

For example, people who eat more plant-based diets tend to weigh less and exercise more. And both of those variables can influence longevity. Each study attempted to statistically correct for those variables, but they still might have a slight influence on the results.

However, I don’t see that as a problem because, in my view, a holistic approach is always best. As illustrated on the right, we should be seeking a lifestyle that includes a healthy diet, weight control, and exercise.

As for supplementation, both the vegan and semi-vegetarian diets tend to leave out whole food groups. Unless you are married to a dietitian, that means your diet is likely to be missing important nutrients.

The Bottom Line

A recent study asked whether changing from the typical western diet to a healthier, more plant-based diet could influence longevity. The results were very encouraging. The study showed that:

  • Changing to a healthier diet could add up to a decade to your lifespan.
  • The improvement in lifespan was greatest for those whose diets approached a vegan or semi-vegetarian diet, but a significant improvement in lifespan was seen for people who made only half those dietary improvements.
  • The improvement in lifespan was greatest for those who switched to a healthier diet in their 20’s, but significant improvements in lifespan were seen for people who didn’t change their diet until their 60’s or 80’s.

In terms of the foods that have the biggest effect on longevity.

  • This study suggests that consuming more legumes, whole grains, and nuts and less red & processed meats has a significant beneficial effect on health and longevity.
  • Consuming more fruits and vegetables is likely to have a significant benefit on health and longevity, but you would need to consume more than people did in this study to achieve those benefits.
  • Other foods may impact health and longevity, but the data in this study are not good enough to be confident of an effect.

The authors concluded, “A sustained dietary change may give substantial health gains for people of all ages for both optimized and feasible [diet] changes. [These health gains] could translate into an increase in life expectancy of more than 10 years. Gains are predicted to be larger the earlier the dietary changes are initiated in life.

An increase in the intake of legumes, whole grains, and nuts, and a reduction in the intake of red meat and processed meats, contributed most to these gains. Fruits and vegetables also have a positive health impact, but, for these food groups, the intake in a typical Western diet is closer to the optimal intake than for the other food groups.”

For more details about this 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.

Eating Of The Green

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Why Is Eating Green Good For Your Heart? 

Author: Dr. Stephen Chaney

You may be one of the millions of Americans who celebrated St. Patrick’s Day a couple of weeks ago. If so, you may have sung the famous Irish folk song “The Wearing of the Green”. If you are Irish, that song has special meaning for you. However, when I hear that song, I think of “Eating of the Green.”

And when I think of eating green, I don’t mean that everything we eat should be green. I am thinking of whole fruits and vegetables in a variety of colors. We have known for years that fruits and vegetables are good for our health. Consumption of fruits and vegetables is associated a lower risk of high blood pressure, heart disease, cancer, inflammatory diseases, and much more.

For today’s health tip, I am going to focus on heart health and an unexpected explanation for how fruits and vegetables reduce our risk of heart disease.

Why Is Eating Green Good For Your Heart?

health benefits of beetroot juiceWe have assumed that whole fruits and vegetables lower our risk of heart disease because they are low in saturated fats and provide heart-healthy nutrients, phytonutrients, and fiber. All of that is true. But could there be more?

Recent research has suggested that the nitrates found naturally in fruits and vegetables may also play a role in protecting our hearts. Here is what recent research shows:

  • The nitrates from fruits and vegetables are converted to nitrite by bacteria in our mouth and intestines.
    • Fruits and vegetables account for 80% of the nitrate in our diet. The rest comes from a variety of sources including the nitrate added as a preservative to processed meats.
    • Although all fruits and vegetables contain nitrates, the best sources are green leafy vegetables and beetroot. [Beet greens are delicious and also a good source of nitrate, but beetroot is the part of the beet we usually consume.]
  • Nitrite is absorbed from our intestine and converted to nitric oxide by a variety of enzymes in our tissues.
  • Both reactions require antioxidants like vitamin C, which are also found in fruits and vegetables.

Nitric oxide has several heart healthy benefits. For example:

  • It helps reduce inflammation in the lining of blood vessels. Inflammation stimulates atherosclerosis, blood clot formation, and is associated with an increased risk of heart disease.
  • It relaxes the smooth muscle cells that surround our blood vessels. This makes the blood vessels more flexible and helps reduce blood pressure.
  • It prevents smooth muscle cells from proliferating, which prevents them from invading and constricting our arteries. This, in turn, has the potential to reduce the risk of atherosclerosis.
  • It prevents platelet aggregation. This, in turn, has the potential to reduce the risk of heart attack and stroke due to blood clots that block the flow of blood to our heart or brain.

