Does An Apple A Day Keep Statins Away?

The Latest On Diet And Heart Health

Author: Dr. Stephen Chaney

AppleIn a previous “Health Tips From the Professor” I talked about how difficult it has been to prove that statins significantly reduce the risk of heart attack or cardiovascular deaths in a low risk population group. Now let’s look at the other side of the coin – lifestyle change –and ask how effective lifestyle change is at reducing the risk of cardiovascular disease.

You’ve all heard the saying “An apple a day keeps the doctor away”. It dates back to Victorian England. It was the public health message of the day – much simpler and more concise than our current food guide plate.

A prominent British doctor and his research team recently decided to see how accurate that saying really was. But they took their study one step further. They compared the effectiveness of an apple a day versus a statin a day at reducing the risk of cardiovascular deaths (Briggs et al, British Medical Journal, 3013;347:f7267 doi: 10.1136/bmj.f7267).

The results of that comparison may surprise you.

Does An Apple A Day Keep Statins Away?

They used the data from the Cholesterol Treatment Trialist meta-analysis to estimate the effectiveness of statin drugs at reducing cardiovascular deaths. They used the data from the PRIME comparative risk assessment model to estimate the effectiveness of apple a day at reducing cardiovascular deaths.

They asked what would happen if each of them were the primary intervention for the entire British population over 50 who were not currently taking statin drugs (17.6 million people).

They assumed a 70% compliance rate for both interventions. In simple terms that means they assumed that 70% of the population would actually do what their doctors told them. (Patients must be more compliant in England than in the US).

The results were interesting. They estimated that:

  • Giving a statin drug each day to 17.6 million people would reduce the number of cardiovascular deaths by 9,400.
  • Giving an apple each day to the same 17.6 million people would reduce the number of cardiovascular deaths by 8,500 (not significantly different).

But when they looked at side effects and cost the two interventions were significantly different.

  • Giving a statin drug each day to 17.6 million people would also cause some significant side effects. The authors estimated that it would lead to:
    • 1,200 excess cases of severe muscle pain and weakness
    • 200 excess cases of rhabdomyolysis (muscle breakdown, which can lead to irreversible kidney failure)
    • 12,300 excess cases of diabetes
  • On the other hand, there are no known side effects to an apple a day.
  • The statin intervention would cost an estimated $295 million. In the case of apples, you would presumably be substituting a more healthy food for a less healthy food so there would be little or no net cost.

And the 70% compliance rate is probably wildly optimistic. Some experts have estimated that up to 50% of patients discontinue their statin medications within the first year because of side effects or cost.

Is There A Scientific Basis For Those Estimates?

Of course, we all know that the “apple a day…” saying was never meant to be taken literally. It was just a simple way of saying that a good diet will reduce the risk of disease.

It turns out that there was another major study on the effect of dietary fiber on reducing the risk of cardiovascular disease in the very same issue (Threapleton et al, British Medical Journal, 2013;347:f6879 doi: 10.1136/bmj.f6879). It was a meta-analysis that combined the data from 22 previously published studies.

This study showed:

  • For every 7 g/day increase in dietary fiber the risk of both heart attacks and cardiovascular disease decreases by 9% (7 grams of dietary fiber could come from one serving of whole grains plus one serving of beans or lentils or from two servings of fruits or vegetables).
  • For every 4g/day of fruit fiber (equivalent to one apple) the risk of heart attacks decreases by 8% and the risk of cardiovascular disease decreases by 4%.
  • The numbers are similar for every 4 g/day of vegetable fiber.

Another recent study showed that consumption of 75 g/day of dried apple (equivalent to two apples a day) lowered total cholesterol by 13% and LDL-cholesterol by 24% in post-menopausal women (Chai et al, J. Acad Nutr Diet, 112: 1158-1168, 2012). That’s comparable to the cholesterol reduction achieved with statin drugs.

The Bottom Line

  • If you have not previously had a heart attack and are at relatively low risk, something as simple as adding an apple a day (in place of less healthy foods) may just as effective as statin drugs at reducing your risk of cardiovascular death without the side effects and cost of the drugs.
  • This is not really new information. For years both the American Heart Association and the National Institutes of Health have recommended that Therapeutic Lifestyle Changes (weight loss, healthy diet and exercise) should be tried BEFORE drug treatment to reduce the risk of heart disease.
  • So if you want to avoid statins, tell your doctor that you are willing to make the needed lifestyle changes to reduce your risk of heart disease and stick with it. Lifestyle changes are hard, but clinical studies clearly show they can often be just as effective as drug therapy, without the cost and side effects.
  • Don’t misunderstand me. I’m not advocating avoiding statin drugs if they are absolutely necessary. If you have had a heart attack or are at high risk of heart disease, it is clear that statins can save lives. Even here I would recommend talking with your physician about incorporating therapeutic lifestyle change into your regimen. It may allow them to minimize the dose, and therefore the side effects, of the statin drugs.

