Dr. Steve Chaney, Author at Health Tips From The Professor

Dairy Products and Heart Disease

January 29, 2019 by Dr. Steve Chaney

Will Eating Cheese Help You Live Longer?

Author: Dr. Stephen Chaney

A recent study is generating lots of headlines. Here are some examples:

Eating Dairy Foods Can Help Reduce Heart Disease Risk.
Fermented Dairy-Products May Protect Against Heart Attack.
Full-Fat Dairy May Actually Benefit Heart Health.
Eating Cheese Might Help You Live Longer.
Eating Cheese and Butter Every Day Linked To Living Longer.

My favorite headlines were the ones about cheese and longevity. For example, one headline read: “New Study Finds People That Eat Cheese Live Longer.” The article opened by saying “Sprinkle on another handful of mozzarella on your pizza, add an extra slice of American cheese on your burger, or grab a bite of sharp cheddar with your crackers. A new study published in The Lancet claims that eating cheese reduces your risk of stroke and cardiovascular disease. Now that’s something we like to hear.”

A lot of people must like to hear good news about cheese. The headlines about cheese making you live longer outnumbered all the other headlines by about 3 to 1.

In summary, the claims ranged from dairy foods in general to milk & fermented dairy foods, full-fat dairy foods, cheese, and cheese & butter. Let’s look at the study behind the claims to see which of these claims about dairy products and heart disease are true and which are wishful thinking.

How Was The Study Designed?

The study behind the headlines (M. Dehghan et al. The Lancet, 392: 2288-2297, 2018 ) was a very ambitious study called PURE (Prospective Urban Rural Epidemiology study). It was a large multinational study of 136,384 individuals aged 35-70 from 21 countries in five continents.

At the beginning of the study participants filled out a country-specific food frequency questionnaire. The data from this survey were broken down into total dairy foods, milk, yogurt, cheese, and butter. The data were also subdivided into low-fat and full-fat dairy foods.

The participants were followed for an average of 9.1 years. The outcomes measured at the end of the study were overall mortality, cardiovascular mortality, cardiovascular disease, heart attack, stroke and heart failure. The way these outcomes were measured was also country specific because the way these data are collected varies from country to country. [Note: There were some other outcomes measured, but for the sake of simplicity I have not included them in the discussion. Their omission does not change the discussion.]

Finally, in case you were wondering, this research was not funded by money from the dairy industry.

Dairy Products and Heart Disease Risk?

The results were interesting:

Higher intake of total dairy foods (>2 servings/day compared with no intake) was associated with a lower risk of overall mortality (17% less), cardiovascular mortality (23% less), cardiovascular disease (22% less) and stroke (34% less). No association of dairy consumption with heart attack or heart failure was seen.
Higher intake of milk (>1 serving per day compared with <0.5 servings/day) was associated with a lower risk cardiovascular disease (18% less).
Higher intake of yogurt (>1 serving/day compared with <0.5 servings/day) was associated with a lower risk of overall mortality (17% less) and cardiovascular disease (10% less).
No significant effect of cheese was observed for any of the outcomes measured.
Butter intake was low and was not associated with any of the outcomes measured.

The authors concluded: “We observed that higher dairy consumption was associated with lower risks of mortality and cardiovascular disease, particularly stroke. Our study suggests that consumption of dairy products should not be discouraged and perhaps should even be encouraged in low-income and middle-income countries where dairy consumption is less.”

Will Eating Cheese Help You Live Longer?

The claims you have been seeing about consumption of dairy foods in general, milk, and yoghurt reducing heart attack risk are supported by this study and several other recent studies.
I hate to disappoint you, but the claims about cheese and butter consumption reducing cardiovascular disease and extending lifespan are clearly wishful thinking. They are not supported by this study.

The discussion of full-fat versus low-fat dairy products is more complicated. You are undoubtedly aware that most current dietary guidelines recommend avoiding full-fat dairy foods in favor of low-fat alternatives. Studies like this have led some to question whether these dietary guidelines should be changed.

Interestingly, the authors of the PURE study did not make any claims about the benefits of full-fat dairy foods in their discussion of the results. These claims have all come from internet blogs and articles. Why were the authors of the study reluctant to make that claim? To answer that question I turned to reviews of the study published in the Science Media Center by experts in that field of study. Here were some of their comments:

Because dietary guidelines recommending the consumption of low-fat dairy foods exist primarily in western countries (specifically, the US, Canada & Europe) the distribution of low-fat dairy and full-fat dairy was not evenly divided between counties. Most of the low-fat dairy consumption occurred in western countries. In contrast, most of the full-fat dairy consumption occurred in developing countries. That introduces a couple of confounding variables that are unique to this study. For example:
- In developing countries, diets are often primarily plant-based and tend to be low in sugar and highly processed foods, while in western countries, diets are often primarily meat-based and are high in sugar and highly processed foods. The addition of full-fat dairy to a plant-based diet may not have the same effect as adding it to a pizza or hamburger.
In developing countries, people with higher incomes, a healthier lifestyle, and better access to health care are often the ones who consume more dairy products. In other words, the PURE study can’t tell us whether consumption of full-fat dairy lead to better health outcomes in those countries or whether wealthier and healthier people in those countries had the means to consume more dairy.
In many developing countries, a large segment of the population is lactose intolerant. Increased full-fat dairy consumption by these people would be largely yogurt and other fermented dairy foods which have health benefits of their own.

In short, confounding variables unique to this study make it difficult to say with confidence that full-fat dairy foods were just as beneficial as low-fat dairy foods.

In western countries the results of previous studies are mixed. Some suggest that full-fat dairy foods are just as effective as low-fat dairy foods at reducing heart disease risk. Others report that the primary heart-health benefits come from low-fat dairy foods.

Dairy Products and Heart Disease: Diet Context Matters

Why so much confusion? Some recent studies suggest that diet context matters. Simply put, that means the effect of the overall diet is more important than single food groups (dairy). To illustrate this point, let’s look at two other studies.

The first study (M Chen et al, The American Journal of Clinical Nutrition 104: 1209-1217, 2016 ) was published two years ago by investigators at the Harvard Chan School of Public Health. That study included data from 43,000 men in the Health Professionals Follow-Up Study, 87,000 women in the Nurses’ Health Study, and 90,000 women in the Nurses’ Healthy Study II. All these study participants were from the United States. This study put dairy fat consumption into the context of the overall diet. The main findings were:

Full-fat dairy foods did not increase heart disease risk compared to a diet that contains high amounts of refined carbohydrates and sugar (the typical American diet).
However, when dairy fat was replaced with the same number of calories from:
- vegetable fat, the risk of heart disease decreased by 10%.
- polyunsaturated fat, the risk of heart disease decreased by 24%.
- healthy carbohydrates (fruits, vegetables, and whole grains), the risk of heart disease decreased by 28%.

In other words, the effect of dairy fat on heart disease depends on the overall diet. If you add dairy fat to an already bad, heart-unhealthy diet, it does not further increase heart disease risk. (This finding may explain why several recent studies of western populations have found no difference between full-fat and low-fat dairy consumption.) However, this study also shows that addition of full-fat dairy to a heart-healthy diet is likely to increase heart disease risk.

The lead author of that study was quoted as saying: “These results suggest that dairy fat is not an optimal type of fat in our diets. Although one can enjoy moderate amounts of full-fat dairy such as cheese, a healthy diet pattern tends to be low in saturated fat. These results strongly support existing recommendations to choose mainly unsaturated fats from vegetable oils, nuts, seeds, avocados, and some oily fish for a heart-healthy diet.”

The second major study is the 7^th-Day Adventist study, which I have described in detail in my book “Slaying The Food Myths.” This study showed that a lacto-ovo vegetarian diet was less heart healthy than a vegan diet but is far heart-healthier than the typical American diet.

What Does This Study Mean For You?

Dairy foods are good for you: Increased consumption of dairy foods, milk, and yogurt are associated with decreased risk of heart disease. As I have said before, we have 5 food groups for a reason. Dairy foods are an essential part of a healthy diet.

If you are lactose-intolerant I have good news for you. Yogurt and other fermented dairy foods are probably even better for you than non-fermented dairy foods.
If you are avoiding dairy for other reasons, be sure to get your calcium, magnesium, and vitamin D from other sources. There may be other important nutrients in dairy that are heart-healthy, but these are the ones we are sure of.

The jury is still out on full-fat dairy products: It is best to follow current dietary guidelines and consume primarily low-fat dairy products.

If you are a cheese lover, it is probably OK to consume moderate amounts of cheese or other full-fat dairy foods on occasion as part of a heart-healthy, primarily plant-based diet. In short, it is probably better to add a little cheese to a green salad than it is to add it to pizza or a hamburger. It is probably better to pair your cheddar with an apple than with crackers.

Hopefully, this gives you a better understanding of the relationship between dairy products and heart disease.

The Bottom Line

A recent study looked at the consumption of dairy products and heart disease risk, and overall mortality risk in a study with 134,000 participants from 21 countries on five continents. The media response to this study has been overwhelming. Some of the recent headlines are:

Eating Dairy Foods Can Help Reduce Heart Disease Risk.
Fermented Dairy-Products May Protect Against Heart Attack.
Full-Fat Dairy May Actually Benefit Heart Health.
Eating Cheese Might Help You Live Longer.
Eating Cheese and Butter Every Day Linked To Living Longer.

The first two claims were supported by the study results. The claims about cheese and butter were wishful thinking. They were not supported by the study results. The claim about full-fat dairy was supported by the data, but the authors of the study did not make that claim because of study limitations.

Another recent study of 220,000 participants in the United States provides a better estimate of the effect of full-fat dairy foods on heart health. The main findings of this study were:

Full-fat dairy foods did not increase heart disease risk compared to a diet that contains high amounts of refined carbohydrates and sugar (the typical American diet).
However, when dairy fat was replaced with the same number of calories from:
- vegetable fat, the risk of heart disease decreased by 10%.
- polyunsaturated fat, the risk of heart disease decreased by 24%.
- healthy carbohydrates (fruits, vegetables, and whole grains), the risk of heart disease decreased by 28%.

