Healthy Living Archives - Page 2 of 2 - Health Tips From The Professor

Do Avocados Lower Cholesterol?

January 20, 2015 by Dr. Steve Chaney

Should Avocados Be On The Super Fruits List?

Author: Dr. Stephen Chaney

You may have seen the recent headlines suggesting that avocados lower cholesterol, are a miracle fruit, and reduce your risk of heart disease. Some of those articles are suggesting that you try to eat an avocado every day. Are those headlines true? Should you be eating more avocados?

If you are like me that would be a bit of a stretch. I prefer my fruits tastier and a bit less greasy, but I won’t let my personal preferences color my analysis of the data. Let’s start by looking at the rationale for testing the effect of avocados on cholesterol levels.

The 2013 American Heart Association Guidelines on Lifestyle Management to Reduce Cardiovascular Risk recommends reducing saturated fats to no more than 5% to 6% of total calories (In the typical American diet about 13% of calories come from saturated fat). The AHA recommends replacing the saturated fat with either monounsaturated fat or polyunsaturated fat (vegetable oils and fish oil).

In addition, a major clinical study has recently shown that a Mediterranean diet supplemented with either olive oil or mixed nuts (walnuts, hazelnuts and almonds) lowers cholesterol and reduces the incidence of major cardiovascular events by ~30% over 5 years in men and women aged 50 to 80 who were at high risk for cardiovascular disease (Estruch et al, N Engl J Med, 368: 1279-1290, 2013).

One avocado has about the same amount of oleic acid (a monounsaturated fat) as 2 tablespoons of olive oil or 1.5 ounces of almonds, so it is logical to suspect that avocados might have a similar effect as olive oil or nuts.

How Was The Clinical Study Designed?

Because there is still a lot of controversy as to whether diets in which the saturated fat is replaced with healthier fat or no fat at all (low fat diets) are better, this study (Wang et al, J Am Heart Assoc, 2015;4: e001355 doi:10.1161/JAHA.114.001355) compared 3 diets:

A low fat diet in which most of the saturated fat was replaced with carbohydrate (24% total fat, 7% saturated fat, 11% monounsaturated fat, 6% polyunsaturated fat, 59% carbohydrate, 16-17% protein).

A moderate fat diet in which most of the saturated fat was replaced with pure oleic acid (34% total fat, 6% saturated fat, 17% monounsaturated fat from oleic acid, 9% polyunsaturated fat , 49% carbohydrate, 16-17% protein).

A moderate fat diet in which most of the saturated fat was replaced with avocado (34% total fat, 6% saturated fat, 17% monounsaturated fat from avocado, 9% polyunsaturated fat , 49% carbohydrate, 16-17% protein).

The study subjects were 45 healthy overweight or obese men and women (age 21 to 70, average = 45). Each subject was put on all 3 diets sequentially for 5 weeks each in a random order. That way each subject served as his or her own control.

The diets were carefully controlled to keep the calories the same so that none of the subjects lost weight during the study (weight loss would have confounded the results because weight loss lowers cholesterol in most individuals). The subjects were also told not to change their exercise habits. In short, it was a small study, but it was very well designed.

When the low fat diet was compared to the moderate (healthy) fat diets, the results were pretty similar to a number of other studies:

Total cholesterol and LDL cholesterol (the bad type) were lowered to about the same extent by both types of diets.

Triglycerides were higher and HDL cholesterol (the good type) was lower for the low fat diet compared to the moderate (healthy) fat diets.

Because this has been shown in previous studies, I won’t discuss it further here.

Do Avocados Lower Cholesterol?

When the authors compared the diet in which saturated fat was replaced with avocados to the diet in which saturated fat was replaced with oleic acid there were a number of significant differences.

Both LDL-cholesterol and non-HDL cholesterol were significantly lower on the avocado diet than the oleic acid diet. The decrease was about 10%. Based on the metrics adopted by the American Heart Association this has the potential to translate into a 20% decrease in heart disease risk.

The avocado diet was the only one of the three diets that significantly decreased LDL particle number, small dense LDL cholesterol and LDL/HDL ratio, Many experts think that these parameters are better indicators of hearts disease risk than LDL cholesterol levels.