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 Causes Food Cravings?

Is Your Body Trying To Tell You Something?

Author: Dr. Pierre DuBois

What Causes Food Cravings?

food cravingsFor some years, researchers had believed that having cravings for a particular type of food may be an indication that you are missing a particular nutrient in your diet. For example, if you crave red meat then you may have an iron deficiency, or if you crave ice cream you must need calcium.

Studies have shown, however, that cravings have nothing to do with a nutritional deficiency, but are actually caused by chemical signals in the brain. Nutritionist Karen Ansel says, “If cravings were an indicator of nutritional deficiency, we’d all crave fruits and vegetables. The fact that we all want high carb, high fat comfort foods, along with the research, is a pretty good indicator that cravings aren’t related to deficiencies.” Yes–it’s really all in your head.

Fat, Sugar and Salt Fuel Food Cravings

When you crave a food, the same reward centers in the brain that are responsible for drug and alcohol addiction are more active: the hippocampus (memory), the insula (emotion and perception) and the caudate (memory and learning). These areas are all very receptive to dopamine and serotonin, neurotransmitters that are responsible for feeling relaxed and calm and which spur reward-driven learning.

The reason you crave things such as ice cream, potato chips and chocolate is that these items are full of fat, sugar and/or salt. Both fat and sugar are involved in an increased production of serotonin and other chemicals that make us feel good.

Food Cravings Are Also Learned

There is a large societal aspect to cravings as well. For instance, women in Japan tend to crave sushi and only 6 percent of Egyptian women say they crave chocolate. Approximately half of American women claim that their cravings for chocolate reach a peak just before their period. However, research has found no correlation between fluctuations in women’s hormones and cravings. In fact, postmenopausal women do not report a large reduction in cravings from their premenopausal levels.

Will Power Alone Is Not Enough

Studies have found that the more people try to deny their cravings, the greater the craving they have for the forbidden food. Researchers suggest that it is better to give in to the craving in a controlled way rather than denying yourself altogether. Just be sure to restrict what you consume to a reasonable amount. If your dopamine receptors are constantly bombarded with high-fat and high-sugar foods (or drugs and alcohol), they shut down to prevent an overload. This makes your cravings even greater and you end up eating more in an attempt get the same reward, but you never really feel satisfied.

How To Bust Your Food Cravings

Exercise and distraction are the two best ways to reduce food cravings. One study found that a morning workout can reduce your cravings for the whole day. Other studies suggest that distracting your mind with other pleasurable stimuli can be effective. For example, smelling a non-food item that you really like can also help. Keep a small vial of your favorite perfume with you when a craving comes on and take a whiff when the craving hits you. It will occupy the aroma receptors that are involved in food cravings.

The Bottom Line

  • In most cases food cravings are not due to nutritional deficiencies. They are a physiological response of the “pleasure center” in the brain to fat, sugar & salt.
  • Food cravings are different in different cultures, which indicates that food cravings are also a learned response.
  • Willpower alone is not sufficient to overcome food cravings.
  • The best strategy to avoid food cravings is to exercise regularly and distract your attention with other pleasurable stimuli.

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.

Omega-3 Fatty Acids And Brain Health

Is it How Much You Eat, or How Much You Keep?

Author: Dr. Stephen Chaney

 

Brain HealthWhy do some studies conclude that omega-3 fatty acids are essential for a strong mind, a strong heart and will wipe out inflammation – while other studies suggest that they are ineffective? The simple answer is that nobody really knows.

However, in the process of reviewing two recent studies on omega-3 fatty acids and brain health I made an interesting observation that offers a possible explanation for the discrepancies between studies. And if my hypothesis is correct, it suggests that the design of many of the previous studies with omega-3 fatty acids is faulty.

Omega-3 Fatty Acids And Brain Health

The first study (J.K. Virtanen et al, J Am Heart Assoc, 2013, 2:e000305 doi: 10.1161/JAHA.113.000305) looked at the effect of omega-3 fatty acids on brain function in older adults (>65 years old). It concluded that high omega-3 levels were associated with better white matter grade and a 40% reduction in subclinical infarcts (Sorry for the technical jargon – but both of those are good things in terms of brain function for those of us who are getting a bit older).

The second study (C. M. Milte et al, J of Attention Disorders, 2013, doi: 10.1177/1087054713510562) looked at the effect of omega-3 fatty acids on children (ages 6-13) with ADHD. It concluded that high omega-3 levels were associated with improved spelling and attention and reduced oppositional behavior, hyperactivity, cognitive problems and inattention.

What Is The Common Thread In These Studies?

Why, you might ask, am I comparing a study in the elderly, where the concern is retention of cognitive skills, with a study on ADHD in children?