In other words, the effect of dairy fat on heart disease depends on the overall diet. If you add full-fat dairy to an already bad heart-unhealthy diet, it does not further increase heart disease risk. However, if you add full-fat dairy to a heart-healthy diet, it is likely to increase heart disease risk.

For more details and a thorough discussion of the full-fat versus low-fat controversy 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.

Why You May Be Sore After A Massage

January 22, 2019 by Dr. Steve Chaney

Why You Sometimes Feel Worse Before You Feel Better

Author: Julie Donnelly, LMT –The Pain Relief Expert

Editor: Dr. Steve Chaney

Do you ever hurt after you’ve been to a massage therapist? Or maybe you’ve gone to the gym, or done yoga, after a long time away and you feel horrible the next day. You may decide that the massage therapist did something wrong, or that you’re better off not exercising or stretching. I’d like to explain what is happening when you have a negative effect after what you think should be helpful. You’ll begin to understand why you may be sore after a massage.

I’ve been a licensed massage therapist since 1989 and I’ve worked on thousands of people during these 30 years. Most people feel great after their session and continue to feel good for weeks afterward, but about 5% of people have what starts out as a negative result.

This negative situation has bothered me a great deal for all these years, and while I knew they would be okay, I didn’t know what to say to them while they were hurting. That is, I didn’t know until now! I’ve done a lot of research, and I spoke to a lot of professionals who specialize in treating pain symptoms. Everyone always gave me the same answer…”They’ll hurt for a bit and then feel wonderful.” That was encouraging, but it wasn’t enough to make me happy when I spoke to my clients.

I finally found an answer that explains the entire problem…it’s called “the Healing Crisis.”

What Is A Healing Crisis?

So, thanks to Google I found a website that is so well written that I’m going to share it with you. I want to give credit where it is due. The author of this information is Cindy Murdoch who is a staff writer for Underground Health. I tried to contact her for permission to share this info, but the website wasn’t responding, and I couldn’t find her by doing a Google search. So, I’ll just say, “Thank you Cindy” and share this with you.

I’ll synopsize the information here, but if you’re interested you can read the entire thing by going to https://www.alkawayusa.com/post/what-is-a-healing-crisis. Everything below that I copied from the website is in italics.

Sore After A Massage? Explanation

Healing Crisis: It’s Logical When You Read What Is Going On

Definition: A healing crisis, or healing reaction, is a temporary worsening of symptoms that occurs when the body is going through the process of healing itself through the elimination of toxins.

Even though the crisis is uncomfortable and sometimes alarming in nature, it is a good sign that the body is working to heal itself.

A healing crisis usually lasts two to three days, but can extend for much longer periods of time, even weeks. More than one healing crisis may be necessary for a complete cure to take place.

The Answer I Have Been Searching For Since 1989!

I am so happy to have found this website, and this article. This is exactly what I’ve always known in my heart, but I didn’t have the research to prove it. The article continues….

The stage is set for a healing crisis when the body is overloaded with toxins that have been trapped within its tissues for a long period of time – sometimes for many decades. As a general rule, the more toxic the body is, the more intense the healing crisis will be. As healing begins, many systems in the body work together to eliminate waste products and toxins and can become overwhelmed by the process. Remember, these symptoms are temporary, and once they pass, the body is healthier and stronger.

A healing crisis can also be produced by a treatment or therapy that causes yeast, viruses, bacteria, cancer cells, etc. to have massive die-offs. The dead cells can overwhelm the elimination processes as they are expelled from the body.

There are also ways to assist the body during a healing reaction. These can include: drinking plenty of fluids, especially water, to help carry off the toxins and getting plenty of rest – mentally, physically and emotionally.

In Summary

Healing crises are good even though they make you feel bad. They are a sign that the healing process chosen is working by eliminating the body of toxins, impurities and imbalances in the body.

The healing crisis lets you know that you are on the right path to renewed health and vigor. “No pain, no gain” is truly applicable when talking about a healing crisis.

Wishing you well,

Julie Donnelly

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.

About The Author

Julie Donnelly is a Deep Muscle Massage Therapist with 20 years of experience specializing in the treatment of chronic joint pain and sports injuries. She has worked extensively with elite athletes and patients who have been unsuccessful at finding relief through the more conventional therapies.

She has been widely published, both on – and off – line, in magazines, newsletters, and newspapers around the country. She is also often chosen to speak at national conventions, medical schools, and health facilities nationwide.

A Low Carb Diet and Weight Loss

January 15, 2019 by Dr. Steve Chaney

Do Low-Carb Diets Help Maintain Weight Loss?

Author: Dr. Stephen Chaney

Traditional diets have been based on counting calories, but are all calories equal? Low-carb enthusiasts have long claimed that diets high in sugar and refined carbs cause obesity. Their hypothesis is based on the fact that high blood sugar levels cause a spike in insulin levels, and insulin promotes fat storage.

The problem is that there has been scant evidence to support that hypothesis. In fact, a recent meta-analysis of 32 published clinical studies (KD Hall and J Guo, Gastroenterology, 152: 1718-1727, 2017 ) concluded that low-fat diets resulted in a higher metabolic rate and greater fat loss than isocaloric low-carbohydrate diets.

However, low-carb enthusiasts persisted. They argued that the studies included in the meta-analysis were too short to adequately measure the metabolic effects of a low-carb diet. Recently, a study has been published in the British Medical Journal (CB Ebbeling et al, BMJ 2018, 363:k4583 ) that appears to vindicate their position.

Are low carb diets best for long term weight loss?

Low-carb enthusiasts claim the study conclusively shows that low-carb diets are best for losing weight and for keeping it off once you have lost it. They are saying that it is time to shift away from counting calories and from promoting low-fat diets and focus on low-carb diets instead if we wish to solve the obesity epidemic. In this article I will focus on three issues:

How good was the study?
What were its limitations?
Are the claims justified?

How Was The Study Designed?

The investigators started with 234 overweight adults (30% male, 78% white, average age 40, BMI 32) recruited from the campus of Framingham State University in Massachusetts. All participants were put on a diet that restricted calories to 60% of estimated needs for 10 weeks. The diet consisted of 45% of calories from carbohydrate, 30% from fat, and 25% from protein. [So much for the claim that the study showed low-carb diets were more effective for weight loss. The diet used for the weight loss portion of the diet was not low-carb.]

During the initial phase of the study 161 of the participants achieved 10% weight loss. These participants were randomly divided into 3 groups for the weight maintenance phase of the study.

The diet composition of the high-carb group was 60% carbohydrate, 20% fat, and 20% protein.
The diet composition of the moderate-carb group was 40% carbohydrate, 40% fat, and 20% protein.
The diet composition of the low-carb group was 20% carbohydrate, 60% fat, and 20% protein.

Other important characteristics of the study were:

The weight maintenance portion of the study lasted 5 months – much longer than any previous study.
All meals were designed by dietitians and prepared by a commercial food service. The meals were either served in a cafeteria or packaged to be taken home by the participants.
The caloric content of the meals was individually adjusted on a weekly basis so that weight was kept within a ± 4-pound range during the 5-month maintenance phase.
Sugar, saturated fat, and sodium were limited and kept relatively constant among the 3 diets.

120 participants made it through the 5-month maintenance phase.

Do Low-Carb Diets Help Maintain Weight Loss?

The results were striking:

The low-carb group burned an additional 278 calories/day compared to the high-carb group and 131 calories/day more than the moderate-carbohydrate group.
These differences were even higher for those individuals with higher insulin secretion at the beginning of the maintenance phase of the study.
These differences lead the authors to hypothesize that low-carb diets might be more effective for weight maintenance than other diets.

What Are The Pros And Cons Of This Study?

This was a very well-done study. In fact, it is the most ambitious and well-controlled study of its kind. However, like any other clinical study, it has its limitations. It also needs to be repeated.

The pros of the study are obvious. It was a long study and the dietary intake of the participants was tightly controlled.

As for cons, here are the three limitations of the study listed by the authors:

#1: Potential Measurement Error: This section of the paper was a highly technical consideration of the method used to measure energy expenditure. Suffice it to say that the method they used to measure calories burned per day may overestimate calories burned in the low-carb group. That, of course, would invalidate the major findings of the study. It is unlikely, but it is why the study needs to be repeated using a different measure of energy expenditure.

#2: Compliance: Although the participants were provided with all their meals, there was no way of being sure they ate them. There was also no way of knowing whether they may have eaten other foods in addition to the food they were provided. Again, this is unlikely, but cannot be eliminated from consideration.

#3: Generalizability: This is simply an acknowledgement that the greatest strength of this study is also its greatest weakness. The authors acknowledged that their study was conducted in such a tightly controlled manner it is difficult to translate their findings to the real world. For example:

Sugar and saturated fat were restricted and were at very similar levels in all 3 diets. In the real world, people consuming a high-carb diet are likely to consume more sugar than people in the other diet groups. Similarly, people consuming the low-carb diet are likely to consume more saturated fat than people in the other diet groups.
Weight was kept constant in the weight maintenance phase by constantly adjusting caloric intake. Unfortunately, this seldom happens in the real world. Most people gain weight once they go off their diet – and this is just as true with low-carb diets as with other diets.
The participants had access to dietitian-designed prepared meals 3 times a day for 5 months. This almost never happens in the real world. The authors said “…these results [their data] must be reconciled with the long-term weight loss trials relying on nutrition education and behavioral counseling that find only a small advantage for low carbohydrate compared with low fat diets according to several recent meta-analyses.” [I would add that in the real world, people do not even have access to nutritional education and behavioral modification.]

What Does This Study Mean For You?