It is well established that nitrates from fruits and vegetables reduce blood pressure. More importantly, they can help slow the gradual increase in blood pressure as we age.

However, few studies have asked whether this reduction in blood pressure translates into improved cardiovascular outcomes. This study (CP Bondonno et al, European Journal of Epidemiology, 36: 813-825, 2021) was designed to answer that question.

How Was This Study Done?

Clinical StudyThis study made use of data from the Danish Diet, Cancer, and Health Program. That program enrolled 53,150 participants from Copenhagen and Aarhus between 1993 and 1997 and followed them for an average of 21 years. None of the participants had a diagnosis of cancer or heart disease at the beginning of the study.

Other characteristics of the participants at the time they were enrolled in the study were:

  • 46% male
  • Average age = 56
  • BMI = 26 (>20% overweight)
  • Average systolic blood pressure = 140 mg Hg
  • Average diastolic blood pressure = 84 mg Hg

At the beginning of the study, participants filled out a 192-item food frequency questionnaire that assessed their average intake of various food and beverage items over the previous 12 months. The vegetable nitrate content of their diets was analyzed using a comprehensive database of the nitrate content of 178 vegetables. For those vegetables not consumed raw, the nitrate content was reduced by 50% to account for the nitrate loss during cooking.

Blood pressure was measured at the beginning of the study. Data on the incidence (first diagnosis) of heart disease during the study was obtained from the Danish National Patient Registry. Data were collected on diagnosis of the following heart health parameters:

  • Cardiovascular disease (all diseases of the circulatory system).
  • Ischemic heart disease (lack of sufficient blood flow to the heart). The symptoms of ischemic heart disease range from angina to myocardial infarction (heart attack).
  • Ischemic stroke (lack of sufficient blood flow to the brain).
  • Hemorrhagic stroke (bleeding in brain).
  • Heart failure.
  • Peripheral artery disease (lack of sufficient blood flow to the extremities).

Is Nitrate From Vegetables Good For Your Heart?

strong heartIntake of nitrate from vegetables ranged from 18 mg/day (<1/3 serving of nitrate-rich vegetables per day) to 168 mg (almost 3 servings of nitrate-rich vegetables per day). The participants were grouped into quintiles based on their vegetable nitrate intake. When the group with the highest vegetable nitrate intake was compared to the group with the lowest vegetable nitrate intake:

  • Systolic blood pressure was reduced by 2.58 mg Hg.
  • Diastolic blood pressure was reduced by 1.38 mg Hg.
  • Risk of cardiovascular disease was reduced by 14%.
  • Risk of ischemic heart disease (angina and heart attack) was reduced by 13%.
  • Risk of ischemic stroke (stroke caused by lack of blood flow to the brain) was reduced by 14%.
  • Risk of heart failure was reduced by 17%.
  • Risk of peripheral artery disease was reduced by 31%.
  • Risk of hemorrhagic stroke (bleeding in the brain) was not significantly reduced.

Two other observations were of interest:

  • Blood pressure and risk of peripheral artery disease decreased with increasing vegetable nitrate intake in a relatively linear fashion. However, the other parameters of heart disease plateaued at a modest intake of vegetable nitrate intake (around one cup of nitrate-rich vegetables per day). This suggests that as little as one serving of nitrate-rich vegetables a day is enough to provide some heart health benefits.
  • Only about 21.9% of the improvement in heart health could be explained by the decrease in blood pressure. This is not surprising when you consider the other beneficial effects of nitric oxide described above.

The authors concluded, “Consumption of at least ~60 mg/day of vegetable nitrate (~ one serving of green leafy vegetables or beets) may mitigate risk of cardiovascular disease.”

Are Nitrates Good For You Or Bad For You?

questionsYou are probably thinking, “Wait a minute. I thought nitrates and nitrites were supposed to be bad for me. Which is it? Are nitrates good for me or bad for me?”

It turns out that nitrates and nitrites are kind of like Dr. Jekyll and Mr. Hyde. They can be either good or bad. It depends on the food they are in and your overall diet.

Remember the beginning of this article when I said that the conversion of nitrates to nitric oxide depended on the presence of antioxidants? Vegetables are great sources of antioxidants. So, when we get our nitrate from vegetables, most of it is converted to nitric oxide. And, as I discussed above, nitric oxide is good for us.

However, when nitrates and nitrites are added to processed meats as a preservative, the story is much different. Processed meats have zero antioxidants. And the protein in the meats is broken down to amino acids in our intestine. The amino acids combine with nitrate to form nitrosamines, which are cancer-causing chemicals. Nitrosamines are bad for us.

