From Laura Dolson,
Your Guide to Low Carb Diets.
FREE Newsletter. Sign Up Now!

About.com Health's Disease and Condition content is reviewed by our Medical Review Board

In a 12-month, U.S. government-funded study conducted through Stanford University, the Atkins Diet beat out three other popular plans for weight loss, blood pressure reduction, and improvements in blood lipids (cholesterol, triglycerides). The other three diets were the Zone, Ornish, and something similar to the Food Pyramid. The participants in the study were 311 nondiabetic overweight or obese women, 20-50 years old.

The good news about this is that it is one more confirmation that low carb diets can be effective for weight loss, and that they are safe. In the media reports, this seems to have tipped the balance for some of the doctors in the news stories I've been reading about the study. Several of the doctors are quoted as saying that they will start suggesting to patients that reducing carbohydrates might be a helpful way to manage their weight.

The researchers attributed the success of Atkins to its being low in carbohydrates, but also that it is simple to follow - they characterized it as: basically stop eating sugary and starchy foods, and drink a lot of water. (Of course, other low carb diets such as Protein Power also have this message.)

Still, Atkins only won "by a nose". The participants in the study were checked at two, six, and twelve months. At the two and six month-marks, the Atkins group had lost significantly more weight than any of the other groups. However, all groups started to regain weight after an initial loss. At one year, the Atkins group had lost an average of 10½ lbs, which was about twice as much as the Ornish and traditional groups (which did not reach statistical significance) and three times more than the Zone group.

Criticisms of the Study

Barry Sears (of the Zone Diet) and Dean Ornish have both criticized the study because the participants didn't follow their programs very carefully. The researchers countered that the point of the study is that people followed the diets as they would in the "real world". Participants in the Atkins group did not follow that diet exactly either. A more interesting question to me is "Why didn't people follow the diets?" All the participants were required to go to a one-hour class each week for eight weeks to make sure they had learned how to do the diets correctly and receive some measure of support in the early phases of the diets.

More Details and Opinions About the Study, as We Try to Answer the question, "Why Wasn't There a Bigger Weight Loss?

Reference: Gardner, Christopher, Alexandre Kiazand, Sofiya Alhassan, et al. "Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal Women." Journal of the American Medical Association. 297/9 (2007)