This study shows that under very tightly controlled conditions (dietitian-prepared meals, sugar and saturated fat limited to healthy levels, calories continually adjusted so that weight remains constant) a low-carb diet burns more calories per day than a moderate-carb or high-carb diet. These findings show that it is theoretically possible to increase your metabolic weight and successfully maintain a healthy weight on a low-carb diet. These are the headlines you probably saw. However, a careful reading of the study provides a much more nuanced viewpoint. For example, the fact that the study conditions were so tightly controlled makes it difficult to translate these findings to the real world.
In fact, the authors of the study acknowledged that multiple clinical studies show this almost never happens in the real world. These studies show that most people regain the weight they have lost on low-carb diets. More importantly, the rate of weight regain is virtually identical on low-carb and low-fat diets. Consequently, the authors of the current study concluded “…translation [of their results to the real world] requires exploration in future mechanistic oriented research.” Simply put, the authors are saying that more research is needed to provide a mechanistic explanation for this discrepancy before one can make recommendations that are relevant to weight loss and weight maintenance in the real world.
The authors also discussed the results of their study in light of a recent, well-designed 12-month study (CD Gardener et al, JAMA, 319: 667-669, 2018 ) that showed no difference in weight change between a healthy low-fat versus a healthy low-carbohydrate diet. That study also reported that the results were unaffected by insulin secretion at baseline. The authors of the current study noted that “…[in the previous study] participants were instructed to minimize or eliminate refined grains and added sugars and maximize intake of vegetables. Probably for this reason, the reported glycemic load [effect of the diet on blood sugar levels] of the low-fat diet was very low…and similar to [the low-carb diet].” In short, the authors of the current study were acknowledging that diets which focus on healthy, plant-based carbohydrates and eliminate sugar, refined grains, and processed foods may be as effective as low-carb diets for helping maintain a healthy weight.
This would also be consistent with previous studies showing that primarily plant-based, low-carb diets are more effective at maintaining a healthy weight and better health outcomes long-term than the typical American version of the low-fat diet, which is high in sugar and refined grains. In contrast, meat-based, low-carb diets are no more effective than the American version of the low-fat diet at preventing weight gain and poor health outcomes. I have covered these studies in detail in my book “Slaying The Food Myths.”

Consequently, the lead author of the most recent study has said: “The findings [of this study] do not impugn whole fruits, beans and other unprocessed carbohydrates. Rather, the study suggests that reducing foods with added sugar, flour, and other refined carbohydrates could help people maintain weight loss….” This is something we all can agree on, but strangely this is not reflected in the headlines you may have seen in the media.

The Bottom Line

A recent study compared the calories burned per day on a low-carb, moderate-carb, and high-carb diet. The study concluded that the low-carb diet burned significantly more calories per day than the other two diets and might be suitable for long-term weight control. If confirmed by subsequent studies, this would be the first real evidence that low-carb diets are superior for maintaining a healthy weight.
However, the study has some major limitations. For example, it used a methodology that may overestimate the benefits of a low-carb diet, and it was performed under tightly controlled conditions that can never be duplicated in the real world. As acknowledged by the authors, this study is also contradicted by multiple previous studies. Further studies will be required to confirm the results of this study and show how it can be applied in the real world.
In addition, the kind of carbohydrate in the diet is every bit as important as the amount of carbohydrate. The authors acknowledge that the differences seen in their study apply mainly to carbohydrates from sugar, refined grains, and processed foods. They advocate diets with low glycemic load (small effects on blood sugar and insulin levels) and acknowledge this can also be achieved by incorporating low-glycemic load, plant-based carbohydrates into your diet. This is something we all can agree on, but strangely this is not reflected in the headlines you may have seen in the media.
Finally, clinical studies report averages, but none of us are average. When you examine the data from the current study, it is evident that some participants burned more calories per hour on the high-carb diet than other participants did on the low carb diet. That reinforces the observation that some people lose weight more effectively on low-carb diets while others lose weight more effectively on low-fat diets. If you are someone who does better on a low-carb diet, the best available evidence suggests you will have better long-term health outcomes on a primarily plant-based, low-carb diet such as the low-carb version of the Mediterranean diet.

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.

What Are Intermittent Fasting Benefits?

January 8, 2019 by Dr. Steve Chaney

Will Intermittent Fasting Make You Leaner & Healthier?

Author: Dr. Stephen Chaney

Intermittent fasting is all the rage. If you believe the hype, intermittent fasting will make you leaner and healthier. Some of its proponents claim you don’t even need to give up your favorite foods. You don’t need to give up your Big Macs for fruits and vegetables. You don’t need to restrict what you eat. You just need to restrict when you eat.

If you read the blogs about intermittent fasting, you will come across all sorts of metabolic mumbo-jumbo about ketone bodies, adiponectin, leptin, IGF-1, and blood glucose levels. It sounds so convincing. Don’t get sucked in by these pseudo-scientific explanations. At this point they are mostly speculation.

What are intermittent fasting benefits?

Instead, ask “What is the evidence that intermittent fasting works?” More importantly, ask “What is the evidence it works in human?” Most of the studies have been done in animal model systems. Claims based on animal models may not apply to humans.

This week I will discuss a review on caloric restriction and various forms of fasting that recently appeared in Science, one of the most highly respected scientific journals (Di Francesco et al, Science, 362: 770-775, 2018 ).

This article was a comprehensive review of three closely-related dietary approaches:

Caloric restriction in which daily caloric intake is restricted by 15-40%.
Time-restricted fasting which limits daily intake of food to a 4-12 hour period.
Intermittent fasting in which there is a day or more of fasting or decreased food intake between periods of unrestricted eating.

Note:

What the review calls time-restricted fasting is referred to in the mass media as intermittent fasting. What the review calls intermittent fasting is referred to in the mass media as alternate day fasting. To avoid confusion, I will use the mass media definitions.
I will focus on what the mass media refers to as intermittent fasting and just briefly summarize the other two approaches.

Will Caloric Restriction Allow You To Live Longer?

The concept of caloric restriction has been around for a long time and is the best studied of the dietary approaches covered in this review. In brief:

Caloric restriction has been studied in animal model systems ranging from mice to primates. In every animal model studied, caloric restriction reduced the incidence of age-related degenerative diseases and increased either life span or health span or both.
In both animal model systems and humans, caloric restriction lowers cholesterol, lowers blood pressure, improves blood sugar control, reduces inflammation, and reduces oxidative damage.
Populations that eat a healthy diet and practice voluntary caloric restriction appear to enjoy remarkable longevity.
The effects of caloric restriction appear to operate via the sirtuin anti-aging pathway. Most of the other effects are downstream of this pathway.
The effects of caloric restriction (including activation of the sirtuin pathway) are mimicked by resveratrol and related polyphenols.

In short:

Caloric restriction and some naturally occurring compounds such as resveratrol are clearly effective in animal model systems and are likely to be effective in humans.
However, we live too long to allow definitive studies of the effect of caloric restriction on human life span and health span.
This dietary approach has never gained popularity because very few people want to starve themselves just so they can live a longer, healthier life.

Intermittent Fasting Benefits: Leaner & Healthier?

There are many variations to intermittent fasting. As the review stated, intermittent fasting can mean that food consumption is restricted to anywhere from 4 to 12 hours. However, the most popular version of intermittent fasting at present restricts food consumption to 8 hours followed by a 16-hour period of fasting. Here is what you need to know about intermittent fasting:

Once again, most of the studies have been done in rodents. Those studies appear to show that intermittent fasting results in weight loss, improved blood sugar control, lower cholesterol and triglyceride levels and reduced inflammation even when caloric intake remains unchanged. These findings have generated the claims you see in the media. However, you need to remember that what works in rodents does not necessarily work in humans.
Unlike caloric restriction, the benefits of intermittent fasting are dependent on circadian rhythm. [Note: If you are unfamiliar with the concept of circadian rhythm, it is a master control that is genetically hardwired into almost every organism on the planet, including humans. In general, circadian rhythm is synchronized with the light-dark cycle.] The effect of circadian rhythm that is relevant to this discussion is that metabolic rate and many of the enzymes involved in food metabolism in humans are more active during the day than at night. Not surprising, animal studies suggest that intermittent fasting is most effective when the feed-fast cycle is synchronized with their circadian rhythm.
The timing of the feeding portion of the intermittent fasting cycle also appears to be important for humans. According to the review by Di Francesco et al, the few clinical studies that have been performed on humans show:
Limiting food intake to the middle of the day decreased glucose levels, cholesterol & triglyceride levels, and inflammation.
Eating a larger breakfast and smaller dinner improved metabolic markers better than when participants ate a smaller breakfast and larger dinner.
Type 2 diabetics attained better blood sugar control when most of their calories were consumed in the first half of the day. In contrast, restricting their calories to late afternoon or evening resulted in either no blood sugar improvement or a worsening of blood sugar controls.
Finally, subjects lost more weight on a reduced calorie diet when most of the food was consumed in the morning rather than in the evening.
If you read the very popular “Obesity Code” book by Dr. Fung you will discover he is recommending a diet that consists of fruits & vegetables, fiber-rich foods, healthy protein & healthy fats, and avoids sugar, refined grains, and processed foods. He also recommends avoiding snacking. That is exactly the kind of diet I recommend in my book, “Slaying The Food Myths.” If the average American adopted that diet and did nothing else, they would be leaner and healthier. So much for the claim that you can eat all your favorite junk foods and become leaner and healthier by intermittent fasting.
Finally, most of the human clinical studies have carefully controlled caloric intake. From these studies it is apparent that many of the metabolic benefits of intermittent fasting come from synchronizing your food intake with your circadian rhythm. However, in those studies that focused on time of eating and did not control calories, food intake was reduced by intermittent fasting. This is the unacknowledged benefit of intermittent fasting. When you restrict the time period for eating and restrict snacking you generally end up eating less. Thus, the weight loss associated with intermittent fasting may be caused by reduced caloric intake rather than fasting.