Do avocados lower cholesterol? The short answer is yes, eating an avocado a day can lower cholesterol levels and might possibly lower heart disease risk. But to understand the true implications of this study we need to dig a little deeper.

What Is the Significance of This Study?

This study has one important take home lesson and raises two important questions.

Take Home Lesson: Foods Are More Important Than Fats We often hear about the benefits of including more monounsaturated fats in our diet, but when you actually make a direct comparison, such as was done in this study, it turns out that it is the foods that contain monounsaturated fats that make the difference, not the monounsaturated fats themselves. The oleic acid diet was only marginally better than the low fat diet at lowering total and LDL cholesterol.

This was the major conclusion of the authors of the study. Everything else was made up by the non-experts who write the articles that you see in the papers and on the internet. It is yet one more example of the headlines getting ahead of the science.

The authors admitted that we have no idea why avocados are more effective at lowering cholesterol than an equivalent amount of oleic acid. They speculated that it could be due to the high content of phytosterols in avocados. However, while the 114 mg of plant sterols in an avocado makes it an excellent source of plant sterols, it is far below the 2,000 mg of plant sterols that the NIH considers optimal for lowering cholesterol levels.

The authors also mentioned soluble fiber and specialized sugars in an avocado, but none of those was present in sufficient quantities to explain the cholesterol-lowering effect of avocados by itself. It is likely that all of those constituents plus others that we have not yet identified are what make avocados more effective than oleic acid at lowering cholesterol.

Question 1: Do We Really Want To Eat An Avocado a Day?

We need to keep in mind that a single avocado weighs in at around 234 calories. That is:

2.5 times the calories in an apple
4.7 times the calories in a peach or a cup of strawberries
5.7 times the calories in a half cup of blueberries
7.3 times the calories in a half cup of raspberries or blackberries

You get the point. What made this study so effective is that all three diets were designed to provide exactly the same number of calories so that nobody gained or lost weight. If you are thinking of adding an avocado a day to your diet, you are going to need to significantly cut back on calories somewhere else, or your weight gain will drive your cholesterol levels in the wrong direction.

Question 2: What Are The Long Term Implications of This Study?

The bottom line is that this and previous studies suggest that avocados should rightfully be included along with olive oil and nuts as healthy sources of monounsaturated fats that can help you lower cholesterol levels and may reduce your risk of heart disease.

However, we need to keep in mind that while a major clinical study has shown that adding either olive oil or nuts to your diet can reduce heart disease risk, we don’t have a comparable study showing that adding avocados to your diet will have the same benefit. It is plausible, but has not yet been demonstrated.

The Bottom Line

A recent clinical study has shown that eating an avocado a day was more effective at lowering bad cholesterol than adding an equivalent amount of the monounsaturated fat oleic acid to the diet. This suggests that it is the foods that contain the monounsaturated fats that make the difference, not the monounsaturated fats themselves.

This and previous studies suggest that avocados should rightfully be included along with olive oil and nuts as healthy sources of monounsaturated fats that can help you lower cholesterol levels and may reduce your risk of heart disease.

However, we need to keep in mind that while a major clinical study has shown that adding either olive oil or nuts to your diet can reduce heart disease risk, we don’t have a comparable study showing that adding avocados to your diet will have the same benefit. It is plausible, but has not yet been demonstrated.

You also need to keep in mind that a single avocado contains 234 calories. What made this study work so well is that each diet was carefully designed to provide exactly the same number of calories. If you are thinking of adding an avocado a day to your diet, you are going to need to significantly cut back on calories somewhere else, or your weight gain will drive your cholesterol levels in the wrong direction.

Finally, the American Heart Association Guidelines are to reduce saturated fats to no more than 6-7% of total calories. So while the low-carbohydrate, butter, bacon, and steak diet may give you temporary weight loss, it is definitely NOT recommended if you want to reduce your risk of heart disease. For more on this important topic, see my previous health tip “Are Saturated Fats Good 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.

Vitamin D Deficiency

January 13, 2015 by Dr. Steve Chaney

What Is The Real Vitamin D Story?

Author: Dr. Stephen Chaney

If you are like most people, you probably don’t know what to believe about vitamin D deficiency. Some experts tout vitamin D as a miracle nutrient that will help you lead a longer, healthier life. They leave you with the impression that everyone should be supplementing with vitamin D.