That’s because there is a very important common thread in those two studies. It wasn’t the amount of omega-3 fatty acids in their diet that counted. It was the levels of omega-3 fatty acids in their blood that made the difference.

The first study included a detailed dietary history to estimate the habitual intake of omega-3 fatty acids in the participants.

  • There was no correlation between estimated dietary intake of omega-3 fatty acids and any measure of brain function in those older adults.
  • However, there was a strong correlation between blood levels of omega-3s and brain health in that population group.

The second study was actually a placebo controlled intervention study in which the children were given 1 gm/day of either omega-3 fatty acids or omega-6 fatty acids.

  • Once again, there was no correlation between dietary intake of omega-3 or omega-6 fatty acids and any outcome related to ADHD.
  • However, there was a strong correlation between blood levels of omega-3 fatty acids or omega-3/omega-6 ratio and improvement in multiple measures of ADHD.

How Could The Effect of Dietary Intake And Blood Levels Of Omega-3s Be So Different?

Fish OilBoth studies were relatively small and suffered from some technical limitations, but the most likely explanations are:

  • Inaccurate recall of the participants as to what they eat on a habitual basis. (study 1)
  • Individual differences in the ability of participants to convert short chain omega-3 fatty acids (found in foods such as canola oil, flaxseed oil and walnuts) to the beneficial long chain fatty acids (found in cold water fish). (study 1)
  • Poor compliance in taking the supplements. (study 2)

Why Are These Studies Important?

The most important insight to come out of both of these studies is that it is essential to actually measure blood levels of omega-3 fatty acids and not just rely on dietary intake or supplementation for a valid clinical trial.

That’s a concern because blood measurements of omega-3 fatty acids are expensive and have not been a part of many of the clinical studies that have been performed to date. Even the largest, best designed clinical study is worthless if the dietary recalls aren’t accurate or people don’t take their capsules.

We need to go back and reevaluate many of the clinical studies that have been published.

We need to ask:

  • Are their conclusions valid?
  • Did some studies fail to show that omega-3s were effective simply because they only measured dietary intake and not how much of the omega-3s actually accumulated in the blood?

The Bottom Line

  • High blood levels of omega-3s in the blood correlated with improved brain health in the elderly and reduced ADHD symptoms in children
  • These studies were small, but they are consistent with a number of other studies that have come to similar conclusions.
  • Blood levels of omega-3s are better predictors than dietary intake for evaluating the health benefits of omega-3 fatty acids.
  • Many previous studies that failed to find an effect of omega-3 fatty acids on brain health, heart health or inflammation did not actually measure blood levels of the omega-3 fatty acids. These studies should be reevaluated.

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.

Healthy Thanksgiving

Author: Dr. Stephen Chaney

Healthy ThanksgivingWhile “Healthy Thanksgiving” doesn’t quite have the appeal of the more familiar “Happy Thanksgiving” greeting, I used it here to make the point that Thanksgiving dinner (and many other holiday meals) doesn’t have to be an unhealthy affair.

After all, there is a lot to like about the ingredients in Thanksgiving dinner.  Turkey can be a healthy, low- fat meat, if prepared correctly.  Sweet potatoes, yams, winter squash and pumpkin are all loaded with vitamin A and other important nutrients.  And cranberries are a nutrition powerhouse.

Healthy Thanksgiving

Here are some tips to make your Thanksgiving meal one that contributes to your health:

1) Skip the basting.  Choose a plain bird and cook in a bag to seal in the moisture.  Remove the skin before serving.

2) Refrigerate the turkey juices and skim off the hardened fat before making gravy and use a gravy cup that pours from the bottom to minimize fat.

3) Use ingredients like whole wheat bread, vegetables, fruits (cranberries, raisins, dates or apples), nuts and your favorite spices for the stuffing and bake it in the oven rather than in the turkey.

4) Serve your sweet potatoes or yams baked rather than candied and let your guests add butter to taste.

5) Use skim milk or buttermilk rather than whole milk and skip the butter for your mashed potatoes.

6) Give your meal gourmet appeal by cooking your green vegetables with garlic, nuts and herbs rather than creamy or fat-laden sauces.

7) Don’t serve the meal on your largest plates. By using smaller plates you ensure smaller portion size and even that second helping isn’t quite so damaging.

8) Use the Shaklee 180 meal replacement products for one or more meals the day before and/or after Thanksgiving so that your total caloric intake over the three day period is not excessive.

By now you have the idea.  There are lots of little things that you can do to make your Thanksgiving dinner one that your waist and your heart will thank you for. Bon Appetit and have a Happy, Healthy Thanksgiving!

The Bottom Line

  • If you make healthy food choices and choose your portion sizes wisely, you can make this a healthy Thanksgiving as well as a Happy Thanksgiving.

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.