What Does This Mean For You? Here are the take-home lessons from this review:

Most of the studies on intermittent fasting have been done with animals, not with humans.
Both animal and human studies suggest that the benefits of intermittent fasting result from synchronizing your food intake with your circadian rhythm. The old adage of “Eat breakfast like a king, lunch like a prince, and dinner like a pauper” may be true for most of us. [Note: Circadian rhythms vary slightly from person to person. Some people will do better by their fast at mid-day rather than at breakfast. However, they will probably still benefit by eating a bigger meal mid-day and a smaller meal in the evening.]
Although there is no conscious effort to control calories, intermittent fasting appears to result in an inadvertent reduction in food intake by restricting the time allowed for eating and by eliminating late night snacking. This reduction in caloric intake is likely responsible for much of the weight loss associated with intermittent fasting.
In summary, intermittent fasting appears to work, but it is not clear whether you need to follow a rigid schedule of eating and fasting. The available clinical studies suggest that if you eat a healthy, primarily plant-based diet, eat most of your calories early in the day, don’t snack between meals, and don’t eat anything after dinner, you will obtain most, if not all, of the benefits attributed to intermittent fasting.

If you define intermittent fasting that way, the professor has been doing intermittent fasting for years. He just didn’t know that was what he was doing.

Does Alternate Day Fasting Make You Healthier?

Fasting regimens promoted for weight loss typically involve one or several days in which no or few calories are consumed followed by a period of unrestricted eating.

At present, the two most popular regimens are the alternate day fast and the alternate day modified fast. The alternate day fast involves a 24-hour water fast followed by a normal feeding period of 24-hours. The alternate day modified fast reduces caloric intake to 25% of normal on fasting days. Here is a brief summary of what we know about alternate day fasting:

Once again, most of the studies have been done in animals.
Since neither animals nor humans generally consume double their normal caloric intake during the 24-hour feeding period, alternate day fasting results in an overall reduction in caloric intake. Not surprisingly, the benefits of alternate day fasting in animal studies are similar to the benefits observed with caloric restriction.
Short-term human clinical trials suggest that alternate day fasting results in weight loss. The weight loss causes an improvement in blood sugar control, lower blood pressure, and lower cholesterol & triglyceride levels. Based on these studies, alternative day fasting is likely to be an effective strategy for short-term weight loss and has some short-term health benefits.
However, there are no long-term studies on the effectiveness of this approach. It is highly unlikely that most people would be able to follow this regimented a diet plan long term. Thus, it is also unlikely that the weight loss and health benefits can be maintained long term.
Finally, fasting is not for everyone. It is generally not recommended for people who are hypoglycemic, the elderly, pregnant women, and people with eating disorders.

The Bottom Line

In this article I discussed a recent review of intermittent fasting and other approaches that involved fasting or long-term caloric restriction. Here are the take-home lessons on intermittent fasting:

Most of the studies on intermittent fasting have been done with animals, not with humans. Many of the claims you hear about on the benefits of intermittent fasting are based on the animal studies. They may not apply to humans.
Both animal and human studies suggest that the benefits of intermittent fasting result from synchronizing your food intake with your circadian rhythm. The old adage of “Eat breakfast like a king, lunch like a prince, and dinner like a pauper” may be true for most of us. [Note: Circadian rhythms vary slightly from person to person. Some people will do better by breaking their fast at mid-day rather than at breakfast. However, they will probably still benefit by eating a bigger meal mid-day and a smaller meal in the evening.]
Although there is no conscious effort to reduce calories, intermittent fasting appears to result in an inadvertent reduction in food intake by restricting the time allowed for eating and by eliminating late night snacking. This reduction in caloric intake is likely responsible for much of the weight loss associated with intermittent fasting.
In summary, intermittent fasting appears to be beneficial, but it is not clear whether you need to follow a rigid schedule of eating and fasting. The available clinical studies suggest that if you eat a healthy, primarily plant-based diet, eat most of your calories early in the day, don’t snack between meals, and don’t eat anything after dinner, you will obtain most, if not all, of the benefits attributed to intermittent fasting. If you define intermittent fasting that way, the professor has been doing intermittent fasting for years. He just didn’t know that was what he was doing.

For more details on intermittent fasting and for a discussion of long-term caloric restriction and alternate day fasting 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.

300th Issue Celebration: The Latest Developments in Health, Nutrition & Fitness

January 2, 2019 by Dr. Steve Chaney

Nutrition Breakthroughs Over The Last Two Years

Author: Dr. Stephen Chaney

In the six years that I have been publishing “Health Tips From The Professor,” I have tried to go behind the headlines to provide you with accurate, unbiased health information that you can trust and apply to your everyday life. The 300^th issue of any publication is a major cause for celebration and reflection, especially when its publication coincides with the first day of a brand-new year – and “Health Tips From The Professor” is no different.

I am dedicating this issue to reviewing some of the major stories I have covered in the past 100 issues. There are lots of topics I could have covered, but I have chosen to focus on three types of articles:

Articles that have debunked long-standing myths about nutrition and health.
Articles that have corrected some of the misinformation that seems to show up on the internet on an almost daily basis.
Articles about the issues that most directly affect your health.

What Diets Are Best For Weight Loss?

Since this review is being written in January, let’s start with some of the articles about diets and weight loss. I have covered the effectiveness of the Paleo, Keto, Mediterranean, DASH, vegetarian, and Vegan diets for both short and long-term weight loss in my book “Slaying The Food Myths,” so I won’t repeat that information here. Instead, I will cover the popular Whole 30 Diet. I will also address the value of DNA tests in predicting which diet is best for you when it comes to weight loss.

I reviewed the Whole 30 Diet this past January. There is a lot to like about this diet, but some things to dislike as well. Here is a brief summary: Because it is a very rigid diet, it is excellent for short-term weight loss. What is less clear is whether it is good for weight maintenance or is even healthy over the long term. For more details, check out my article The Whole 30 Diet.

As for DNA testing, my recent article, Can Genetics Predict Which Diet is Best for You, in Health Tips From The Professor reviewed a study that looked at the value of DNA tests at predicting whether a low carb or low fat diet would be better at helping you lose weight. The article made some interesting observations about the relative value of low-carb and low-fat diets for weight loss. However, the most important conclusion of the study was that DNA testing was of no value at predicting whether a low-carb or low-fat diet would be the best weight loss strategy for you.

Can Diet Influence Long-Term Health Outcomes?

This topic was a major focus of “Slaying The Food Myths.”

Let me start with a quiz:

Which diet decreases heart disease risk by 50% (Mediterranean Diet for Heart Health)?
Which diet decreases both heart disease and diabetes risk by 50% (Diet, Type 2 Diabetes and Heart Disease)?
Which diet decreases the risk of premature death by 31% (Premature Death Risk)?

Hint: The answer is slightly different in each case, but these are all whole-food, primarily plant-based diets. If you have forgotten the details, you may wish to check these articles out.

Here are some articles that didn’t make it into the book:

Can diet reduce ADHD symptoms (Diet for Children with ADHD)?
Can diet reduce Alzheimer’s risk (Can Diet Reduce Alzheimer’s Risk)?
Can diet reduce prostate cancer risk (Best Diet to Prevent Cancer)?
Can diet reduce colon cancer risk (Colon Cancer Prevention)?

The answer to each of these questions appears to be yes. If any of these are a concern for you, you’ll want to read the corresponding article.

Food Controversies And Your Health

I discussed a lot of food controversies in “Slaying The Food Myths,” but here are a few that didn’t make it into the book.

“Are High Fat Dairy Foods Good For You?”
“Are Eggs Good For Your Heart?”
Is meat bad for your heart? There are two recent studies that came to opposite conclusions on this important topic. To evaluate the evidence, you need to look at both studies.
- “Is Meat Heart Healthy?”
- “Does Meat Protein Increase Heart Disease Risk?”

“The Truth About Low-Carb Diets.” What do the latest studies show?

Junk Foods And Your Health

I discussed sugar myths and pointed out that artificially sweetened foods were no better for you in “Slaying The Food Myths.” Here are some other topics that may be of interest.

“Does Sucralose Make You Hungry?”
“When Is Fructose Bad For You (and when is it good for you)?”
“Do Processed Foods Increase Your Risk of Cancer?”
“Are Fast Foods Killing Our Kids?”

Myths That Supplements Are Worthless

In my book “Slaying The Supplement Myths” I showed that many of the claims that supplements were either worthless or dangerous were simply myths kept alive by the pharmaceutical/medical industry and “Dr. Strangelove’s” nutrition blogs. For example, in my book I listed clinical studies that have disproved claims that:

Soy causes breast cancer
Methylfolate is required for everyone with MTHFR deficiency
Folic acid causes colon cancer.
Vitamin E and selenium cause prostate cancer.
B6 and B12 cause lung cancer in men.
Calcium supplements cause heart disease.

Just to name a few. However, new studies suggesting that supplements may be ineffective keep emerging, and each study is ballyhooed by the pharmaceutical/medical industry and the media. Let me update you with my reviews of studies that have been published since my book was written.

However, before I do that, let me put the controversies into perspective by looking at the strengths and weaknesses of the clinical studies behind the headline. I have written two articles on that topic in the past two years.

In “Are Clinical Studies Misleading?” I discuss the reasons why the same kind of clinical studies that work well for determining the efficacy of drugs are ill suited for determining the efficacy of supplements.
In “None Of Us Are Perfect” I point out that clinical studies are based on averages, and none of us are average. What worked for most participants in the study, might not work for you. Conversely, even if a supplement did not work for the average participant in a study, it might work for you.

With that in mind, lets look at some recent studies that have made the headlines.

Omega-3s And Heart Disease Risk

I covered this topic in detail in my book. However, four recent studies have been published since the book was written. One of the studies declared that omega-3s were worthless at reducing heart disease risk. The other three studies were much more positive, although you wouldn’t know that from some of the headlines in the media.