Other experts tell you that the supposed benefits of vitamin D are all hype. They tell you not to waste your money on vitamin D supplements.

When you pull back the curtain and look at the clinical studies behind the headlines, a pattern begins to emerge.

Most of the studies that support a role for vitamin D in preventing heart disease, preventing cancer and extending life have been population studies. They have compared populations with low vitamin D intake with populations with adequate vitamin D intake. While population studies are good for suggesting associations, they have their limitations:

Population studies are good at suggesting associations, but they do not prove cause and effect.

With population studies it is also very difficult to eliminate what scientists call “confounding variables”. Let me give you an example. Suppose someone had low 25-hydroxyvitamin D levels in their blood because they sat around all day watching TV and never got out in the sun. If they got sick you wouldn’t really know whether it was due to low 25-hydroxyvitamin D levels or due to inactivity. In this case, inactivity would be a confounding variable.

On the other hand, most of the studies that fail to find any benefit of vitamin D are double blind, placebo-controlled intervention studies in which one group was given supplemental vitamin D and the other group was given a placebo. While these studies are considered the most reliable clinical studies, they have their limitations as well.

In the case of vitamin D many of these studies were done with a cross section of the population in which most of the participants already had adequate blood levels of 25-hydroxyvitamin D at the start of the study. Those studies are incapable of telling us whether correcting a vitamin D deficiency would have been beneficial.

Even when the intervention studies focus on participants with low vitamin D status at the start of the trial they have another significant limitation. They are all short term studies. Typically, the best of these studies last no more than a couple of years. Longer term studies are far too expensive. In contrast, diseases such as heart disease and cancer take decades to develop. A one or two year intervention with vitamin D simply may not be sufficient to correct the damage caused by decades of vitamin D deficiency

This is the current dilemma that is creating all of the confusion in the vitamin D story. For the most part, population studies and intervention studies are coming to very different conclusions. And both kinds of studies have inherent limitations that are difficult to overcome.

Fortunately, a new kind of clinical study has been developed in recent years that overcomes the limitations of both population studies and intervention studies.

A New Kind of Clinical Study

The new approach is something called mendelian randomization. I apologize for the scientific jargon, but let me explain. In this case you are separating your population based on genetic variation rather than on the basis of biochemical or behavioral differences.

For example, in the clinical study I will describe in a minute the population was separated into groups based on genetic variations in the DHCR7 and CYP2R1 genes. The first gene is involved in the biosynthesis of cholesterol, which is a precursor of vitamin D, and the second gene converts vitamin D to 25-hydroxyvitamin D. Both genes affect blood levels of 25-hydroxyvitamin D.

This kind of study has several unique strengths:

Genetic variations are unaffected by confounding variables such as sun exposure, obesity, smoking, inactivity, and poor diet. If the study population is large enough, those confounding variables will be equally distributed among groups that are selected solely on the basis of genetic variations.

These studies are long term by definition. If someone has a genetic variant that lowers their 25-hydroxyvitamin D level, it will do so for their entire lifetime. They can increase their vitamin D status by sun exposure, for example, but their blood levels of 25 hydroxyvitamin D will always be less than someone with equal sun exposure who does not have that genetic variant.

Because these studies reflect lifelong exposure to 25-hydroxyvitamin D they are ideally suited for measuring the effect of vitamin D status on mortality and diseases that take decades to develop.

Do Vitamin D Genes Affect Mortality?

This study (S. Afzal et al, The British Medical Journal, 2014;p 349:g6330 doi: 10.1136/bmj.g6330) combined the data from three clinical studies conducted in Copenhagen between 1976 and 2013. The age of the participants ranged from 20 to 100 years and the follow-up was 6-19 years. 95,766 participants in these studies were genotyped for variants in the DHCR7 and CYP2R1 genes which were known to affect 25-hydroxyvitamin D levels. 35,334 of those participants also had blood 25-hydroxyvitamin D levels determined. By the end of the study 10,349 of the participants had died.

The individual genetic variants included in this study caused a relatively small (1.9 nmol/L) decrease in blood levels of 25-hydroxyvitamin D. However, because this was a very large study and the participants with those genetic variants were exposed to lower 25-hydroxyvitamin D levels for their entire lifespan, the decreased 25-vitamin D levels were associated with significant increases in all cause mortality and cancer mortality, but not with increased cardiovascular mortality.