Of course, we don’t eat individual foods by themselves. We eat them in the context of a meal. If you eat small amounts of nitrate-preserved processed meats in the context of a meal with antioxidant-rich fruits and vegetables, some of the nitrate will be converted to nitric oxide rather than nitrosamines. The processed meat won’t be as bad for you.

Eating Of The Green

spinachYour mother was right. You should eat your fruits and vegetables!

  • The USDA recommends at least 3 servings of vegetables and 2 servings of fruit a day.
  • Based on this study, at least one of those servings should be nitrate-rich vegetables like green leafy vegetables and beets.
  • If you don’t like any of those, radishes, turnips, watercress, Bok choy, Chinese cabbage, kohlrabi, chicory leaf, onion, and fresh garlic are also excellent sources of nitrate.
  • The good news is that you may not need to eat green leafy vegetables and beets with every meal. If this study is correct, one serving per day may have heart health benefits. That means you can enjoy a wide variety of fresh fruits and vegetables as you try to meet the USDA recommendations.

Finally, if you don’t like any of those foods, you may be asking, “Can’t I just take a nitrate supplement?”

  • For blood pressure, there are dozens of clinical trials, and the answer seems to be yes – especially when the nitrate comes from vegetable sources and the supplement also contains an antioxidant like vitamin C.
  • For heart health benefits, the answer is likely to be yes, but clinical trials to confirm that would take decades. Double blind, placebo-controlled trials of that duration are not feasible, so we will never know for sure.
  • Moreover, you would not be getting all the other health benefits of a diet full of fresh fruits and vegetables. Supplementation has its benefits, but it is not meant to replace a healthy diet.

The Bottom Line

We have known for years that fruits and vegetables are good for our hearts. We have assumed that was because whole fruits and vegetables are low in saturated fats and provide heart-healthy nutrients, phytonutrients, and fiber. But could there be more?

It is well established that nitrates from fruits and vegetables reduce blood pressure. More importantly, they can help slow the gradual increase in blood pressure as we age.

However, few studies have asked whether this reduction in blood pressure translates into improved cardiovascular outcomes. A recent study was designed to answer that question.

When the study compared people with the highest vegetable nitrate intake to people with the lowest vegetable nitrate intake:

  • Blood pressure was significantly reduced.
  • The risk of cardiovascular disease was reduced by 14%.
  • Risk of ischemic heart disease (angina and heart attack) was reduced by 13%.
  • Risk of ischemic stroke (stroke caused by lack of blood flow to the brain) was reduced by 14%.
  • Risk of heart failure was reduced by 17%.
  • Risk of peripheral artery disease was reduced by 31%.
  • Blood pressure and risk of peripheral artery disease decreased with increasing vegetable nitrate intake in a relatively linear fashion.
  • However, the other parameters of heart disease plateaued at a modest intake of vegetable nitrate intake (around one cup of nitrate-rich vegetables per day). This suggests that as little as one serving of nitrate-rich vegetables a day is enough to provide some heart health benefits.

The authors concluded, “Consumption of at least ~60 mg/day of vegetable nitrate (~ one serving of green leafy vegetables or beets) may mitigate risk of cardiovascular disease.”

Of course, you may have heard that nitrates and nitrites are bad for you. I discuss that in the article above.

For more details about this 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.

Does Olive Oil Help You Live Longer?

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Which Fat Is Healthiest?

Author: Dr. Stephen Chaney

If you believe the headlines, olive oil is a superfood. It is often described as the star of the Mediterranean diet. It is referred to as the healthiest of dietary fats. Is this true, or is it hype?

Olive oil’s resume is impressive:

  • It is rich in monounsaturated fatty acids, which…
    • Are less susceptible to oxidation than polyunsaturated oils.
    • Make our arteries more flexible, which lowers blood pressure.
    • Lower LDL-cholesterol levels, which reduces the risk of heart disease.
  • Extra-virgin olive oil contains phytonutrients and tocopherols (various forms of vitamin E), which…
    • Have anti-inflammatory properties.
    • Improve insulin sensitivity and blood sugar control.
  • Olive oil consumption is also associated with healthier gut bacteria, but it is not clear whether this is due to olive oil or to the fact that a Mediterranean diet is also richer in fresh fruits, vegetables, and whole grains.

Several recent studies have shown that olive oil consumption is associated with a lower risk of heart disease. However, these studies were conducted in Mediterranean countries where the average intake of olive oil (3 tablespoons/day) is much greater than in the United States (0.3 tablespoons/day).