You will find my analysis of the negative study in “Do Omega-3s Reduce Heart Disease Risk?”
You will find my analysis of the three positive studies in:
- “Omega-3s And Heart Disease Risk.”
- “Are Omega-3 Supplements Good For You?”

The bottom line is that evidence for a beneficial effect of omega-3 supplements on reducing heart disease risk is becoming much stronger, although you probably won’t hear that from your doctor or the media. If you want to know how much and what kind of omega-3s are optimal, you will want to read my articles.

Vitamin D: Myths Versus Truth

Two recent studies have been published questioning the importance of vitamin D supplementation. The first study claimed that vitamin D supplementation was ineffective for maintaining healthy bones in the elderly. If you believed the headlines, the second study showed that vitamin D was ineffective at reducing both heart disease and cancer. If you read the paper, you discovered that the authors did show benefits of vitamin D at preventing cancer deaths in the general population and reducing cancer risk in high risk groups. However, both studies suffered from some serious flaws that limited the ability of the studies to clearly demonstrate the benefits of vitamin D supplementation.

You will find my analysis of the vitamin D and bone health study in “Are Vitamin D Supplements Worthless?”
You will find my analysis of the vitamin D, heart health, and cancer study in “The Truth About Vitamin D.”
In “Does Vitamin D Reduce Cancer Risk?” you will find my review of another major clinical study that concluded vitamin D does reduce cancer risk. That study also shows why it has been so difficult for other studies to demonstrate a clear benefit of vitamin D at reducing cancer risk.

The “Dark Side” Of The Food Supplement Industry

I covered the dark side of the supplement industry in great detail in my book “Slaying The Supplement Myths.” Here are a few more examples that have crossed my desk since the book was written:

In “Is The Jellyfish Memory Supplement A Hoax?” I give another example of what the FTC describes as junk science and misleading advertising.
In “Are Curcumin (Turmeric) Benefits Bogus?” I give another example of why it is so important to base supplement claims on clinical studies rather than cell culture and animal studies.
In “Exposing The Dark Side Of The Supplement Industry” I give examples of adulteration (substitution of cheaper ingredients for the ingredient claimed on the label), supplements that are dangerous, and misleading product claims.

What Does The Future Hold?

I have just touched on a few of my most popular articles in the list I gave you above. You may want to scroll through that list to find articles of interest to you that you might have missed. If you don’t see what you are looking for, just go to https://www.chaneyhealth.com/healthtips and type the appropriate term in the search box.

In the coming year, you can look for more articles debunking myths, exposing lies and providing balance to the debate about the health topics that affect you directly. As always, I pledge to provide you with scientifically accurate, balanced information that you can trust. I will continue to do my best to present this information in a clear and concise manner so that you can understand it and apply it to your life.

If you have other topics that you would like me to cover, please click on the link below to enter your suggestions in the comment box.

Final Comment: You may wish to share the valuable resources in this article with others. If you do, then copy the link at the top and bottom of this page into your email. If you just forward this email and the recipient unsubscribes, it will unsubscribe you as well.

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.

Merry Christmas

December 25, 2018 by Dr. Steve Chaney

Merry Christmas 2018

Author: Dr. Stephen Chaney

The Christmas season is a wonderful time of year. It is a time when we get together with family and reconnect with friends. It’s a time of year when we remember the joy of giving and the joy of making the world a better place.

For those of us who are Christians, it is a time to remember that God gave us his only son. But, no matter what our religion, it is a time of year when we can focus on the common beliefs we share and the true purpose of our lives here on earth. It is a time to share the Christmas spirit of peace on earth and good will to all.

The Professor and his family wish you a blessed Christmas and happy, healthy & prosperous New Year.

Enjoy A Stress-Free Holiday Season

December 18, 2018 by Dr. Steve Chaney

Stay Pain Free

Author: Julie Donnelly, LMT –The Pain Relief Expert

Editor: Dr. Steve Chaney

Welcome To December – It’s The Most Wonderful Time Of Year

This is such a beautiful season with lots of special events filling up our time. There are holiday gatherings and good food, in fact, even the TV commercials are more fun to watch than normal. But, how do we still enjoy a stress-free holiday?

This time of year is a mixed blessing for many people. The fun of getting together with friends and family can be tempered with the stress of trying to do too much in a limited time, and the additional stress of the extra financial outlay. It’s easy to forget to take care of ourselves when we’re focusing on a long “to-do” list.

Enjoy A Stress-Free Holiday Season

Here’s a quick 3-minute relaxation technique that will help bring peace and release stress:

Sit in a comfortable chair. Have your hands relaxed at your side, and your feet flat on the floor.
Take 2-3 slow, deep breaths…breathing out tension and mentally sinking down into the chair.
Visualize tension melting like ice cream, starting at your forehead and slowly going all the way down your body until it is flowing out through your fingertips and toes. Enjoy the feeling as the tension is draining away.
Next, visualize pure, positive energy in the form of diamond-dust showering you, moving down from your head and flowing out through your hands and feet. “See” it sparkling…pink, blue, yellow…shining crystals that bring calmness to your body.

Enjoy the feeling for as long as possible before slowly coming back to reality. Once you have done this a few times you’ll be able to sit quietly and fast-forward the entire process to less than a minute.

You Are Your Own Best Therapist

YOU are your own Best Therapist! Visit www.JulstroMethod.com and www.FlexibleAthlete.com to discover logical answers to questions about chronic pain and repetitive strain injuries.

Wishing you well,

Julie Donnelly

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.

About The Author

The Truth About Vitamin D

December 11, 2018 by Dr. Steve Chaney

Does Vitamin D Reduce Risk Of Heart Disease & Cancer?

Author: Dr. Stephen Chaney

You have every right to be confused. One day you are told that vitamin D reduces your risk of heart disease and cancer. The next day you are told vitamin D makes has no effect on those diseases. You are told vitamin D is a waste of money. What should you believe? What is the truth about vitamin D?

In mid-November a major clinical study called VITAL was published. It examined the effect of vitamin D and omega-3s on heart disease and cancer risk. Last week I wrote about the omega-3 portion of the study. This week I will cover the vitamin D portion of the study.

Once again, if you rely on the media for your information on supplementation, you are probably confused. Headlines ranged from “Vitamin D Is Ineffective For Preventing Cancer And Heart Disease to “Vitamin D Lowers Odds Of Cancer Death.” What is the truth?

The problem is that reporters aren’t scientists. They don’t know how to interpret clinical studies. What they report is filtered through their personal biases. That is why I take the time to carefully evaluate the clinical studies, so I can provide you with accurate information. Let me sort through the dueling headlines and give you the truth about vitamin D, cancer, and heart disease.

How Was The Study Designed?

The VITAL study (JE Manson et al, New England Journal of Medicine, DOI: 10.1056/NEJMoa1811403) enrolled 25,871 healthy adults (average age = 67) in the United States. The study participants were 50% female, 50% male, and 20% African American. None of the participants had preexisting cancer or heart disease. The characteristics of the study group were typical of the American population at that age, namely:

The average BMI was 28, which means that most of the participants were significantly overweight.
7% of them had diabetes.

Study participants were given questionnaires on enrollment to assess clinical and lifestyle factors including dietary intake. Blood samples were taken from about 65% of the participants to determine 25-hydroxyvitamin D levels (a measure of vitamin D status) at baseline and at the end of the first year. The participants were given either 2,000 IU of vitamin D/day or a placebo and followed for an average of 5.3 years.

There were two important characteristics of the participants in this study that may have influenced the outcome.

The average 25-hydroxyvitamin D level of participants at the beginning of the study was 31 ng/ml (78 nmol/L). The NIH considers 20-50 ng/ml (50-125 nmol/L) to be the optimal level of 25-hydroxyvitamin D for most physiological functions. This means that study participants started in the middle of the optimal range with respect to vitamin D status.

[Note: The NIH defines the 20-50 ng/ml range as “adequate.” However, I know many of my readers like to aim beyond adequate to reach what they consider to be “optimal.” In the case of vitamin D, that might not be a good idea. The NIH considers anything above 50 ng/ml as associated “with potentially adverse effects.” For that reason, I will refer to the 20-50 ng/ml range as optimal for this article. I wouldn’t want to encourage my readers to be aiming for above 50 ng/ml.]

Only 12.7% of participants had 25-hydroxyvitamin D levels below 20 ng/ml, which the NIH considers to be inadequate. The results with this group were not statistically different from the study participants with optimal vitamin D status, but it is not clear that there were enough people in this subgroup for a statistically valid comparison with participants starting with an optimal vitamin D status.
At the end of the first year, 25-hydroxyvitamin D levels in the treatment group increased to 42 ng/ml (105 nmol/L), which is near the upper end of the optimal range. Thus, for most of the participants, the study was evaluating whether there was a benefit of increasing vitamin D status from the middle to the upper end of the optimal range.
The study allowed subjects to continue taking supplements that contained up to 800 IU of vitamin D. While the authors tried to correct for this statistically, it is a confounding variable.

Does Vitamin D Reduce The Risk Of Cancer?

You may remember from last week that omega-3s were more effective for reducing heart disease risk than for reducing cancer risk. What is the truth about vitamin D and cancer risk? The results are reversed for vitamin D, so I will discuss cancer first.

The study reported that vitamin D supplementation did not reduce a diagnosis of invasive cancer of any type, breast cancer, prostate cancer, or colon cancer during the 5.3-year time-period of this study. This was the result that was reported in the abstract and was what lazy journalists, who never read past the abstract, reported.

However, the rest of the study was more positive. For example, occurrence of invasive cancer of any type was reduced by:

23% in African-Americans.
24% in patients with a healthy body weight.

Several previous studies have suggested that vitamin D may be more effective at preventing cancer in people with a healthy body weight, but the mechanism of this effect is currently unknown.

Most previous studies have not included enough African-Americans to determine whether they respond more favorably to vitamin D supplementation. However, African-Americans have a higher risk of cancer, so this finding deserves follow-up.