When they extrapolated to a genetically caused 20 nmol/L decrease in 25-hydroxyvitamin D, the decrease in 25-hdroxyvitamin D was associated with a 30% increase in all cause mortality and a 30% increase in cancer mortality.

What Kind Of Studies Are Needed Next?

The authors noted that this is the first study of its kind, so it obviously needs to be confirmed by other large mendelian randomization studies that test the link between vitamin D status and mortality.

Ideally, it should also be verified by double blind, placebo controlled intervention studies, but that may not be possible. If one really wanted to verify this study, the intervention study should start with a population group with 25-hydroxyvitamin D levels at least 20 nmol/L below what is considered adequate and provide them with enough supplemental vitamin D to increase their 25-hydroxyvitamin D to the adequate range. That is difficult, but doable.

However, the intervention study would also need to be long enough (decades perhaps) to prevent cancer from developing. That kind of study will probably never be done.

The Bottom Line

The relationship between vitamin D status and mortality has been investigated with a new type of clinical study based on what is called mendelian randomization. Population groups were segregated based on genetic variations in two genes that affect blood 25-hydroxyvitamin D levels (a measure of vitamin D status).

This study concluded that a genetically determined decrease of 20 nmol/L in blood 25-hydroxyvitamin D was associated with a 30% increase in all cause mortality and a 30% increase in cancer mortality, but had no significant effect on cardiovascular mortality.

This kind of study is particularly strong because it measures the affect of lifelong exposure to 25-hydroxyvitamin D. This is important when assessing the effect of vitamin D status on mortality and diseases such as cancer that take decades to develop. In contrast, the double blind, placebo controlled intervention studies that are consider the “Gold Standard” for clinical studies may be too short term to adequately assess the effect of vitamin D status on cancer or all cause mortality.

This study supports the benefit of maintaining optimal vitamin D status, but it is the first clinical study of its kind and needs to be confirmed by other studies.

In the meantime, there is no harm to in maintaining your blood levels of 25-hydroxyvitamin D in the optimal range through diet, sun exposure and supplementation. This study suggests it just may help you live a longer, healthier life.

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 Green Coffee Bean Extract Work?

October 14, 2014 by Dr. Steve Chaney

Author: Dr. Stephen Chaney

Does the green coffee bean extract work? The claims sounded so appealing. You could just take this green coffee bean extract and the pounds would melt away. You didn’t need to exercise or change your diet.

Your first reaction when you heard those claims was probably “Right, when pigs fly. I’ve heard this kind of stuff before. It’s just too good to be true.”

But then you were given a pseudo-scientific explanation about how it was the chlorogenic acid in the green coffee bean extract that was responsible for its amazing properties (What they didn’t tell you was that chlorogenic acid is present in all roasted coffees). You were told that it was backed by a clinical study showing that people lost 17.7 pounds, 10.5% of their body weight and 16% of their body fat in 22 weeks without diet and exercise.

To top it all off you were told that it was endorsed by Dr. Oz on his TV show and provided with a video clip to prove it. After all of that you were probably tempted to say “Maybe…just maybe… these amazing claims might be true.” You may have even been tempted to try it.

Were the claims true? Is green coffee bean extract the miracle weight loss product that everyone has been looking for? Or was it just another bogus weight loss product?

Is Green Coffee Bean Extract Bogus?

Evidently the Federal Trade Commission did not consider the claims about green coffee bean extract to be true. The FTC sued one of the companies that manufactured and sold green coffee bean extract for promoting a “hopelessly flawed study” to support the weight loss claims for their product.

The FTC alleged that:

The study was too small, at 16 subjects, to provide convincing data.

The study contained a number of critical flaws in the design and results of the study. For example, the greatest weight loss actually occurred in the placebo group.

The lead investigator in India actually falsified the results.

The company knew or should have known that this botched study didn’t prove anything.”

The manufacturer eventually agreed to pay $3.5 million to the FTC to settle their complaint. Basically, the company agreed with the FTC that there was no evidence to back their weight loss claims.

How Did Dr. Oz Get It So Wrong?

What about Dr. Oz’s endorsement? In Dr. Oz’s 2012 show segment he called green coffee bean extract “the magic weight loss cure for any body type.” The most puzzling aspect of this whole saga is how Dr. Oz got it so wrong.