The current study (M Guasch-Ferré et al, Journal of the American College of Cardiology, 79: 101-112, 2022) was designed to test whether:

  • The amount of olive oil Americans consume decreases the risk of heart disease.
  • Whether olive oil consumption had benefits beyond a reduction in heart disease risk.

How Was This Study Done? 

Clinical StudyThis study combined data from 60,582 women enrolled in the Nurses’ Health Study and 31,801 men enrolled in the Health Professionals Follow-Up Study). The participants:

  • Were free of heart disease and diabetes at the start of the study.
  • Were 56 at the start of the study with an average BMI of 25.6 (Individuals with BMIs in the 25-30 range are considered overweight, so they were at the lowest end of the overweight range).

The Nurses’ Health Study and Health Professional Follow-Up Study are both association studies, meaning they looked at the association between olive oil consumption and health outcomes. They cannot directly prove cause and effect. However, they are very strong association studies because:

  • Every 2 years, participants filled out a questionnaire that updated information on their body weight, smoking status, physical activity, medications, multivitamin use, and physician-diagnosed diseases.
  • Every 4 years, participants filled out a comprehensive food frequency questionnaire.
  • In other words, this study did not just rely on the participant’s lifestyle, dietary intake, and health at the beginning of the study, as so many association studies do. It tracked how each of these variables changed over time.

The participants were followed for an average of 28 years and their average olive oil intake over those 28 years was correlated with all-cause mortality and mortality due to specific diseases.

  • Deaths were identified from state vital statistics, the National Death index, reports by next of kin, or reports by postal authorities.
  • Causes of death were determined by physician review of medical records, medical reports, autopsy reports, or death certificates.

Does Olive Oil Help You Live Longer?

During the 28 years of this study:

  • Olive oil consumption in the United States increased from an average of ~1/3 teaspoon/day to ~1/3 tablespoon/day.
  • Margarine consumption decreased from 12 g/day to ~4 g/day.
  • The consumption of all other fats and oils remained about the same.

As I mentioned above, olive oil consumption was averaged over the life of the study for each individual. When the investigators compared people consuming the highest amount of olive oil (>0.5 tablespoon/day) with people consuming the least olive oil (0 to 1 teaspoon/day):

  • Mortality from all causes was decreased by 35% for the group consuming the most olive oil.

However, the group consuming the most olive oil also was more physically active, had a healthier diet, and consumed more fruits and vegetables than the group who consumed the least olive oil.

  • After correcting for all those factors, mortality from all causes was decreased by 19% for the group consuming the most olive oil.

The authors concluded, “We found that greater consumption of olive oil was associated with lower risk of total…mortality… Our results support current dietary recommendations to increase the intake of olive oil…to improve overall health and longevity.” (I will fill in the blanks in this statement once I have covered other aspects of this study)

The authors also said, “Of note, our study showed that benefits of olive oil can be observed even when consumed in lower amounts than in Mediterranean countries.”

Are There Other Benefits From Olive Oil Consumption?

Mediterranean dietThe study didn’t stop there. The investigators also looked at the effect of olive oil consumption on the major killer diseases in the United States and other developed countries. When they compared the effect of olive oil consumption on cause-specific mortality, they found that the group who consumed the most olive oil reduced their risk of dying from:

  • Cardiovascular disease by 19%.
  • Cancer by 17%
  • Respiratory disease by 18%.
  • Neurodegenerative disease (cognitive decline and Alzheimer’s disease) by 29%.
    • The reduction in neurodegenerative disease was much greater for women (34% decrease) than for men (19% decrease).

With this information I can fill in one of the blanks in the author’s conclusions: “We found that greater consumption of olive oil was associated with lower risk of total and cause-specific mortality… Our results support current dietary recommendations to increase the intake of olive oil…to improve overall health and longevity.”

Which Fats Are Healthiest?

Good Fat vs Bad FatThe sample size was large enough and the dietary information complete enough for the investigators to also estimate the effect of substituting olive oil for other dietary fats and oils.

They found that every ¾ tablespoon of olive oil substituted for an equivalent amount of:

  • Margarine decreased total mortality by 13%.
  • Butter decreased total mortality by 14%.
  • Mayonnaise deceased total mortality by 19%
  • Dairy fat decreased total mortality by 13%.
    • The same beneficial effects of substituting olive oil for other fats were seen for cause-specific mortality (cardiovascular disease, cancer, respiratory disease, and neurodegenerative disease).
    • There was a linear dose-response. This means that substituting twice as much olive oil for other dietary fats doubled the beneficial effects on total and cause-specific mortality.
  • However, substituting olive oil for polyunsaturated vegetable oils had no effect on total and cause-specific mortality.