In addition, when the study looked at deaths from cancer, the results were very positive. For example:

Cancer deaths during the 5.3-year study period were reduced by 17%.
The longer vitamin D supplementation was continued the more effective it became at reducing cancer deaths. For example,
When the authors excluded cancer deaths occurring during the first year of supplementation, vitamin D reduced cancer deaths by 21%.
When the authors excluded cancer deaths occurring during the first two years of supplementation, vitamin D reduced cancer deaths by 25%.

Finally, no side effects were noted in the vitamin D group.

Does Vitamin D Reduce The Risk Of Heart Disease?

The VITAL study also looked at the effect of vitamin D on heart disease risk. What is the truth about vitamin D and heart disease? The results from this study were uniformly negative. There was no effect of vitamin D supplementation on all major cardiovascular events combined, heart attack, stroke, or death from heart disease. Does that mean vitamin D has no role in reducing heart disease risk? That’s not clear.

The authors had a thought-provoking explanation for why the results were negative for heart disease, but positive for cancer. Remember that the participants in this trial started with a 25-hydroxyvitamin D level of 31 ng/ml and increased it to at least 42 ng/ml with vitamin D supplementation.

The authors stated that previous studies have suggested the 25-hydroxyvitamin D level associated with the lowest risk for heart disease is between 20 and 25 ng/ml. If that is true, most of the participants in this trial were already in the lowest possible risk for heart disease with respect to vitamin D status before the study even started. There would be no reason to expect additional vitamin D to further reduce their risk of heart disease.

In contrast, the authors said that previous studies suggest the 25-hydroxyvitamin D level associated with the lowest risk of cancer deaths is above 30 ng/ml. If that is true, it would explain why vitamin D supplementation in this study was effective at reducing cancer deaths.

However, previous placebo-controlled clinical studies have also been inconclusive with respect to vitamin D and heart disease. My recommendation would be to think of adequate vitamin D status as part of a holistic approach to reducing heart disease – one that includes a heart-healthy diet and a heart-healthy lifestyle – rather than a “magic bullet” that decreases heart disease risk by itself.

As for heart-healthy diets, I discuss the pros and cons of various diets in my book, “Slaying The Food Myths.” As I discuss in my book, the weight of scientific evidence supports primarily plant-based diets that include omega-3s as heart healthy. As an example, the Mediterranean diet is primarily plant-based and is rich in healthy oils like olive oil and omega-3s. It is associated with reduced risk of both heart disease and cancer.

What Is The Truth About Vitamin D?

There is a lot of confusion around the question of whether vitamin D reduces the risk of cancer. This study strengthened previous observation suggesting that vitamin D supplementation decreases cancer deaths. However, it is also consistent with previous studies that have failed to find an effect of vitamin D on cancer development. How can we understand this apparent discrepancy? The authors provided a logical explanation. They pointed out that:

Cancer development takes 20-30 years while this clinical study lasted only 5.3 years. That means that vitamin D supplementation only occurred at the tail end of the cancer development process. In fact, the cancer was already there in most of the patients in the study who developed cancer. It just had not been diagnosed yet. In the words of the authors: “Given the long latency for cancer development, extended follow-up is necessary to fully ascertain potential effects [of vitamin D supplementation].”
In contrast, none of the patients had been diagnosed with cancer when they entered the trial. That means that the patients were diagnosed with cancer during the 5.3-year study period. They were receiving extra vitamin D during the entire period of cancer treatment. Thus, the effect of vitamin D on reducing cancer deaths was easier to detect.

What Does This Study Mean For You?

Vitamin D Is Likely To Decrease Your Risk Of Dying From Cancer: When you combine the results of this study with what we already know about vitamin D and cancer, the results are clear. Vitamin D appears to reduce your risk of dying from cancer. More importantly, the longer you have been supplementing with vitamin D, the greater your risk reduction is likely to be.

Vitamin D May Decrease Your Risk Of Developing Cancer: Association studies suggest that optimal vitamin D status is associated with decreased cancer risk, especially colon cancer risk. However, the long time for cancer development means that we may never be able to prove this effect through double-blind, placebo-controlled clinical trials.

Holistic Is Best: When you combine the VITAL study results with what we already know about vitamin D and heart disease, it appears that supplementing with vitamin D is unlikely to reduce your risk of developing heart disease unless you are vitamin D deficient. However, a holistic approach that starts with a healthy, primarily plant-based diet and makes sure your vitamin D status is adequate is likely to be effective.

The same is likely true for cancer. While the latest study suggests that vitamin D supplementation reduces your risk of dying from cancer, those vitamin D supplements are likely to be even more effective if you also adopt a healthy diet and lifestyle.

How Much Vitamin D Do You Need? The optimal dose of vitamin D is likely to be different for each of us. One of the things we have learned in recent years is that there are significant differences in the efficiency with which we convert vitamin D from diet and/or sun exposure into the active form of vitamin D in our cells. Fortunately, the blood test for 25-hydroxyvitamin D is readily available and is widely considered to be an excellent measure of our vitamin D status.

I recommend that you have your blood level of 25-hydroxyvitamin D tested on an annual basis. Based on the best currently available data, I recommend you aim for >20 ng/ml (50 nmol/L) if you wish to minimize your risk of heart disease and >30 ng/ml (75 nmol/L) if you wish to minimize your risk of cancer. If you can achieve those levels through diet and a multivitamin supplement, that is great. If not, I would recommend adding a vitamin D supplement until those levels are achieved.

Finally, you shouldn’t think of vitamin D as a magic bullet. If you are a couch potato and eat sodas and junk food, don’t expect vitamin D to protect you from cancer and heart disease. You should think of maintaining adequate 25-hydroxyvitamin D levels as just one component of a holistic approach to healthy, disease-free living.

The Bottom Line

There is a lot of confusion around the question of whether vitamin D reduces the risk of cancer and heart disease. A major clinical study has just been published that sheds light on these important questions. It reported:

Vitamin D did not decrease the risk of developing cancer during the 5.3-year study duration. The authors pointed out that cancer takes 20-30 years to develop, which means their study was probably too short to detect an effect of vitamin D on the risk of developing cancer.
Vitamin D did decrease the risk of dying from cancer, and the longer people were supplementing with vitamin D the bigger the protective effect of vitamin D was.
Vitamin D did not decrease the risk of heart disease. However, most study participants had a level of 25-hydroxyvitamin D that was optimal for reducing the risk of heart disease at the beginning of the study. There was no reason to expect that extra vitamin D would provide additional benefit.
With respect to both cancer and heart disease the best advice is to:
- Get your 25-hydroxyvitamin D levels tested on an annual basis and supplement, if necessary, to keep your 25-hydroxyvitamin D levels in what the NIH considers to be an adequate range (20-50 ng/ml).
- We do not have good dose response data for the beneficial effects of vitamin D on heart disease and cancer. However, according to this article, previous studies suggest you may want to am for 25-hydroxyvitamin D levels above 20 ng/ml to reduce the risk of heart disease and above 30 ng/ml to reduce your risk of cancer.
- Consider vitamin D as just one component of a holistic approach to healthy, disease-free living.

For more details about the interpretation of these studies and what they mean 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.

Are Omega-3 Supplements Good For You?

December 4, 2018 by Dr. Steve Chaney

Do Omega-3s Reduce Risk Of Heart Disease & Cancer?

Author: Dr. Stephen Chaney

Are omega-3 supplements good for you?

You have every right to be confused. In the late 1990s and early 2000s several major clinical studies showed that omega-3 supplements reduced the risk of heart attacks and stroke. In contrast, a few months ago a major study called ASCEND was published that failed to find any benefit of omega-3s at reducing heart disease risk. The headlines said “Omega-3 Supplements Don’t Protect Against Heart Disease”. You were told that omega-3 supplements were worthless. I pointed out the weakness of that study in a previous issue of “Health Tips From the Professor”.

In mid-November two more major clinical studies were published. However, if you rely on the media for your information on supplementation, you are probably still confused. Headlines ranged from “Omega-3 Supplements Do Not Prevent Cancer Or Heart Disease” to “Eating More Fish Or Taking Omega-3 Fish Oil Supplements Can Cut Heart Attack Risk.” What is the truth?

Note: One of the clinical studies looked at the effect of omega-3s on both cancer and heart disease risk. I will discuss the cancer results briefly, but most of my focus will be on the heart disease findings.

How Were The Studies Designed?

The VITAL STUDY (JE Manson et al, New England Journal of Medicine, DOI: 10.1056/NEJMoa1811403 )in the United States. The study participants were 50% female, 50% male, and 20% African American. None of the participants had pre-existing heart disease. The characteristics of the study group were typical of the American population at that age, namely:

The average BMI was 28, which means that most of the participants were significantly overweight.
7% of them had diabetes.
38% were on cholesterol-lowering medications.
50% had high blood pressure treated by medication.

Study participants were given questionnaires on enrollment to assess clinical and lifestyle factors including dietary intake. Blood samples were taken from about 50% of the participants to determine omega-3 index at baseline and at the end of the first year. The participants were given a high purity omega-3 supplement (1 gram capsules containing 840 mg of total omega-3s, 460 mg of EPA, and 380 mg of DHA as the ethyl esters) or a placebo and followed for an average of 5.3 years.

There were two important characteristics of this study that distinguished it from the negative ASCEND study.

This study specifically excluded cardiovascular drugs other than statins and blood pressure medications because many of those drugs provide the same benefits as omega-3s. Patients in the ASCEND study were on 3-5 heart medications
The omega-3 status of participants at the beginning of this study was very low. The omega-3 status of participants in the ASCEND study was near optimal at the beginning of the study.

The REDUCE-IT study (DL Bhatt et al, New England Journal Of Medicine, DOI:10.1056/NEJMoa1812792 ): This study enrolled 8,179 participants (average age = 64) from several countries. The study participants were 70% male and 90% white. The average BMI was 31, which is considered obese. This study differed from the VITAL study in that all the patients were at high risk of heart disease.

