But the 12-month study by Stanford University, published today in the Journal of the American Medical Association, is the strongest evidence so far that carbohydrates, not fat, are the main culprit in America's struggle to slim down and to lower risk of heart disease.
And that's the big takeaway from this study—that eating the fat of an Atkins diet doesn't increase heart-disease risk, it reduces it.
Dr. Dean Ornish and Zone creator Barry Sears both criticized the study, noting that the subjects slipped from their diets. And even its lead author, Christopher Gardner, Ph.D., noted the weight lost wasn't terribly impressive (average of 10 pounds), and that long-term effects weren't studied. But he said the study showed the Atkins diet may be more healthful than many of its critics have said. After a year their cholesterol and blood pressure readings were slightly better than those on the other three diets.
As Men's Health and The Abs Diet readers know, keeping your carbohydrate intake low (a diet of mostly meat, eggs, cheese and vegetables) keeps your blood sugar from spiking and triggering your body to store fat. And eating plenty of protein will keep you fuller longer.
MensHealth.com talked to low-carb diet researcher Jeff Volek, Ph.D., R.D., of the University of Connecticut, about the study, which he said confirms what many in the weight-loss field already knew. In a nutshell, if you want to drop weight, eat protein, avoid starchy food like bread, pasta, and potatoes, and don't sweat the fat.
Dr. Volek, how should the Men's Health guy react to this news?
This study confirms what has been shown many times in prior studies. It further emphasizes the reliability of low carbohydrate diets to promote weight loss and improve metabolic health. On average, most people do better when they reduce carbohydrates compared to lowering fat.
The take-home message should be that reducing carbohydrates should be a serious consideration for any guy who is not satisfied with his current diet.
If I'm trying to lose weight, can I have a second helping of steak if I skip the baked potato?
Ditch the potato and have another serving of vegetables or steak, but only if you're still hungry. Many will not be. Any meat is okay. Cheese is a good choice.
It's hard for some guys not to think saturated fats are going to make him fat and unhealthy.
We have been trained to believe that fat-and especially saturated fat-is harmful. This has been driven into our consciousness as incontrovertible fact. The fact is that saturated fat has several positive attributes and is only harmful when carbohydrates are also present.
You really have to absorb this last sentence because it explains a lot of the ambiguity and paradoxes that surround dietary saturated fat, including the findings in this JAMA study. The new paradigm points to the level of dietary carbohydrate as having a dominant effect on the fate of saturated fat. If carbohydrate is low, then consuming more saturated fat does not have a harmful effect. In fact, there are many improvements in metabolic risk factors as was the case in the JAMA paper.
The diet with the highest saturated fat had the best response, but this diet also had the lowest amount of carbohydrate. So was the finding surprising? Probably to most people, but there is a perfectly good biological explanation that is consistent with everything we know about biochemistry and metabolism.
This was a study of women. Will the same hold true for men?
The findings are very applicable to men. We have compared low fat and low carbohydrate diets in both men and women in several studies and have found that gender is not a factor when it comes to physiologic responses to low carbohydrate diets.
If anything, men actually respond slightly better to low carbohydrate diets in absolute terms. For example, men on average lose more weight and have greater reductions in triglycerides.
Is this study a big deal?
This study is significant because it provides another strong example of the value of low carbohydrate diets.
Professional organizations promoting low-fat diets have failed to prevent—and are currently unable to curtail—the epidemic of diabetes. Rather than explore all possibilities that might help, they are specifically trying to reduce the options for people-even though the scientific studies continue to show that reducing carbohydrates is at least as effective, and usually considerably better than reducing dietary fat.
Rather than trying to find anything positive that could be used from the numerous publications on low carbohydrate, they ignore almost all of them and have a blanket condemnation.
Any surprises in the study?
The most surprising finding is that some people actually think this is a surprising finding. Anyone remotely in tune with basic biochemistry and metabolism, or who attempts to keep up with the scientific literature in this area, should see this as completely consistent with this idea: Reducing carbohydrates has more favorable effects on weight loss and risk markers for diabetes and heart disease than reducing fat.
There were only 77 women in the study. Is that enough to be conclusive?
We have plotted individual responses in our studies-you don't need a lot of people to see the dramatic differences, especially under controlled conditions. The number in this study helps, compared to other sloppy studies with lower numbers who may miss a statistically significant effect. When good experiments are done, the findings are very consistent and robust.
How the Atkins Diet Benefited the Study Subjects
The women who followed the Atkins diet did not merely lose weight. They improved their health, too. Some facts:
The Ornish dieters ate significantly more fiber (19 grams vs. 15 grams) than the Atkins dieters.
There was no difference in daily calories eaten or burned between any of the diet groups.
Atkins dieters ate significantly more saturated fat daily than those on the other diets. In fact, those following Atkins ate 38 percent more saturated fat a day than those on the Ornish Diet.