After all, he is a trained neurosurgeon. He is Vice Chair of the Department of Surgery at Columbia University. He understands the principles of evidence-based medicine. Evidence-based medicine simply means that it is a physician’s responsibility to check the scientific evidence before recommending a treatment to a patient. Yet he never even looked into the supposed “clinical study” backing green coffee bean extract’s weight loss claims.

In a Senate hearing this past June Dr. Oz apologized. He said: “For my colleagues at the FTC, I realize I have made their jobs more difficult.”

How Can You Protect Yourself Against Weight Loss Scams?

There are dozens, if not hundreds, of new weight loss products appearing on the market every year. The FTC is doing its best to police the claims that are being made, but they are clearly overwhelmed. And even when they have an airtight case, it can take years for them to force a company to stop making false claims.

So, how can you protect yourself against weight loss scams? How can you avoid wasting your money on products that don’t work, or may even harm your health? I advise a little healthy skepticism.

Be skeptical about the claims. The old adage “If it sounds too good to be true, it probably is [too good to be true]” is always good advice. In a previous “Health Tips From the Professor” I discussed the the FTC’s recommendation for “7 Easy Ways To Spot Fad Diets”. That one is probably worth printing out and keeping handy so that you can review it the next time a new diet program comes out.

Be skeptical about the studies. The bottom line is that not all clinical studies are reliable. I realize that it is extremely difficult for a non-scientist to evaluate the validity of clinical studies. My best advice is to go online and see what other experts are saying about the study and the claims. There are a number of “fact checker” blogs online that focus on careful scientific analysis of product claims and the “studies” that support them.

Be skeptical about the endorsements. Unfortunately, there are far too many examples of well known doctors who have endorsed bogus product claims on their TV shows or in their blogs. That makes it even more difficult for the layman to separate fact from fiction. My advice is to simply ask the question: “Does their blog or TV show feature something novel, something spectacular, and/or something sensational…every single week?”

My belief is that these experts all start out with good intentions. However, to develop a really big audience and keep them engaged they feel pressured to deliver novel and sensational health news every single week. The reality is that there are not advances every single week that are novel, sensational… and scientifically accurate. Eventually, they feel pressured to sacrifice accuracy for novelty.

That is why my blog is different. I don’t promise you spectacular and sensational news every week, but I do promise you accuracy. I will share the latest headlines, but I will tell you both their strengths and their weaknesses. Ultimately, it is your responsibility to protect yourself against weight loss scams and I tell you how below. Fortunately, what you can always count on from me is I will be honest with you.

So, does the green coffee been extract work?

The Bottom Line

According to the FTC the green coffee bean extracts that were so widely promoted a couple of years ago were yet another example of bogus weight loss products. The FTC sued one of the companies that markets and sells green coffee bean extract for promoting a “hopelessly flawed” clinical study to advertise their product, and the company has recently settled with the FTC for $3.4 million.
The only way that you can protect yourself from bogus weight loss products is to be skeptical. I discuss the questions you should ask in more detail above, but in short:
- Be skeptical of claims that sound too good to be true.

Be skeptical of the clinical studies the companies quote to support their claims.

Be skeptical of expert endorsements. This product was even endorsed by Dr. Oz on his TV show.

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.

Best Diet For Weight Loss

September 23, 2014 by Dr. Steve Chaney

The Diet Wars Heat Up Again

Author: Dr. Stephen Chaney

What is the best diet for weight loss? One week the headlines say that low-carbohydrate diets are better. The next week it’s low-fat diets that are better. There is even the occasional headline proclaiming that it doesn’t matter which diet you follow as long as you control your calories. It is no wonder that you are confused.

It is unusual, however, to have conflicting headlines within the same week, but that is exactly what happened last week. Let me take you behind the headlines to the actual clinical studies and help you sort through the conflicting headlines.

Are Low-Carbohydrate Diets Best For Weight Loss?

The manuscript behind this headline was published September 2nd in the Annals of Internal Medicine (Bazzano et al, Annals of Internal Medicine, 161: 309-318, 2014). This study was designed to determine which was the best diet for weight loss, low carb diet or low fat diet. The study recruited 148 overweight participants (mean age, 46.8, 88% female, 51% black) and randomly assigned them to either a low-fat diet or low-carbohydrate diet.