70% of them had preexisting heart disease.
The remaining 30% had diabetes plus at least one additional risk factor for heart disease.
In addition, all of them had elevated triglycerides, which is an independent risk factor for heart disease.

The participants were given a high purity EPA supplement (4 grams of EPA as the ethyl ester) or a placebo and followed for an average of 4.9 years.

Do Omega-3s Reduce The Risk Of Heart Disease?

The VITAL Study: The primary end point for this study was something called “major cardiovascular events”, which was a composite every cardiovascular end point measured in the study. For this end point the results were negative. Omega-3 supplementation did not cause a significant decrease in major cardiovascular events compared to the placebo.

This was the result that was reported in the abstract and was what lazy journalists, who never read past the abstract, reported.

However, the rest of the study was very positive. For example, major cardiovascular events were reduced by:

26% in African-Americans.
26% in patients with diabetes.
17% in patients with a family history of heart disease.
19% in patients with two or more risk factors for heart disease.
19% in patients with low fish intake.

In other words, omega-3 supplementation caused a significant decrease in heart disease risk for high risk patients and for patients with a poor diet (low intake of omega-3s).

In addition, several individual cardiovascular events were significantly reduced by omega-3 supplementation. For example:

Heart attacks were reduced by 28% in the general population and by 70% for African-Americans.
Death from heart attacks was reduced by 50%.
Total coronary heart disease was reduced by 17%.
Death from coronary heart disease was reduced by 24%.

In short, headlines saying that omega-3 supplementation can decrease heart attack risk appear to be accurate. Saying that eating more fish can reduce heart attack risk is stretching it a bit. The study was not done with fish, and you would need to eat 2-4 servings of omega-3-rich fish a week to get an equivalent amount of omega-3s. That’s a lot of fish.

The authors attributed the positive results obtained in this study compared to the negative results obtained in several recent studies to four factors:

Many of the previous studies had fewer participants, used lower doses of omega-3s, and were shorter. There may not have been enough statistical power to demonstrate a benefit of omega-3s in those studies.
Participants in many of the previous studies were on multiple medications that mimicked the beneficial effects of omega-3s, making it more difficult to show a positive effect of omega-3 supplementation.
Most of the previous studies either did not measure the omega-3 status of participants or had a study population that started the study with near optimal omega-3 status. The VITAL study showed that omega-3s had a stronger beneficial effect for people who seldom ate fish.
African-Americans were underrepresented in most previous studies. The VITAL study showed that omega-3s were more beneficial for African-Americans than for other ethnic groups.

As for side effects, there was no increased risk of bleeding or any other serious side effect from omega-3 supplementation.

The REDUCE-IT Study: This study of high-risk patients was even more positive than the VITAL study.

The composite of all cardiovascular end points was reduced by 25%.
The risk reduction was greatest for men, non-whites, and people over 65.
The risk reduction was also greatest for people with pre-existing heart disease, very high triglyceride levels, and people who required high-dose statin therapy to keep their cholesterol under control.

In other words, everyone benefited from omega-3 supplementation in this study because they were all at high risk, but those at the highest risk benefitted the most.

When they looked at individual cardiovascular events:

Fatal and non-fatal heart attacks were reduced by 31%.
Cardiovascular death was reduced by 20% and death from any cause was reduced by 23%.
Fatal and non-fatal stroke was reduced by 28%.
Hospitalization for unstable angina was reduce by 32%.

However, this very high dose of EPA was not completely without risk:

1% of patients in the EPA group were hospitalized for atrial fibrillation versus 2.1% in the placebo group.
7% of patients in the EPA group experienced a serious bleeding event compared to 2.1% in the placebo group.

Do Omega-3s Reduce The Risk Of Cancer?

The VITAL Study: The VITAL study also looked at the effect of omega-3s on cancer risk. The results from this study were uniformly negative. There was no effect of omega-3 supplementation on invasive cancer of any type, breast cancer, prostate cancer, colon cancer, or death from cancer. Does that mean omega-3s have no role in reducing cancer risk? That’s not clear.

If we look at previous animal studies and human association studies, reduced cancer risk is seen when omega-3s replaced saturated fats, trans fats, and/or omega-6 fats in the diet. The subjects in the VITAL study ate a typical American diet, and the study made no effort to change what they were eating. It just added an omega-3 supplement. There is relatively little evidence that you can eat burgers and fries and expect omega-3s to reduce cancer risk.

The VITAL study merely confirms what previous studies have suggested. You can’t continue to eat a typical American diet and expect omega-3s to make cancer go away. Omega-3s should be thought of as part of a holistic approach to reducing cancer risk. If they have any role in reducing cancer risk, it is likely to be as part of a primarily plant-based diet that substitutes omega-3s for the bad fats in the American diet.

For example, the Mediterranean diet is primarily plant-based and is rich in healthy oils like olive oil and omega-3s. It is associated with reduced risk of several cancers, especially cancers of the breast and colon.

Are Omega-3 Supplements Good For You?

There is a lot of confusion around the question of whether omega-3s are good for the heart. Some studies say yes. Others say no. If you average all the studies together, as some recent meta-analyses have done, it is easy to throw up your hands and conclude there is no definitive evidence that omega-3s reduce heart disease risk. However, if you look at why the studies differ a clear pattern emerges.

If the study subjects are on multiple heart medications that duplicate the beneficial effects of omega-3s, the studies tend to be negative. If the subjects are only on one or two medications, the studies tend to be positive. Since most people I know would prefer to minimize the number of medications they are on, the negative studies with multiple medications are simply not relevant to them.
If the study subjects are at low risk of heart disease, the studies tend to be negative. If the subjects are at high risk, the studies tend to be positive. This does not mean that omega-3s are of no benefit if you are at low risk of heart disease. It simply reflects the fact it is easier to show a beneficial effect of any intervention when you have a pool of high-risk patients who are likely to experience some sort of cardiovascular event during the time-period of the study.

For example, as discussed in my recent book, “Slaying The Supplement Myths,” this the same pattern you see with statin clinical studies. If patients are at high risk, statin drugs clearly save lives. If they are at low risk, it is almost impossible to show any benefit of statin drugs. Cardiologists extrapolate from the high-risk studies and prescribe statins to low-risk patients. I think it is time to take a similar approach with omega-3s.

If the subjects have a good omega-3 status at the beginning of the study, additional omega-3 supplementation usually has no benefit. If their omega-3 status is poor at the beginning of the study, the results of omega-3 supplementation tend to be positive. This is just common sense. Supplementation is meant to fill gaps in the diet – not to provide a surplus of nutrients. Of course, the reality is many Americans do not get enough omega-3s in their diet.

What Do These Studies Mean For You?

Omega-3s Are Good For Your Heart: When you combine the latest studies with what we already know about omega-3s and heart disease, the results are clear-cut.

If you are at high risk of heart disease, don’t eat many omega-3-rich fish, and/or don’t want to be on a handful of heart medications, the evidence is strong that omega-3s reduce your risk of heart disease.
On the other hand, if you are at low risk of heart disease, eat 2-4 servings of omega-3-rich fish a week, and/or are happy taking multiple heart medications with all their side effects, it is difficult to prove that omega-3s have any benefits. That doesn’t mean that omega-3s don’t have benefits. It just means we can’t prove they do.

If you are still having trouble making up your mind whether omega-3 supplements are the right choice for you, I might remind you:

If you are like millions of Americans, the first sign you are at risk of heart disease might be sudden death.
If you are like most Americans, you are probably not getting enough omega-3s in your diet.
If you prefer taking drugs, you are probably not interested in supplements anyway.

Holistic Is Best: When you combine the VITAL study results with what we already know about omega-3s and cancer, it appears that adding omega-3s to a bad diet is unlikely to reduce your risk of cancer. However, a holistic approach that starts with a healthy, primarily plant-based diet and substitutes omega-3s for the bad fats in the American diet is likely to substantially reduce your cancer risk. The Mediterranean diet might be considered an example of that approach.

The same is likely true for heart health. While the latest two studies suggest that adding omega-3 supplements to your regular diet reduces your heart disease risk, those omega-3 supplements are likely to be even more effective if you also adopt a heart-healthy diet and lifestyle.

Omega-3 Supplements vs Omega-3 Drugs: The Omega-3 preparations used in this study are pharmaceutical-grade omega-3 preparations and are marketed as drugs. Thus, it is likely that many doctors will recommend them rather than less expensive omega-3 supplements. Which choice is best for you?

The preparation used in the VITAL study is similar in composition to many commercially available omega-3 supplements. The main difference is that it is high purity and is subject to the quality control standards required for pharmaceutical drugs. Many omega-3 supplements do not meet these standards, but some do. If you wish to use an omega-3 supplement, do your research. Inquire about their quality control standards and only buy high purity supplements.

The preparation used in the REDUCE-IT study used ultra-pure EPA only. That preparation did not contain any other omega-3s, so a commercially available omega-3 supplement would not be comparable. However, I do not recommend an EPA-only supplement for three reasons.

The results for high risk patients in the REDUCE-IT study were similar to those for high risk patients in the VITAL study. This suggests that removing DHA and other omega-3s may not provide additional protection against heart disease. A head to head comparison of the two supplements would be required to prove the superiority of an EPA-only supplement.
I have the same concern for this high-dose EPA supplement as I have for any high-dose single nutrient supplement. DHA and other omega-3s provide benefits such as cognitive health that EPA does not. Very high dose EPA is likely to interfere with the uptake and utilization of the other omega-3s.
The EPA only supplement used in the REDUCE-IT study had side effects that were not seen with the mixed omega-3 supplement used in the VITAL study. It is not clear whether those side effects were due to differences in dose or differences in formulation.

Omega-3 Ethyl Esters vs Omega-3 Triglycerides: There has been a lot of hype about the superiority of omega-3 triglyceride preparations recently. These studies were both done with omega-3 ethyl esters and proved to be very effective. Until someone shows that omega-3 triglyceride preparations provide better results at reducing heart disease risk than omega-3 ethyl esters, I would leave omega-3 triglyceride supplements on the shelf.