Now I can fill in the remaining blanks in the author’s conclusion: “We found that greater consumption of olive oil was associated with lower risk of total and cause-specific mortality. Replacing other types of fat, such as margarine, butter, mayonnaise, and dairy fat, with olive oil was also associated with a lower risk of mortality. Our results support current dietary recommendations to increase the intake of olive oil and other unsaturated vegetable oils in place of other fats to improve overall health and longevity.”

What Does This Study Mean For Us?

ConfusionAs I said above, this is an association study, and association studies do not prove cause and effect. However:

1) This is a very strong association study because:

    • It is a very large study (92,383 participants).
    • It followed the participants over a long time (28 years).
    • It utilized a very precise dietary analysis.
    • Most importantly, it tracked the participant’s lifestyle, dietary intake, and health at regular intervals throughout the study. Most association studies only measure these variables at the beginning of the study. They have no idea how they change over time.

2) This study is consistent with several previous studies showing that olive oil consumption decreases the risk of dying from heart disease.

3) This study draws on its large population size and precise dietary analysis to strengthen and extend the previous studies. For example:

    • The study showed that increased olive oil consumption also reduced total mortality and mortality due to cancer, respiratory disease, and neurodegenerative disease.
    • The study measured the effect of substituting olive oil for other common dietary fats.
    • The study showed that increased olive oil consumption in the context of the American diet was beneficial.

I should point out that the headlines you have seen about this study may be misleading.

  • While the headlines may have depicted olive oil as a superfood, this study did not find evidence that olive oil was more beneficial than other unsaturated vegetable oils. Again, this is consistent with many previous studies showing that substituting vegetable oils for other dietary fats reduces the risk of multiple diseases.
  • The headlines focused on the benefits of increasing olive oil consumption. However, they neglected the data showing that increasing olive oil (and other vegetable oils) was even more beneficial (35% reduction in total mortality) in the context of a healthy diet – one with increased intake of fruits, vegetables, whole grains, nuts, legumes, and long-chain omega-3s and decreased intake of red & processed meats, sodium, and trans fats.

So, my recommendation is to follow a whole food, primarily plant-based diet and substitute extra-virgin olive oil and cold pressed vegetable oils for some of the animal fats in your diet.

Some vegan enthusiasts recommend a very low-fat whole food plant-based diet. They point to studies showing that such diets can actually reverse atherosclerosis. However:

  • Those studies are very small.
  • The overall diet used in those studies is a very healthy plant-based diet.
  • The studies did not include a control group following the same diet with olive oil or other vegetable oils added to it, so there is no comparison of a healthy vegan diet with and without vegetable oils.

If you have read my book, “Slaying the Food Myths”, you know that my recommendations encompass a variety of whole food, primarily plant-based diets ranging all the way from very-low fat vegan diets to Mediterranean and DASH diets. Choose the one that best fits your food preferences and the one you will be most able to stick with long term. You will be healthier, and you may live longer.

The Bottom Line

A recent study looked at the effect of olive oil consumption on the risk dying from all causes and from heart disease, cancer, respiratory disease, and neurodegenerative diseases. When the study compared people consuming the highest amount of olive oil (>0.5 tablespoon/day) with people consuming the least olive oil (0 to 1 teaspoon/day):

  • Mortality from all causes was decreased by 19% for the group consuming the most olive oil.

They also found that the group who consumed the most olive oil reduced their risk of dying from:

  • Cardiovascular disease by 19%.
  • Cancer by 17%
  • Respiratory disease by 18%.
  • Neurodegenerative disease (cognitive decline and Alzheimer’s disease) by 29%.

They also found that every ¾ tablespoon of olive oil substituted for an equivalent amount of:

  • Margarine decreased total mortality by 13%.
  • Butter decreased total mortality by 14%.
  • Mayonnaise deceased total mortality by 19%
  • Dairy fat decreased total mortality by 13%.
  • However, substituting olive oil for polyunsaturated vegetable oils had no effect on total and cause-specific mortality.

The authors concluded, “We found that greater consumption of olive oil was associated with lower risk of total and cause-specific mortality. Replacing other types of fat, such as margarine, butter, mayonnaise, and dairy fat, with olive oil was also associated with a lower risk of mortality. Our results support current dietary recommendations to increase the intake of olive oil and other unsaturated vegetable oils in place of other fats to improve overall health and longevity.”

For more details and a summary of what this study 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.

Which Diets Are Best In 2022?

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Which Diet Should You Choose?