The participants on the low-fat diet were instructed to consume <30% of their calories from fat, while the participants on the low-carbohydrate diet were told to limit carbohydrates to <40 g/day. Neither group was told to limit calories. They met with a dietitian 10 times during the 12-month study and received information on dietary fiber (target = 25 g/day) and healthy fats (target = <7% saturated fat and little or no trans fats).

At the end of 12 months the low-carbohydrate diet resulted in significantly greater…

Weight loss (7.7 pounds)…

Decrease in triglyceride levels…

Increase in HDL cholesterol…

Decrease in the ratio of total to HDL Cholesterol…

…than the low-fat diet. In short, the results suggested that the low-carbohydrate diet was not only better than the low-fat diet for weight loss, but that it was also more effective in reducing risk factors for cardiovascular disease.

Case closed, you might be tempted to say. The low carb diet is the best the diet for weight loss. But there have been lots of other studies that have come to the opposite conclusion. So we have to ask the question: “Is this study significantly better than all of the studies that have failed to find any difference between the low-fat and low-carbohydrate diets with respect to weight loss and cardiovascular risk?”

What Are The Strengths & Weaknesses Of the Study?

Strengths of the Study: This was a very well designed study. In particular:

Dietitians met with the participants at multiple times during the program to assure adherence to the diet, which was very good.

The study utilized multiple dietary recalls, both during the week and on weekends.

The study had a diverse population.

Weaknesses of the Study:

The study did not control calories. In fact, the caloric intake was ~160 calories/day greater for the low-fat group than the low-carbohydrate group for at least the first 6 months of the study. That alone would be enough to account for the 7.7 pounds difference in weight loss.The reason for the higher caloric intake of low-fat group is not known. It could be due to the lower palatability of the low-carbohydrate diet. Alternatively, it could be due to the lower satiety of the low-fat diet. It was low in both fat and protein, both of which contribute to satiety (the feeling of fullness after we eat).
The study did not specify the type of carbohydrates consumed. The dietitians instructed the participants on the type of fat they should be eating, but not the type of carbohydrate. That was a significant omission. Diets high in sugars and refined carbohydrates provide less satiety and adversely affect cardiovascular risk factors compared to diets where the carbohydrate comes primarily from fresh fruits, vegetables and legumes.
The study did not control protein intake. In fact, the low-fat group consumed significantly less protein than the low-carbohydrate group. As I pointed out in a previous “Health Tips From the Professor” High Protein Diets and Weight Loss , higher protein intakes are essential for maintaining muscle mass during weight loss. That is important because loss of muscle mass can decrease metabolic rate (the rate at which we burn calories 24 hours a day – even at rest).

The amount of protein consumed by the low-carbohydrate group was close to the amount shown to maintain muscle mass during weight loss, while the amount of protein consumed by the low-fat group was close to the amount associated with loss of muscle mass during weight loss. That was reflected in the results. The low-fat group lost muscle mass while the low carbohydrate group actually gained muscle mass. The resulting difference in muscle probably meant that the low-carbohydrate group was burning more calories on a daily basis than the low-fat group.

In short, this is a good study, but it has important flaws. It is not a game changer.

Do Low-Carbohydrate & Low-Fat Diets Result In Identical Weight Loss?

The study behind this headline was published in the September 3rd edition of the Journal of the American Medical Association (Johnson et al, JAMA, 312: 923-933, 2014). This study was a meta-analysis that combined the results of 48 studies with 7286 participants. When the authors combined the data from all of the published studies there was no difference in weight loss for the low-fat and low-carbohydrate diets over a one or two year period.

The strength of the study is that it combines the results of multiple studies. That increases the statistical power of the observations and smoothes over the effect of outlier studies, such as the one described above. This is the study I would trust.

What Do The Experts Say?

Dr. Walter Willett, Chair of the Department of Nutrition at the Harvard School of Public Health was quoted as saying: “…some people [would] do well on either diet. The key issue for each person is finding a way of eating that is healthy and can be maintained for the long term.”

Dr. Bradley Johnson (the author of the meta-analysis) was quoted as saying: “The take home message is that people should choose a diet they can adhere to…”

The Bottom Line

1) Ignore the recent headlines suggesting that low-carbohydrate diets may be more effective than low-fat diets for weight loss. When you control for calories and protein intake there is no difference between the two diets with respect to long term weight loss.

