(06-11-12) Harvard explains why people regain weight with the Atkins diet

Posted on October 9, 2012 by Dr. Barry Sears

A study from Harvard Medical School explains that even though people can lose
weight on a ketogenic diet, all lost weight usually rapidly returns.

Ketogenic diets have been recommended for decades for rapid weight loss. The
most famous is the Atkins diet. Ketogenic diets are based on high-protein and
very low-carbohydrate intake. For the past 40 years such diets have been
routinely used in America for weight loss, yet America remains in the midst of
a growing epidemic of obesity. While ketogenic diets can induce initial weight
loss, all lost weight usually rapidly returns, resulting in more weight (and
even more fat) than when the person started the ketogenic diet.

For many years it was thought that such weight regain was due to poor dietary
compliance. Now Harvard Medical School in an article in the June 27, 2012,
issue of the Journal of the American Medical Association shows the reason for
weight regain is more ominous than simple dietary non-compliance. In carefully
controlled studies Harvard researchers demonstrated that on a ketogenic diet
the levels of the hormone cortisol increase by 18%, and the levels of active
thyroid hormone (T3) control metabolism decrease by 12% (1).

The effect of increased cortisol is to cause rapid fat accumulation, as any
patient who has ever used prescription cortisol-like drugs knows. It also
causes depression of the immune system, loss of memory, and thinning of the
skin. These are also hallmarks of the acceleration of the aging process.
Furthermore, the lowering of the active form of the thyroid hormone slows down
the metabolism, making even seemingly small increases in calorie intake result
in increased body fat accumulation. Besides setting you up to regain all the
lost weight, the Atkins diet apparently also increases the rate of aging.

However, many people seem willing to continue to try such ketogenic diets in
hopes of losing weight quickly. Yet highly controlled studies I published in
the world?s most prestigious nutrition journal in world more than six years ago
demonstrated that is simply not a true statement (2). In this study either a
ketogenic diet (the Atkins diet) or a non-ketogenic diet (the Zone Diet) were
compared in obese individuals. For the first six weeks all meals for both
groups were prepared in a metabolic kitchen at Arizona State University (in
essence treating subjects like lab rats). Both diets contained an equal number
of calories.

When it came to weight loss, the subjects following the Zone Diet actually
lost slightly more weight than as those on the ketogenic diet during the
initial six-week period as shown in Figure 1.


Source: Drsears.com

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