Atkins? Diet Test Fails
The March 7, 2007 issue of Journal of the American Medical Association published the results of a 12-month study comparing the effects of 4 different weight loss diet strategies in overweight and obese (BMI = 27 to 40) pre-menopausal women. Researchers randomly assigned 311 women to follow one of the 4 diet programs.
First they read the Atkins, Ornish or Zone diet books or the LEARN Manual, which advocates a diet based on recent dietary guidelines, calorie restriction, exercise, and behavioral strategies. The same registered dietitian went over the 4 diet books/manual in 8 one-hour weekly group meetings. Blood values, blood pressure, and weight were checked at 2, 6, and 12 months.
Diet compliance was assessed by three 24-hour diet recalls done on 3 different days. Not surprisingly, compliance was better on all 4 diet plans during the first 2 months than in the last 6 months of the study. Compliance appeared best for the Atkins group who lost an average of about 4.5kg, while weight loss in the other 3 groups averaged between 2 and 3kg at the end of 2 months. Thereafter, compliance with all 4 diets deteriorated and weight changed little. At 12 months, the Atkins group still had lost significantly more weight than those assigned to the Zone diet. But this weight loss on the Atkins diet was no longer significantly lower than for those assigned to the Ornish or LEARN groups. This is because weight regained during the last 6 months was greater on the Atkins diet than the other 3 diets. The authors conclude ?...those assigned to the Atkins diet had more weight loss and more favorable outcomes for the metabolic effects at 1 year than women assigned to the Zone, Ornish, or LEARN diets.?1
Of course, the author?s own statistics show that the weight loss was not significantly less at 1 year on the Atkins diet than either the Ornish or LEARN diets. Certainly the drop in blood pressure was greatest in the Atkins group but it is well known that breads, cereals, and other starchy foods provide more salt than other food groups and the authors did not measure or report salt intake. The data show no significant difference between calories, fiber or protein intake at 12 months. They reported subjects consumed modestly more saturated fat and % fat on the Atkins diet than on the other 3 diets. However, the blood results showed no significant differences in LDL and non-HDL cholesterol levels. Since it is unlikely the proven hypercholesterolemic effect of saturated fat was not repealed for this study, maybe apparently the subjects? reported dietary intakes at the end of the study were more similar than reported during the 24 hour diet recalls. Diet recall can be biased by expectations and those on the 4 diets were supposed to be following their prescribed diet. Therefore, true compliance was likely even worse than the admittedly very poor reported compliance.
The results of this study should not be interpreted as demonstrating an Atkins diet high in saturated fat and cholesterol is healthier than a diet composed mainly of whole grains, fruits, and vegetables for improving blood lipids. It is also unlikely an Atkins diet is preferable for long term weight control. Certainly, long term compliance with the Atkin?s Diet would adversely impact blood lipids and promote cardiovascular disease. After all, Dr. Atkins died with advanced coronary artery disease, hypertension, and congestive heart failure and at a BMI of 35.2 Perhaps it is time the Atkins diet is laid to rest.
By James J. Kenney, PhD, RD, FACN
1 Gardner CD, et. al. Comparison of the Atkins, Zone, Ornish, and LEARN diets for change in weight and related risk factors among overweight premenopausal women. JAMA 2007;297:969-77
2 February 10, 2004, The Wall Street Journal, Report Details Dr. Atkins?s Health Problems, excerpts from the New York City Medical Examiner?s report on Atkins? death
The Best "Diet" For Life:
The most recent diet study showed that while people were able to lose a little more weight on the Atkin?s Diet initially, they gained it back before the study could be complete. One of the greatest dangers about the Atkin?s diet, or any diet that prohibits carbohydrates and emphasizes meat and fat, is that the diet is bad for your health. High-fat diets have been linked to certain cancers, heart disease and a greater incidence of obesity and diabetes.
The best diet is based on the DASH diet and MyPyramid.gov recommendations. It will allow you to have all the nutrients you need in the calories you are allotted each day.
Here is an overview for most people:
3-5 servings of whole grains each day
2.5 cups of vegetables each day
2 cups fruit each day
3 cups skim milk or fat-free yogurt each day
4-5 ounces lean protein each day
This diet is based on whole foods with fiber. It is limited in added fat and sugar, two food sources that are very dense in calories.
Judy’s passion for cooking began with helping her grandmother make raisin oatmeal for breakfast. From there she earned her first food service job at 15, was accepted to the world famous Culinary Institute of America at 18 (where she graduated second in her class), and went on to the Fachschule Richemont in Switzerland where she focused on pastry arts and baking. But after learning that the quality of a croissant directly varies with how much butter it has, Judy sought to challenge herself by coming up with recipes that were as healthy as they were tasty.
Judy received The Culinary Institute of America’s Pro Chef II certification, the American Culinary Federation Bronze Medal, Gold Medal, and ACF Chef of the Year. Her enthusiasm for eating nutritiously and deliciously leads her to constantly innovate and use the latest in nutritional science to guide her creativity, from putting new twists on fajitas to adapting Italian brownies to include ingredients like toasted nuts and cooked honey. Judy’s publishing company, Food and Health Communications, is dedicated to her vision that everyone can make food that tastes as good as it is for you.