2) You can also ignore the headlines telling you that low-carbohydrate diets are better for cardiovascular health. You don’t need to avoid carbohydrates to have a healthy heart. You just need to make healthy carbohydrate choices – fruits, vegetables, legumes and whole grains instead of refined flour products and sugary junk food.

3) Experts will tell you that the best diet is a healthy diet that you can stick with long term.

4) My personal recommendations are to avoid extremes (either low-fat or low-carbohydrate). Instead:

Aim for moderate amounts of healthy fats and healthy carbohydrates.

Don’t ignore protein. Make sure you get enough protein to maintain your muscle mass.

Control calories by reducing portion sizes and choosing healthy snacks.

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 Organic Foods Healthier?

August 12, 2014 by Dr. Steve Chaney

Organic Fruits & Vegetables

Author: Dr. Stephen Chaney

Are organic foods healthier for us than conventionally grown foods, specifically fruits and vegetables? The controversy about the benefits of organically raised produce continues. In fact, about the only thing that all sides agree on is that:

Organic foods have lower pesticide and herbicide residues and cause less environmental pollution.
Organic foods generally cost more.

But that is where all agreement ends.

Some experts argue that the pesticide levels on conventionally grown fruits and vegetables are within safe levels and that any risk from the pesticides is outweighed by the health benefits of the fruits and vegetables themselves.
Some studies have suggested that organic foods, fruits and vegetables, are healthier because they have higher antioxidant levels, while other studies have reported no nutritional differences between organic and conventionally grown fruits and vegetables.

Benefits of Organic Food?

The present study (Baranski et al, British Journal of Nutrition, doi: 10.1017/S0007114514001366) tried to overcome the shortcomings of many of the previously published reports.

To begin with this study was a meta-analysis that combined the results from 343 of the best designed previous studies to increase the statistical power of the analysis. In addition, the investigators utilized a type of statistical analysis that was superior to previously published studies. In short, it was a very good study. It does show some benefits of organic food.

The results were fairly clear cut:

Pesticide residues were four-fold lower in the organically raised produce than the conventionally raised produce. This result has been consistently seen in all of the previously published studies, and is probably the #1 reason that people choose organic produce. It is also one of the most agreed upon benefits of organic food.

Polyphenol antioxidant levels were significantly higher in the organically raised produce. The percent increase ranged from 19% to 69% depending on the polyphenolic compound tested. This increase has not been seen in all previously published studies, but would represent a side benefit if true.

Levels of the toxic metal cadmium were significantly less in the organically grown fruits and vegetables. The authors speculated that the cadmium found in conventionally grown produce came from the inorganic fertilizers that were used.

Should You Choose Organic Supplements?

If organic foods are better for you than conventionally grown foods, does that mean that you should also choose organic supplements? While that idea sounds logical, the reality is actually more complex.

While organic foods clearly have less pesticides and toxic metals than conventionally grown foods, the level of those contaminants is not zero – even in foods with organic certification. The problem is that our environment is so polluted that no farm is contaminant free. A farmer can use the best organic practices, but if their groundwater is contaminated or pesticides from neighboring farms blow on to their farm, some of those toxic residues will end up in their “organic” crops.

So with supplements, “Organic” certification is not an absolute guarantee of purity. Instead you should insist on getting your supplements from a company with a very rigorous quality control program and a policy of rejecting any raw materials that contain contaminants of any kind.

The Bottom Line

1) The latest study shows that pesticide residues are four-fold lower in the organically raised produce than the conventionally raised produce. This result has been consistently seen in all of the previously published studies, and is probably the #1 reason that people choose organic fruits and vegetables.

2) Polyphenol antioxidant levels were significantly higher in the organically raised produce. The percent increase ranged from 19% to 69% depending on the polyphenolic compound tested. This increase has not been seen in all previously published studies, but would represent a side benefit if true.

3) While one of the benefits of organic foods is they are less likely to be contaminated than conventionally grown foods, an organic certification is not a sufficient proof of purity when you are choosing supplements.You should insist on getting your supplements from a company with a very rigorous quality control program and a policy of rejecting any raw materials that contain contaminants of any kind.

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.