Author: Dr. Stephen Chaney

Emoticon-BadMany of you started 2022 with goals of losing weight and/or improving your health. In many cases, that involved choosing a new diet. That was only a month 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 2022”. For the full report, click on this link.

How Was This Report Created?

Expert PanelUS News & World Report recruited panel of 27 nationally recognized experts in diet, nutrition, obesity, food psychology, diabetes, and heart disease to review the 40 most popular diets.  The panel is not the same each year. Some experts are rotated off the panel, and others are added. The experts rate 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 2022?

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. The Mediterranean diet has been ranked #1 for 5 consecutive years.

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

#5: The TLC Diet (This diet was designed by the NIH to promote heart health.)

The Bottom 5: 

#36: Whole 30 Diet (A whole food, restrictive diet, designed for a 30-day jump start to weight loss. It was not designed for long-term use).

#37: Modified Keto Diet (A slightly less restrictive version of the Keto Diet).

#38: Keto Diet (A high protein, high fat, very low carb diet designed to achieve ketosis).

#39: Dukan Diet (High protein, low carb, low fat diet).

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

Best Weight-Loss Diets

The Top 5: Weight Loss

#1: Flexitarian Diet

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

#3: Vegan Diet (A diet that only allows plant foods).

#4: Mayo Clinic Diet (A diet designed to establish lifelong healthy eating habits).

#5: Ornish Diet (A whole food, semi-vegetarian diet designed to promote heart health).

The Bottom 5: 

#36: Fertility Diet (A diet designed to improve fertility, but the experts were skeptical that it would increase your chances of becoming pregnant)

#37: Whole 30 Diet

#38: Alkaline Diet (A diet designed to make your blood more alkaline, but the experts were skeptical about that claim)

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

#40: GAPS Diet

Best Diabetes Diets

The Top 5: 

#1: Mediterranean Diet

#2: Flexitarian Diet

#3: Vegan Diet

#4: Mayo Clinic Diet

#5: DASH Diet

The Bottom 5: 

#36: Alkaline Diet

#37: Dukan Diet

#38: GAPS Diet

#39: Sirtfood Diet (a very low calorie, fad diet that emphasizes plant foods rich in sirtuins)

#40: Whole 30 Diet

Best Heart-Healthy Diets 

strong heartThe Top 5: 

#1: Mediterranean Diet

#2: Ornish Diet

#3: DASH Diet

#4: Flexitarian Diet

#5: TLC Diet

#6: Vegan Diet

The Bottom 5: 

#36: Keto Diet

#37: AIP Diet

#38: Whole 30 Diet

#39: Modified Keto Diet

#40: Dukan Diet

Best Diets for Healthy Eating

The Top 5: 

#1: Mediterranean Diet

#2: DASH Diet

#3: Flexitarian Diet

#4: MIND Diet

#5: TLC Diet

The Bottom 5: 

#36: Raw Food Diet

#37: Atkins Diet

#38: Dukan Diet

#39: Modified Keto Diet

#40: Keto Diet 

Easiest Diets to Follow

The Top 5: Easy

#1: Mediterranean Diet

#2: Flexitarian Diet

#3: Fertility Diet

#4: MIND Diet

#5: DASH Diet

The Bottom 5: 

#36: Modified Keto Diet

#37: Keto Diet

#38: Whole 30 Diet

#39: GAPS Diet

#40: 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: Vegan Diet

The Bottom 5 

#36: Dr. Weil’s Anti-Inflammatory Diet

#37: The Fertility Diet

#38: AIP Diet

#39: Alkaline Diet

#40: Gaps Diet

Which Diets Are Best For Rapid Weight Loss?

Happy woman on scaleThere are 3 take-home lessons from the rapid weight loss category:

1) If you are looking for rapid weight loss, any whole food restrictive diet will do. The top 5 diets are very different. For example, the keto and vegan diets are polar opposites, yet they both are in the top 5 for rapid weight loss.

  • 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 vegan diet 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) 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.

3) Don’t pay too much attention to the bottom 5 diets. None of them were designed with weight loss in mind.

Which Diet Should You Choose?

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

1) 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.

2) 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.

3) Choose diets that are easy to follow. The less-restrictive primarily plant-based diets top this list – diets like Mediterranean, DASH, MIND, and flexitarian.

4) 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.

5) In case you were wondering, intermittent fasting ranked 26-30 and the Paleo diet ranked 26-33 on most of the list – not the worst diets, but a long way from the best. If you have a favorite diet I didn’t mention, check the US News website to find where it is ranked.

6) 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. These 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 2022”.

