Yunsheng Ma, MD, PhD, and colleagues at the University of Massachusetts Medical School, Worcester, rated eight popular diet plans. The researchers chose one seven-day menu from each plan. They then ranked each menu according to seven dietary components most strongly linked to reducing heart disease risk.
Contenders, chosen because they are best-selling diet books, popular weight loss programs, or government recommendations, are the New Glucose Revolution, the Weight Watchers high-carb plan, the Weight Watchers high-protein plan, the Atkins Diet, the South Beach Diet, the Zone Diet, the Ornish Diet, and the 2005 USDA Food Guide Pyramid.
Dr. Ma, the envelope, please.
"We found the Ornish diet, the Weight-Watchers high-carb diet, and the and New Glucose Revolution rank high, but the Atkins Diet and the South Beach Diet rank low," Ma tells WebMD. "Surprisingly, the USDA diet is not high, but right in the middle."
First Place Goes to Ornish Diet
Scoring was based on seven dietary components that strongly affect heart disease risk: fruits, vegetables, nuts and soy, ratio of white to red meat, fiber, trans fat, and ratio of polyunsaturated fats to saturated fats. Each factor counted for a possible 10 points.
Out of a possible 70 points:
- The Ornish Diet was the winner with 64.6 points.
- The Weight Watchers high-carb diet got 57.4 points.
- The New Glucose Revolution diet got 57.2 points.
- The South Beach phase 2 diet got 50.7 points.
- The Zone Diet got 49.8 points.
- The 2005 Food Guide Pyramid got 48.7 points.
- The Weight Watchers high-protein diet got 47.3 points.
- The South Beach phase 3 diet got 45.6 points.
- The Atkins Diet's 45-gram-carbs plan got 42.3 points.
This is very encouraging news for Dean Ornish, MD, founder and president of the Preventive Medicine Research Institute in Sausalito, Calif., and clinical professor of medicine at the University of California, San Francisco.
"They really get it, they understand what is important for good nutrition," Ornish tells WebMD. "It is heartwarming -- in every sense of the word -- to read this."
What makes Ornish happiest is that Ma and colleagues focus on heart-disease prevention as the major reason for losing weight.
"There have been all these confusing studies that say people lost more weight on different diets. But more important is what happens to underlying heart disease," Ornish says. "This study is very consistent with our real findings. It is not just theoretical. Our diet doesn't just reduce risk factors, it reduces actual heart disease."
The Ma study gets a much worse review from South Beach Diet author Arthur Agatston, MD. Agatston, a cardiologist, is associate professor of medicine at the University of Miami and serves on the board of directors of the American Dietetic Association Foundation.
"It's pretty shoddy stuff," Agatston tells WebMD. "It is discouraging to say they base the paper on these principles of a heart-healthy diet that we were the first to emphasize in a popular book."
Agatston says there are thousands of South Beach Diet recipes and meal plans, and that it's unfair for Ma and colleagues to rate his entire diet on the basis of a single week's menu.
But what really irritates him, he says, is that the researchers give him a low ranking even though he stresses the same principles they do.
"To their credit, they do lay out good dietary principles for heart health -- but we were the first popular book to do that," Agatston says. "I am a cardiologist. For some nutritionists to plug something into a computer and say we are not heart healthy is a little bit silly. If they read my book, I am sure they'd agree."
Healthy Diet vs. Weight Loss Diet
Agatston, Ornish, and Ma all agree that the whole point of losing weight is to improve your health.
"It is not just about losing weight. The idea is to lose weight in a way that is helpful, not harmful," Ornish says. "If all you want to do is to lose weight, you can do it by smoking cigarettes or by going on amphetamines."
Ma says the point of the study is not to tell people to avoid any diet. Instead, he says people who want to lose weight should find a diet that works for them -- and then work with a nutritionist to gradually make heart-healthy changes.
"They can start with the Atkins Diet if they want to, but then they must make modifications and gradually add the good carbs and exchange bad fats for good fats," Ma says. "If people start out with a diet that they fail to follow, they will not lose weight -- and that is no good."
Ma and colleagues report their findings in the October issue of the Journal of the American Dietetic Association.