Should GMO Labeling Be Required For All Food Ingredients?

When Is GMO Not GMO?

Author: Dr. Stephen Chaney

GMO-freeI’m probably going to get lots of hate mail for this week’s “Health Tips from the Professor” because I’m finally going to tackle the GMO controversy.

You see, the GMO controversy is very much like Washington politics. On one side of the aisle, you have the people who are absolutely convinced that anything GMO is terrible. On the other side of the aisle, you have people who are absolutely convinced that there are no problems with GMO foods. And both sides are convinced that their opponents have absolutely nothing of intelligence to say on the topic.

So almost anything I say about GMO is bound to offend somebody. But nobody ever accused me of being timid, so let’s get started.

What Are The Health Risks Of Genetically Modified Foods?

I’m going to start with the supposed health risks of GMO foods because that’s my area of greatest expertise, and I’m going to evaluate those health risks from the viewpoint of a card-carrying biochemist. I’ve seen the scary pictures and alarming statements posted on many anti-GMO web sites, but objective evidence that genetically modified foods are harmful to humans is underwhelming at present.

Modifications to DNA And Health Risks

Let’s start at the beginning. Genetic modification occurs in the DNA, and on that basis GMO foods have some potential, but yet unproven, risks. Let me give you an example:

  • Some genetically modified foods carry genes for naturally occurring pesticides so that if bugs try to eat the leaves of those plants they will die.
  • When we eat foods occasionally small pieces of their DNA will find their way into our intestinal track.
  • We have bacteria in our intestinal tracts that excel at picking up small pieces of DNA and inserting them into their genome.
  • So it is theoretically possible that those bacteria might start producing in our intestines the same pesticides produced by the genetically modified foods we ate.

It is an interesting idea, but to my knowledge one that has not yet been shown to have actually occurred in a human being.

Modifications to Proteins And Health Risks

A more likely risk comes from the proteins contained in genetically modified foods:

  • Genetic modifications in the DNA result in the production of modified proteins, so GMO foods, GMO protein powders and foods made from GMO protein sources can be a source of unsuspected food allergies.
  • Unfortunately, food allergies, especially those from genetically modified protein sources, are very difficult to quantify, so we have no good data on how big a problem this actually is.

However, it would be very surprising if there weren’t some individuals with food allergies to genetically modified proteins.

When Is GMO Not GMO?

Many of the GMO opponents take it one step further and want to label as GMO any food or supplement that contains any ingredient made from a genetically modified food. This is where the science is clearly on the other side of the aisle. With respect to purified sugars, purified oils, vitamins and other purified nutrients obtained from foods there is no difference between GMO and non-GMO because these purified nutrients contain neither DNA nor protein.

 Should GMO Labeling Be Required For All Food Ingredients?

For the most part, it isn’t even possible for most manufacturers to produce foods or supplements with all non-GMO ingredients. When the whole GMO issue first entered public awareness the food industry was guided by the science. It made good business sense for them to create a capacity, a pipeline if you will, to make sure that non-GMO protein sources were available to meet the market demand for companies that wanted to make non-GMO protein products for this new GMO-adverse market.

But, nobody anticipated the emotional demand for non-GMO sugars, oils and the like. There was no scientific basis for that demand, so none of the suppliers created the capacity to meet that demand. Currently there is only enough of those kinds of non-GMO ingredients to meet the needs of the bit players in the market. There simply aren’t enough of those ingredients to satisfy the requirements of any manufacturer who deals in the mass market. That, for example, is the reason big players in the market lobbied against the recent California and Washington State propositions that would have required a food product to be labeled GMO if any ingredient in the food was GMO.

Genetically Modified Foods And The Environment

Now that I have managed to alienate almost everyone, I should point out that there are some non-health issues around GMO foods.

  • The biggest issue is that many of the genetically modified foods contain modifications that make them resistant to herbicides, and that encourages overuse of those herbicides with the resultant pollution of air, soil, and water.
  • Another concern is that the increasing reliance on genetically modified food crops is leading to a decrease in the genetic diversity of those crops, which could make them more susceptible to a new virus or pest in the future. This is a theoretical concern, but there is historical precedence for believing that it could happen.
  • Finally, laws that prevent subsistent farmers from saving their own seed for next season’s planting is a major concern in Third World countries. But, that is more an issue of corporate greed than it is of genetic modification.

The Bottom Line:

What is the take-home lesson for you?

From a health perspective:

  • Genetically modified proteins are likely to be a food allergy risk for some people, but we have no good data on how many people are affected by this kind of food allergy
  • Genetically modified DNA is a theoretical concern because of the ability of intestinal bacteria to pick up pieces of DNA, but we have no evidence at present that this has actually ever caused a problem in people.
  • With respect to sugars, oils, and other nutrients extracted from foods it makes no difference whether the food was GMO or non-GMO

From an environmental perspective:

  • Genetic modifications leading to herbicide resistance are a significant environmental concern because it encourages overuse of herbicides.
  • Lack of genetic diversity from the overuse of GMO food crops is a theoretical concern, but one with historical precedence.