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.
  • 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.

Can Your Diet Cause You To Lose Your Mind?

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What Is A Mind-Healthy Lifestyle? 

Author: Dr. Stephen Chaney

Cognitive-DeclineMost of us look forward to our golden years – that mystical time when we will be free from the workday pressures and have more time to spend with friends and family doing the things we love.

But cognitive decline can cast a dark cloud over those expectations.

  • By the age of 65, 11% of adults suffer from some degree of cognitive impairment.
  • And by the age of 80 the percentage of adults suffering from cognitive impairment has increased to 26-30%, depending on which study you cite.

The results of cognitive decline can be devastating.

  • First you start to lose the cherished memories of a lifetime.
  • Then comes confusion and an inability to perform basic tasks and participate in your favorite activities.
  • Eventually you may reach a stage where you no longer recognize the ones you love.

In short, cognitive decline can rob you of everything that makes you you.

The causes of cognitive decline are complex, but recent studies have pointed to the role of chronic inflammation in cognitive decline. If that is true, it is a good news – bad news situation.

  • The bad news is:
    • Some increase in chronic inflammation appears to be an inevitable consequence of aging.
    • Chronic inflammation can be caused by certain diseases that are beyond our control.
    • Chronic inflammation can be triggered by viral or bacterial infections.
  • The good news is that chronic inflammation is also controlled by your diet and lifestyle. For example, as I said above, chronic inflammation is often triggered by a viral infection, but whether the inflammation is mild or severe is strongly influenced by diet and lifestyle.

In this issue of “Health Tips From the Professor” I share a study (S Charisis et al, Neurology, In Press, November 10, 2021) showing that diets high in inflammatory foods increase the risk of dementia. Then, I answer 3 important questions.

  • Can your diet cause you to lose your mind?
  • What is a mind-healthy diet?
  • What is a mind-healthy lifestyle?

How Was This Study Done?

Clinical StudyThe data for this study were taken from the first three years of the Hellenic Longitudinal Investigation of Aging and Diet (HELIAD), a study designed to look at the effect of diet on dementia and other neuropsychiatric conditions in the Greek population.

There were 1059 participants (40% male, average age = 75 at the beginning of the study) in this study. At the beginning of the study the participants completed a food frequency questionnaire administered by a trained dietitian. The foods were broken down into individual nutrients using the USDA Food Composition tables adapted for foods in the Greek diet.

The diet of each participant was then rated on a 15-point scale ranging from pro-inflammatory to anti-inflammatory based on something called the Diet Inflammation Index (DII).

Simply put, the DII is a validated assessment tool based on the effect of food nutrients on 6 inflammatory biomarkers found in the blood (IL-1β, IL-4, IL-6, IL-10, TNF-α, and CRP). Nutrients that decrease these markers are considered anti-inflammatory. Nutrients that increase these inflammatory biomarkers are considered pro-inflammatory.

For example, anti-inflammatory nutrients include:

  • Carotenoids and flavonoids (found in fruits and vegetables).
  • Omega-3 polyunsaturated fatty acids (found in cold-water fish, walnuts, flaxseeds, and chia seeds).
  • Monounsaturated fatty acids (found in olive, avocado, and peanut oils).
  • Fiber (found in minimally processed plant foods).
  • Antioxidants, most B vitamins, and vitamin D.
  • Magnesium and zinc.
  • Garlic, onions, most herbs & spices.

Pro-inflammatory nutrients include:

  • Refined carbohydrates.
  • Cholesterol.
  • Total fat.
  • Saturated fats.
  • Trans fats.

The participants were followed for 3 years, and all new diagnoses of dementia were recorded. The diagnoses were confirmed by a panel of neurologists and neuropsychologists.

Can Your Diet Cause You To Lose Your Mind?

Forgetful Old ManAs described above, the diet of each participant in the study was rated on a 15-point DII (Diet Inflammatory Index) scale ranging from pro-inflammatory to anti-inflammatory. The association of the DII score of the participant’s diets with the onset of dementia was evaluated in two ways.

  • Each one-point increase from an anti-inflammatory diet to a pro-inflammatory diet was associated with a 21% increase in the risk for dementia.
  • In other words, even small changes in your diet can have a significant impact on your risk of developing dementia.

The investigators then divided the participants into three equal-sized groups based on the DII score of their diets.

  • The group with the highest DII scores were 3 times more likely to develop dementia than the group with the lowest DII scores.
  • In other words, a major change in your diet can have a major effect on your risk of developing dementia.