How Much Omega-3s Do You Need? We have too few dose-response studies to reliably predict how much omega-3s are optimal for reducing heart disease risk. The 1 gram/day dose used in the VITAL study gave good results, so that is an excellent starting point. The 4 gram/day dose used in the REDUCE-IT study seemed to provide little additional benefit.

Of course, the optimal dose is likely to be different for each of us. Once the omega-3 index blood test becomes more widely available I would recommend getting your omega-3 index determined on an annual basis and aiming for an omega-3 index of 8 or above, since that is the level associated with a low risk of heart disease.

The Bottom Line

However, two recent studies support the effectiveness of omega-3s for reducing heart disease risk. When you combine the latest studies with what we already know about omega-3s and heart disease, the results are clear-cut.

If you are at high risk of heart disease, don’t eat many omega-3-rich fish, and/or don’t want to be on a handful of heart medications, the evidence is strong that omega-3s reduce your risk of heart disease.
On the other hand, if you are at low risk of heart disease, eat 2-4 servings of omega-3-rich fish a week, and/or are happy taking multiple heart medications with all their side effects, it is difficult to prove that omega-3s have any benefits. That doesn’t mean that omega-3s don’t have benefits. It just means we can’t prove they do.

If you are still having trouble making up your mind whether omega-3 supplements are the right choice for you, I might remind you:

If you are like millions of Americans, the first sign you are at risk of heart disease might be sudden death.
If you are like most Americans, you are probably not getting enough omega-3s in your diet.
If you prefer taking drugs, you are probably not interested in supplements anyway.

In addition, one of the studies confirmed what we already know about omega-3s and cancer. Adding omega-3s to a bad diet is unlikely to reduce your risk of cancer. However, a holistic approach that starts with a healthy, primarily plant-based diet and substitutes omega-3s for the bad fats in the American diet is likely to substantially reduce your cancer risk. The Mediterranean diet might be considered an example of that approach.

For more details read the article above. In addition, the article covers topics like omega-3 supplements versus omega-3 drugs, omega-3 ethyl esters versus omega-3 triglycerides, and how much omega-3s we need. It also discusses why several recent studies have failed to find a benefit of omega-3s for reducing heart disease risk.

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

Do Organic Foods Decrease Cancer Risk?

November 27, 2018 by Dr. Steve Chaney

Is Eating Organic Worth The Cost?

Author: Dr. Stephen Chaney

Millions of Americans choose organic foods whenever possible. However, organic foods are expensive, and some experts claim they are a waste of money. That is why recent headlines claiming that eating organic foods decrease cancer risk have created such a stir. I will look at the study behind the headlines below, but first let me summarize what we do know about organic foods.

I discussed a study comparing organic and conventionally-grown produce in a recent issue, Organic Foods Healthier, of “Health Tips From the Professor”. It was a major study that combined the results from 343 of the best-designed previous studies. The study found that pesticide and herbicide residues were 4-fold lower in organically-raised produce than in conventionally-raised produce. It also found that the polyphenol content of organically-raised produce was slightly higher than in conventionally-raised produce.

Neither of these findings automatically mean that eating organic produce will improve your health. However, there is increasing evidence that pesticide exposure is linked to increased risk of cancer. Thus, it seems logical that eating organic might decrease cancer risk. It is that hypothesis that the current study (J Baudry et al, JAMA Internal Medicine, doi: 10.1001/jamainternmed.2018.4357 ) was designed to test.

How Was The Study Designed?

This study is part of a major French study called NutriNet-Santé that was launched in 2009. The NutriNet-Santé study is web-based study designed to investigate associations between nutrition and health.Volunteers with access to the internet were recruited from the general population. After agreeing to participate in the study, the volunteers were asked to complete a battery of online assessment forms.

The baseline data for the NutriNet-Santé study included age, sex, occupational status, education level, marital status, income, number of children, smoking status, physical activity, and diet. Dietary intake was assessed using three 24-hour dietary recalls collected over a 2-week period. Two of the 24-hour dietary recalls were on weekdays and one was on a weekend.

The dietary recalls were used to create a “score” of diet quality. Without going into detail, diets that favored animal protein, animal fats, sweets, and highly processed foods were considered “poor quality diets.” Diets that favored plant proteins, vegetable oils & and omega-3 fats, fruits, vegetables, and whole grains were considered “good quality diets.”

This portion of the NutriNet-Santé was designed to measure the correlation between organic food consumption and cancer risk. Two months after enrollment in the study, the participants were asked to provide information on the frequency with which they chose the organic version of 16 different types of food. From this information each participant was assigned an “organic food score” ranging from 0 to 32 points.

The participants in this study were also asked to complete a yearly health status questionnaire online. If they reported a cancer diagnosis, they were asked to provide their medical records, and the study physicians contacted the patient’s physician to confirm details of the diagnosis.

A total of 68,946 French adults completed the study (78% female, mean age 44.2 years). They were followed for an average of 4.56 years. During this time period there were 1340 new cancer diagnoses in this population.

Do Organic Foods Decrease Cancer Risk?

The participants were divided into four groups based on their organic food score. When participants with the highest organic food score were compared to those with the lowest organic food score there was a:

25% reduction in total cancer risk.
86% reduction in non-Hodgkin lymphoma risk. This is not a novel finding. A previous study has also suggested eating organic might reduce the risk of non-Hodgkin lymphoma.
76% reduction in all lymphoma risk.
34% reduction in postmenopausal breast cancer risk.

The authors concluded “A higher frequency of organic food consumption was associated with a reduced risk of cancer. Although the study findings need to be confirmed, promoting organic food consumption in the general population could be a promising preventive strategy against cancer.”

These are the results and conclusions that made the headlines. However, the scientists who designed the study were aware of previous data showing that people who eat organic are also more likely to eat a healthy diet and follow a healthy lifestyle. Thus, their statistical analysis of the data considered all factors that might influence cancer risk. This analysis provided a much more nuanced interpretation of the data. They found that the association between increased organic food consumption and decreased cancer risk:

Was significant for women, older adults, individuals with a family history of cancer, individuals who had a poor diet, and former smokers.
Was seen for people of all weights but was greatest for individuals who were obese.
Was non-significant for men, younger adults, individuals with no family history of cancer, individuals who had a good diet, never-smokers, and current smokers.
Was non-significant for other types of cancer.

You are probably wondering “Does this mean organic foods are beneficial for some people, but not for others?” A superficial interpretation of these data might lead to that conclusion, but let’s dig a little deeper.

What Does This Study Mean For You?

In interpreting a study of this type, it is important to ask whether enough people will develop cancer during the study for the results to be statistically significant. That depends on 3 factors:

The number of people enrolled in the study.
The duration of the study.
The probability that participants will develop cancer during the duration of the study.

When you look at the whole study population, all three criteria have been met. There were 68,949 participants who were followed for 4.56 years. During that time 1340 of them developed cancer, of which 459 were breast cancer, 47 were non-Hodgkin lymphomas, and 15 were other lymphomas. A higher frequency of organic food consumption was associated with a decreased in the risk of all these cancers, and that decreased risk was statistically significant. This is the main take-home lesson of the study.

However, when you start to break the study down into subgroups, the number of people in each subgroup and the duration of the study become limiting factors. For example:

We don’t really know whether eating organic foods are unimportant for men or whether there were too few men in the study for any benefit to be statistically significant.
Colon cancer and many other cancers develop gradually over a 10 to 20-year period. We don’t know whether choosing organic foods is unimportant for these cancers or whether 4.56 years is too short a time to show a significant benefit.
The same is true for several of the other variables in this study. For example, if you are an older adult, have a family history of cancer, have a bad diet, and/or have smoked in the recent past, your probability of developing cancer over a 4.56-year time period is relatively high. On the other hand, if you are younger, have no family history of cancer, have a good diet, and have never smoked, your probability of developing cancer during that same time period is very low.

So, how do we interpret the data with these subgroups? We could conclude that eating organic foods in unimportant for people who are young, have no family history of cancer, have a good diet, and have never smoked. A more likely interpretation, however, is that people in these groups have such a low risk of cancer that 4.56 years is too short to demonstrate a benefit of organic foods. It might require a 10, 20, or 30-year study to show benefit of organic foods for these people.

Let me close with three important observations:

People often say too me: “I can’t afford organic fruits and vegetables, but I am concerned about pesticide exposure. Does that mean I should avoid fruits and vegetables?” The data from this study provide a clear answer. Eating lots of fruits and vegetables is beneficial even if you can’t afford organic.

[I also let them know about “The Dirty Dozen” ( Rank Produce Items By Pesticide Level ). This is a list of the fruits and vegetables most likely to be contaminated with pesticides. If your budget for organic foods is limited, these are the most important fruits and vegetables to spend it on.]

I find it ironic that people who consume a poor diet are the ones most likely to experience an immediate benefit from choosing organic foods. This is, of course, the group that is least likely to eat organic.
If you smoke, eating organic probably isn’t going to help you much. Your best bet is to stop smoking.

The Bottom Line

A recent study looked at the association between organic food consumption and cancer risk. When participants who consumed organic foods frequently were compared to those who almost never consumed organic foods there was a:

25% reduction in total cancer risk.
86% reduction in non-Hodgkin lymphoma risk. This is not novel. A previous study has also suggested eating organic might reduce the risk of non-Hodgkin lymphoma.
76% reduction in all lymphoma risk.
34% reduction in postmenopausal breast cancer risk.

These are the results and conclusions that you have seen in the headlines. However, the scientists who designed the study were aware of previous data showing that people who eat organic are also more likely to eat a healthy diet and follow a healthy lifestyle. Thus, their statistical analysis of the data considered all factors that might influence cancer risk. This analysis provided a much more nuanced interpretation of the data, which I have discussed in the article above.

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.