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 Dietary Polyphenols Associated With Longevity?

Are Polyphenols The Fountain of Youth?

Author: Dr. Stephen Chaney

Merlot Grapes HDRYou’ve probably heard that resveratrol and other polyphenols in red wine can help mice live longer. But what about us? Are dietary polyphenols associated with longevity in humans?

Until recently nobody knew the answer to that question. However, a recent study (Zamora-Ros et al, J. Nutr. 143: 1445-1450, 2013) suggests that polyphenols may just help us live a bit longer.

Of course, the news headlines make it sound like a sure thing, and many of the manufacturers of polyphenol-containing supplements are already citing the study as “proof” that their products will make you live forever.

Polyphenols Are Everywhere:

So, let me give you some background information before I start diving into the study.

  • The term polyphenols includes some names you may recognize, such as flavonoids, isoflavones, anthrocyanidins and resveratrol, and many more that might look like the kind of names you might expect to find on a processed food label.
  • Polyphenols don’t just come from red wine. There are several hundred polyphenols in edible foods. Many fruits, vegetables (including beans like soybeans) and whole grains – the kinds of foods that every expert recommends for a healthy diet – are also great sources of polyphenols.
  • Most polyphenols are excellent antioxidants. Studies suggest that they may also exert antiinflammatory effects and may reduce the risk of heart disease, neurodegenerative disease and cancer. So it is not unreasonable to assume that they might enhance longevity.

An In-Depth Analysis Of The Study:

The study enrolled 807 men and women over the age of 65 (average age = 74, range = 67-81) from the Chianti region of Italy and followed them for 12 years. At the beginning of the study polyphenol intake of the participants was analyzed from a dietary recall form (polyphenol intake based on what they remembered eating) and from a 24 hour urine specimen (actual polyphenol intake).

During the 12 year follow-up, 34% of the participants died. Based on the dietary recall, there was no association between dietary polyphenol intake and mortality. However, based on urinary polyphenol content there was a 30% decrease in mortality for those with the highest dietary polyphenol intake (>650 mg/day) compared to those with the lowest polyphenol intake (<500 mg/day).

Strengths of the Study:

  • This is the very first study to actually investigate the relationship between dietary polyphenols and longevity in a meaningful way. The study was well designed and well executed.
  • The measurement of urinary polyphenol content is a strength of this study. Dietary recalls are often inaccurate. In fact, this study suggests that dietary recalls should probably not be used to estimate dietary polyphenol intake in future studies.

Weaknesses of the Study:

  • This was a first study of its kind, and like any other first study it needs to be confirmed by additional studies.
  • The study only measured associations, not cause and effect. Of course, it would be almost impossible to conduct a double blind, placebo controlled study of this duration – especially if one is using urinary excretion as a measure of polyphenol intake.
  • The study did not report the dietary sources of the polyphenols, although this information was presumably available from the dietary recalls. Because the study was conducted in the Chianti region of Italy it is probably pretty safe to assume that red wine contributed to the polyphenol intake. However, people in that region of Italy also tend to consume diets rich in fruits and vegetables. Hopefully, future studies will help determine whether some polyphenols are more important for longevity than others.

The Bottom Line:

1)     Eat lots of fresh fruits and vegetables. They’ll make you healthier, and you just may live longer.

2)     If you like red wine, drink it in moderation. Just don’t assume that it can substitute for a healthy diet. This study measured total polyphenols, not just red wine polyphenols.

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.

Soy And Breast Cancer Recurrence

The Truth About Soy And Breast Cancer

 Author: Dr. Stephen Chaney

SoybeanYou’ve probably heard the warnings: “Soy may increase the risk of breast cancer!” “Women with breast cancer shouldn’t use soy!”

The first warning was never true. Numerous clinical studies have shown that consumption of soy protein is associated with a lower risk of developing breast cancer.

Furthermore, the science behind the second warning has never been very strong. The concerns that soy might stimulate the growth of breast cancer cells was based primarily on cell culture experiments and one experiment in mice – even though a second experiment in mice came to the exact opposite conclusion.

Was The Hypothesis That Soy Could Increase The Risk Of Breast Cancer Recurrence Plausible?

The possibility that soy isoflavones could stimulate the growth of estrogen- responsive breast cancer was biochemically plausible because soy isoflavones bind to the estrogen receptor and have a very weak stimulatory effect (much weaker than estrogen itself).

Even that evidence was not definitive because soy isoflavones also turn on several tumor suppressor pathways in breast cells and help strengthen the immune system – so they could just as easily inhibit the growth of breast cancer cells.

