Health or Hype: Diet research reveals the best diets for weight loss and disease prevention!

Photo: Bensonkua

Diets make claims all the time about how much weight you'll lose, how great you'll feel and most recently, how flat your abs will be if you follow their every rule.  Diets claims are rarely backed-up with cold, hard science; however, some diets are finally being evaluated on their short-term success.  Here's a round-up of research study results and what they mean for your efforts to lose weight and be healthier!

Prevent Cardiovascular Disease

Diets Tested:  The… New Glucose Revolution, Atkins Diet, South Beach Diet phases two and three, Dean Ornish Eat More, Weigh Less, Zone, Weight Watchers, USDA 2005 Food Pyramid.

Methodology:  This study did an analysis of all the above diets to determine which would be the most effective in preventing heart disease if you followed each plan perfectly.

Results: Dean Ornish's Diet came in first (largely due to being vegetarian).  Second and third went to Weight Watchers and The Glucose Revolution respectively.  Despite claims to the contrary, this study ranked the Atkins diet in last place.  Want to get started?  To find a Weight Watchers meeting in the Des Moines area - click here! 

Real Life:  If heart disease runs in your family this study suggests that a vegetarian diet similar to Dean Ornish's plan might give your heart the best protection, while the meat-heavy Atkins diet seems like a poor choice.

Journal of the American Diabetic Association.  Oct. 2007 "A Dietary Quality Comparison of Popular Weight-Loss Plans" by Yunsheng Ma, MD, PhD, et al.

Weight Loss by Gender Over Two Years

Diets Tested:  Low-carb, Mediterranean and low-fat

Methodology:  This study looked at 300 moderately obese subjects and assigned them to one of the three diets for two years.

Results:  After two years the group following the low-carb and the Mediterranean diets were greater than the group with the low-fat diet.  Interestingly women lost the most weight on the Mediterranean diet, while the men lost the most weight on the low-carb diet.

Real Life:  Low fat diets were popular in the 90's, but now it seems clear that they are not the most effective eating plan for weight loss.  Eating 20 - 30% of your calories from heart-healthy fats has been shown to aid in weight loss, and eating healthy fats may help you feel satisfied.  In addition, eating fat-free foods has been shown to inhibit weight loss in recent studies as well.  Look for foods with heart healthy mono and poly unsaturated fats in them to include in your daily diet.

The New England Journal of Medicine.   July 17, 2008.  "Weight Loss with a Low-Carbohydrate, Mediterranean or Low-Fat Diet." by Iris Shai, R.D., PhD, et al. 

Which diet is Easiest to Stick To, and Results in the Most Weight Loss Over One Year

Diets Tested:  Atkins Diet, Dean Ornish Eat More, Weigh Less, Weight Watchers or Zone diets

Methodology:  160 overweight individuals were assigned to one of the five diets and asked to stick with it for a year.

Results:  After the year, 25% of the individuals who stuck to their assigned diet had lost more than 5% of their body weight.  There were no significant differences in the amount of weight lost between the plans.  Participants on the Zone and Weight Watchers were the most likely to stick to their plan, which the study concludes is far more important than which diet individuals choose. 

Real Life:  Since this study suggests it doesn't matter which diet you choose to follow, choosing a diet with matches your lifestyle and eating patterns can help you be more successful.  Consult a website such as Web MD, which has information on nearly every known diet, and can help gets the facts on different plans.  Good Housekeeping also has a great diet comparison tool to help you find the perfect plan.

The Journal of the American Medical Association.  Jan. 5, 2005.  "Comparison of the Atkins, Ornish, Weight Watchers, and Zone Diets for Weight Loss and Heart Disease Risk Reduction"
by Michael L. Dansinger, et al.