NEJM Studies Support Atkins Diet Claims

PHILADELPHIA--Two studies out of Philadelphia, among the first to examine the health effects of a low-carb/high-protein diet for longer than 90 days, found patients on the diet lost more weight and kept it off compared to individuals on a more traditional low-fat weight-loss plan. Published in the May 22 issue of the New England Journal of Medicine (NEJM) (http://content.nejm.org), the studies provide a measure of credibility for the diet popularized by the late Robert C. Atkins, M.D., and dismissed as unhealthy by many mainstream nutrition organizations.

In the first study (348:2074-81), researchers led by Frederick F. Samaha, M.D., from the Philadelphia Veterans Affairs Medical Center, assigned 132 severely obese subjects to a carbohydrate-restricted diet or a calorie- and fat-restricted diet. Seventy-nine subjects completed the six-month study; those on the low-carb diet lost more weight than those on the low-fat diet and had greater decreases in triglyceride levels. Insulin sensitivity also improved more among patients on the low-carb diet.

The second study (348:2082-90), led by Gary D. Foster, Ph.D., of the University of Pennsylvania School of Medicine, was a one-year, multicenter, controlled trial involving 63 obese men and women. Subjects assigned to a low-carb diet lost more weight than those on a low-fat diet, though the differences were not significant at one year. The low-carb diet was associated with greater improvement in some risk factors for coronary heart disease, including increased HDL cholesterol and decreased triglyceride levels.

Foster told The New York Times (www.nytimes.com) he was surprised by the results. "I went into this skeptical about the claims that the Atkins diet was safe, and now I'm more open-minded," he said. "Low-carbohydrate diets are a potentially viable option that needs more testing." Foster and colleagues are currently enrolling participants for a large, National Institutes of Health-funded, five-year study comparing low-carb and low-fat diets in 360 participants.

The study results did not come as a surprise to proponents of the Atkins diet. "I'm thrilled that serious researchers are taking a hard look at the program, so that health care professionals and physicians would find comfort in offering Atkins as an alternative to the one-size-fits-all hypothesis of low-fat, low-calorie," Collette Heimowitz, director of education and research at Atkins Health & Medical Information Services (www.atkins.com), told the Times. The diet has proven extremely popular in recent years. On this week's Times book lists, Dr. Atkins' New Diet Revolution was No. 1 on the paperback "advice" list (in its 310th week), while Atkins For Life was the top seller on the hardcover "advice" list (15 weeks on the list).

However, other organizations cautioned consumers not to give up their carbs. The American Dietetic Association (ADA) issued a release stating the two studies show there is no "magic bullet" for weight loss and, in the long-term, success rates were similar among diets. ADA (www.eatright.org) noted the results show individuals can move toward a higher protein intake for weight management, maintaining lower fat intakes and ensuring complex carbohydrates are the primary carbs ingested.