However, because the concerns were plausible and had not been definitively disproved, most experts, including me, recommended for several years that women with estrogen- responsive breast cancer might want to avoid soy protein.

Has The Hypothesis Been Rigorously Tested?

In fact, the definitive clinical studies have been performed, and it turns out for women who are breast cancer survivors, consumption of soy foods does not increase either the risk of breast cancer recurrence or of dying from breast cancer.

The first of these studies was reported in the December 2009 issue of the Journal of the American Medical Association by researchers at Vanderbilt University and Shanghai Institute of Preventive Medicine (Shu et al, JAMA, 302: 2437-2443, 2009).

It was a large, well designed, study that enrolled 5042 Chinese women aged 20 to 75 years old who had been diagnosed with breast cancer and followed them for an average period of 3.9 years.

The women were divided into four groups based on the soy content of their diet (ranging from 5 grams/day to 15 grams/day). The results were clear cut. Breast cancer survivors with the highest soy intake had 25% less chance of breast cancer recurrence and 25% less chance of dying from breast cancer than the women with the lowest soy intake.

The effect was equally strong for women with estrogen receptor-positive and estrogen receptor negative cancers, for early stage and late stage breast cancer and for pre- and post-menopausal women. In short this was a very robust study.

The study also showed that soy protein intake did not interfere with tamoxifen, a drug that blocks the binding of estrogen to its receptor on cancer cells. Tamoxifen is used for both for treating estrogen-responsive breast cancer and preventing its recurrence. In this study, the reduction in the risk of breast cancer recurrence & death was just as great whether the breast cancer survivors were taking tamoxifen or not.

In fact, tamoxifen was protective only for women with low soy intake. It conferred no extra protection for the women at the highest level of soy intake because the soy isoflavones were also blocking the binding of estrogen to its receptor.

Other Clinical Studies

If that were the only published clinical study to test the soy-breast cancer hypothesis, I and other experts would be very cautious about making definitive statements. However, at least four more clinical studies have been published since then, both in Chinese and American populations. The studies have either shown no significant effect of soy on breast cancer recurrence or a protective effect. None of them have shown any detrimental effects of soy consumption by breast cancer survivors.

A meta-analysis of all 5 studies was published earlier this year (Chi et al, Asian Pac J Cancer Prev., 14: 2407-2412, 2013). This study combined the data from 11,206 breast cancer survivors in the US and China. Those with the highest soy consumption had a 23% decrease in recurrence and a 15% decrease in mortality from breast cancer.

The Bottom Line:

What does this mean for you if you are a breast cancer survivor?

1)     There are many reasons to include soy protein foods as part of a healthy diet. Soy foods are one of the highest quality vegetable protein sources and provide a great alternative to many of the high fat, high cholesterol animal proteins in the American diet.

2)     I personally feel that these studies are clear cut enough that breast cancer survivors no longer need to fear soy protein as part of a healthy diet.

3)     The responsible websites agree with this assessment. For example, WebMD and the American Institute for Cancer Research (AICR) both say that breast cancer survivors need no longer worry about eating moderate amounts of soy foods.

4)     The irresponsible websites (I won’t name names, but you know who they are) are still warning breast cancer survivors to avoid soy completely. As a scientist I really have problem with people who are unwilling to change their opinions in the face of overwhelming scientific evidence to the contrary.

5)     Of course, some of those bloggers have now shifted their arguments to say that it is unfermented or genetically modified soy that causes breast cancer. Those statements are equally bogus – but that’s another story for another time.

6)     Finally, I want to emphasize that the published studies merely show that soy does not increase the risk of breast cancer and is safe to use for breast cancer survivors. None of those studies suggest that soy is an effective treatment for breast cancer. The protective effects of soy are modest at best. If you have breast cancer, consult with your physician about the best treatment options for you.

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 Omega-3 Fatty Acids Decrease Risk Of Depression In Women?

Do Happy Fish Make Happy Women?

Author: Dr. Stephen Chaney

Woman playing with autumn leaves The days are getting shorter, and those shorter days can lead to depression. You may have seen the recent headlines saying “Omega-3 fatty acids may decrease the risk of depression in women”. If you suffer from seasonal depression, should you be stocking up on fish oil capsules? Let’s look at the study behind the headlines.

The Theory Behind The Study

Depression appears to be increasing in modern society. For example, between 1991 and 2002, the prevalence of major depression has more than doubled in the United States from 3.3% to 7.1%.

There are many causes of depression, but some experts blame the dramatic increase in omega-6 fatty acids in the diet.  For example, per capita consumption of soybean oil, much of it in processed foods, has increased 1000-fold during the past century. That’s a concern because omega-6 fatty acids interfere with the body’s ability to convert vegetable sources of omega-3 fatty acids into the longer chain omega-3 fatty acids thought to be effective in reducing depression.