The authors concluded, “In the present study, higher DII scores (indicating greater pro-inflammatory diet potential) were associated with an increased risk for incident dementia [newly diagnosed dementia]. These findings may avail the development of primary dementia strategies through tailored and precise dietary interventions.”

What Is A Mind-Healthy Diet?

Vegan FoodsThis and other studies show that an anti-inflammatory diet is good for the mind. It helps protect us from cognitive decline and dementia. But what does an anti-inflammatory diet look like?

One hint comes from analyzing the diets of participants in this study:

  • Those with the lowest DII scores (most-anti-inflammatory diets) consumed 20 servings of fruit, 19 servings of vegetables, 4 servings of beans or other legumes, and 11 servings of coffee or tea each week. That’s almost 3 servings of fruit and 3 servings of vegetables every day!
  • Those with the highest DII scores (most pro-inflammatory diets) consumed only half as many fruits, vegetables, and legumes.
  • In short, a diet rich in fruits, vegetables, and legumes is a good start.

I have described anti-inflammatory diets in more detail in a previous issue of “Health Tips From the Professor.” Let me summarize that article briefly.

Anti-inflammatory foods include:

  • Colorful fruits and vegetables.
  • Whole grains.
  • Beans and other legumes.
  • Nuts, olive oil, avocados, and other sources of monounsaturated fats.
  • Fatty fish and other sources of omega-3 fatty acids.
  • Herbs and spices.

Pro-inflammatory foods include:

  • Refined carbohydrates, sodas, and sugary foods.
  • Foods high in saturated fats including fatty and processed meats, butter, and high fat dairy products.
  • Foods high in trans fats.
  • French fries, fried chicken, and other fried foods.
  • Foods you are allergic or sensitive food. For example, gluten containing foods are pro-inflammatory only if you are sensitive to gluten.

If your goal is to reduce chronic inflammation and keep your mind sharp as a tack as you age, you should eat more anti-inflammatory foods and less pro-inflammatory foods.

Of course, we don’t just eat random foods, we follow dietary patterns. It should be apparent from what I have Mediterranean Diet Foodscovered above that whole food, primarily plant-based diets are anti-inflammatory. This is true for diets ranging from vegan through semi-vegetarian, to the Mediterranean, DASH, and MIND diets.

All these diets are anti-inflammatory and likely protect the brain from cognitive decline. However, the best evidence for brain protection is for the Mediterranean, DASH, and MIND diets.

  • The Mediterranean and DASH diets have been shown to prevent cognitive decline in multiple studies.
  • The MIND diet is a combination the Mediterranean and DASH diets that was specifically designed to prevent cognitive decline. It has been shown to cut the risk of developing Alzheimer’s disease in half.

What Is A Mind-Healthy Lifestyle?

Diet is just one aspect of a holistic approach for reducing cognitive decline as we age. Other important factors include:

  • Reduce excess body weight.
  • Exercise regularly.
  • Get adequate sleep.
  • Reduce and/or manage stress.
  • Eliminate smoking and reduce alcohol consumption.
  • Socialize with friends and family who support you. Numerous studies have shown that a strong support network reduces dementia risk in the elderly.
  • Keep your brain active. Work crossword puzzles. Learn new things. An active brain is forced to lay down new neural pathways.

The Bottom Line 

Recent studies have suggested that chronic inflammation increases the risk of cognitive decline and dementia as we age. Some causes of chronic inflammation are beyond our control, but others, such as diet, we can control.

Recently, a precise scoring system called the Diet Inflammatory Index (DII) has been developed. This scoring system allows studies to look at the correlation between the inflammatory potential of the diet and cognitive decline.

A recent study enrolled 1,000 participants with an average age of 75 in a 3-year study to determine the impact of diet on cognitive decline. The association of the DII score of the participant’s diets with the onset of dementia was evaluated in two ways.

  • Each one-point increase from an anti-inflammatory diet to a pro-inflammatory diet was associated with a 21% increase in the risk for dementia.
  • In other words, even small changes in your diet can have a significant impact on your risk of developing dementia.

The investigators then divided the participants into three equal-sized groups based on the DII score of their diets.

  • The group with the highest DII scores were 3 times more likely to develop dementia than the group with the lowest DII scores.
  • In other words, a major change in your diet can have a major effect on your risk of developing dementia.

The authors concluded, “In the present study, higher DII scores (indicating greater pro-inflammatory diet potential) were associated with an increased risk for incident dementia [newly diagnosed dementia]. These findings may avail the development of primary dementia strategies through tailored and precise dietary interventions.”

For more details and a description of mind-healthy diets and a mind-healthy lifestyle 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