This has lead to the hypothesis that omega-3 fatty acids in the diet may help prevent depression, and a number of clinical studies have supported that hypothesis.

How Was The Study Designed?

The study (M. A. Beydoun et al, J. Nutr., doi: 10.3945/jn.113.179119, 2013) looked at 1,746 adults age 30-64 living in Baltimore Maryland. The participants were a representative sample of African Americans and whites, men and women. Omega-3 fatty acid intake was based on two 24-hour dietary recalls. Depressive symptoms were based on something called CES-D, which is a 20 item, self-reporting symptom rating scale.

What Did The Study Actually Show?

The results were pretty dramatic for women:

  • Women with the highest intake of omega-3 fatty acids/day were 49% less likely to suffer from depression than women with the lowest intake.
  • No significant effect of omega-3 fatty acid intake on the prevalence of depression was seen for the men in this study. This was the first study to look at men and women separately, so it’s not yet clear whether this is a true sex-specific difference or simply due to the relatively small sample size and reduced incidence of depression in men.

Limitations Of The Study:

There were numerous limitations to this study, but the most important were:

  • It did not ask whether the participants were taking fish oil supplements, and it did not substantiate the dietary recalls by measuring actual levels of omega-3 fatty acids in the blood.
  • It just measured associations, not cause and effect.

The Bottom Line:

This is not a particularly strong study, but it is consistent with a least half a dozen other studies that have obtained similar results. So, based on the total body of published studies my recommendations are:

1)     If you are a woman and you’re suffering from mild depression you might want to talk with your doctor about increasing your omega-3 fatty acid intake before you start taking an anti-depressive medication. Omega-3 fatty acids may reduce heart disease risk, lower inflammation and provide other benefits. The drugs generally have side effects rather than side benefits.

2)    We don’t have any good data yet on what dose of omega-3 fatty acids are needed, but the 500-1,000 mg/day that the NIH recommends for heart health might be a good starting place.

3)     If you’re a guy, this paper suggests that the jury is out about whether omega-3s can help you with depression. More studies will be required. In the meantime, just remember that omega-3s have lots of other health benefits.

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

Does the Blood Type Diet Really Work?

Is Eating Right For Your Blood Type A Sham?

Author: Dr. Stephen Chaney

cb43e76f-6bf7-4e82-8fc1-95005d2c5626Does the Blood Type Diet really work? In 1997 Dr. Peter J. D’Adamo wrote a book about the blood type diet called “Eat Right 4 Your Type”. Dr. D’Adamo claims that people with different blood types process food differently, so their blood type determines the type of diet that is healthiest for them. Specifically, he claims that people with:

  • Blood group O are descended from hunters and should consume high protein diets.
  • Blood group A are descended from farmers and should consume a near vegetarian diet – completely avoiding red meats.
  • Blood group B are descended from nomads. They have the most flexible digestive system and can eat the widest variety of foods – even dairy products, which he does not recommend for any of the other blood types.
  • Blood group AB are an enigma and are somewhere between blood group A and blood group B.

It’s an interesting concept. Dietary recommendations are made for populations as a whole, and there is tremendous genetic variation in populations. Because of that genetic variation, there is no perfect diet for everyone. Every knowledgeable health expert will tell you that.

The question then becomes “How do you know what kind of diet is healthiest for you?”

The blood type diet is a very simple system. Your blood type is easy to determine. Once you know your blood type you know what to eat. There’s no guesswork.

Could it really be so simple? Over 7 million copies of Dr. D’Adamo’s book have been sold. Millions of people believe in this concept. So it is only fitting to ask “What is the evidence?”

An Objective Scientific Analysis of the Blood Type Diet

There is no doubt that blood type is related to some human genetic and physical traits, but the important question is whether blood type is related to the health outcomes of different diets – the central thesis of Dr. D’Adamo’s book. A Belgian group lead by Dr. Emmey De Buch did a systematic search of the scientific literature to answer that very question (L. Cusack et al, Am J. Clin. Nutr. , 98: 99-104, 2013).

They identified 1415 scientific articles that had the phrase “blood type diet” in either the title or abstract. Then they begin the elimination process. They eliminated:

  • Studies done in test tubes, cell culture, or animals. Only human clinical studies were included.
  • Reviews, commentaries, letters or opinions. Those contained no original scientific research.

At this point they were down to just 16 published clinical studies. Then they asked which of those studies were designed to test the central hypothesis of the blood type diet. They asked:

  • Did the study start with human subjects grouped according to blood type?
  • Did the study have an intervention in which the subjects were required to adhere to a particular type of diet?
  • Did the study measure a health outcome of the dietary intervention?

Guess what? Only one study met these criteria. Just one! And it was a fairly weak study involving a totally different blood typing system than the ABO blood groups.

The Bottom Line:

1)     There is no scientific evidence supporting the blood group diet. A lot has been written about the diet, but nobody has actually shown that it works. The Emperor Has No Clothes!

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 High Protein Diets Your Secret To Successful Weight Loss?

Do High Protein Diets Reduce Fat And Preserve Muscle?

Author: Dr. Stephen Chaney

Healthy Diet food group, proteins, include meat (chicken or turkAre high protein diets your secret to healthy weight loss? There are lots of diets out there – high fat, low fat, Paleolithic, blood type, exotic juices, magic pills and potions. But recently, high protein diets are getting a lot of press. The word is that they preserve muscle mass and preferentially decrease fat mass.

If high protein diets actually did that, it would be huge because:

  • It’s the fat – not the pounds – that causes most of the health problems.
  • Muscle burns more calories than fat, so preserving muscle mass helps keep your metabolic rate high without dangerous herbs or stimulants – and keeping your metabolic rate high helps prevent both the plateau and yo-yo (weight regain) characteristic of so many diets.
  • When you lose fat and retain muscle you are reshaping your body – and that’s why most people are dieting to begin with.

So let’s look more carefully at the recent study that has been generating all the headlines (Pasiakos et al, The FASEB Journal, 27: 3837-3847, 2013).

The Study Design:

This was a randomized control study with 39 young (21), healthy and fit men and women who were only borderline overweight (BMI = 25). These volunteers were put on a 21 day weight loss program in which calories were reduced by 30% and exercise was increased by 10%. They were divided into 3 groups:

  • One group was assigned a diet containing the RDA for protein (about 14% of calories in this study design).
  • The second group’s diet contained 2X the RDA for protein (28% of calories)
  • The third group’s diet contained 3X the RDA for protein (42% of calories)

In the RDA protein group carbohydrate was 56% of calories, and fat was 30% of calories. In the other two groups the carbohydrate and fat content of the diets was decreased proportionally.

Feet_On_ScaleWhat Did The Study Show?

  • Weight loss (7 pounds in 21 days) was the same on all 3 diets.
  • The high protein (28% and 42%) diets caused almost 2X more fat loss (5 pounds versus 2.8 pounds) than the diet supplying the RDA amount of protein.
  • The high protein (28% and 42%) diets caused 2X less muscle loss (2.1 pounds versus 4.2 pounds) than the diet supplying the RDA amount of protein.
  • In case you didn’t notice, there was no difference in overall results between the 28% (2X the RDA) and 42% (3X the RDA) diets.

Pros And Cons Of The Study:

  • The con is fairly obvious. The participants in this study were all young, healthy and were not seriously overweight. If this were the only study of this type one might seriously question whether the results were applicable to middle aged, overweight coach potatoes. However, there have been several other studies with older, more overweight volunteers that have come to the same conclusion – namely that high protein diets preserve muscle mass and enhance fat loss.
  • The value of this study is that it defines for the first time the upper limit for how much protein is required to preserve muscle mass in a weight loss regimen. 28% of calories is sufficient, and there appear to be no benefit from increasing protein further. I would add the caveat that there are studies suggesting that protein requirements for preserving muscle mass may be greater in adults 50 and older.

The Bottom Line:

1)    Forget the high fat diets, low fat diets, pills and potions. High protein diets (~2X the RDA or 28% of calories) do appear to be the safest, most effective way to preserve muscle mass and enhance fat loss in a weight loss regimen.

2)     That’s not a lot of protein, by the way. The average American consumes almost 2X the RDA for protein on a daily basis. However, it is significantly more protein than the average American consumes when they are trying to lose weight. Salads and carrot sticks are great diet foods, but they don’t contain much protein.

3)     Higher protein intake does not appear to offer any additional benefit – at least in young adults.

4)     Not all high protein diets are created equal. What some people call high protein diets are laden with saturated fats or devoid of carbohydrate. The diet in this study, which is what I recommend, had 43% healthy carbohydrates and 30% healthy fats.

5)    These diets were designed to give 7 pounds of weight loss in 21 days – which is what the experts recommend. There are diets out there promising faster weight loss but they severely restrict calories and/or rely heavily on stimulants, they do not preserve muscle mass, and they often are not safe. In addition they are usually temporary.  I do not recommend them.

6)    This level of protein intake is safe for almost everyone. The major exception would be people with kidney disease, who should always check with their doctor before increasing protein intake. The only other caveat is that protein metabolism creates a lot of nitrogenous waste, so you should drink plenty of water to flush that waste out of your system. But, water is always a good idea.

7)     The high protein diets minimized, but did not completely prevent, muscle loss. Other studies suggest that adding the amino acid leucine to a high protein diet can give 100% retention of muscle mass in a weight loss regimen – but that’s another story for another day.

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

Health Tips From The Professor