Health Advantages and Disadvantages of Weight-Reducing Diets: A Computer Analysis and Critical Review
James W. Anderson, MD, FACN, Elizabeth C. Konz, MS, RD, David J. A. Jenkins, PhD, MD, FACN
Metabolic Research Group, Veterans Affairs Medical Center; Department of Internal Medicine, College of Medicine, and Graduate Center for Nutritional Sciences, University of Kentucky, Lexington, Kentucky (J.W.A., E.C.K.),Clinical Nutrition & Risk Factor Modification Center, St. Michael’s Hospital, Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, CANADA, (D.J.A.J.) E-mail: jwandersmd@aol.com
Background: Some weight-loss diets are nutritionally sound and consistent with recommendations for healthy eating while others are “fad” diets encouraging irrational and, sometimes, unsafe practices.
Objective: The purpose of the study was to compare several weight loss diets and assess their potential long-term effects.
Design: Eight popular weight-loss diets were selected (Atkins, Protein Power, Sugar Busters, Zone, ADA Exchange, High-Fiber Fitness, Pritikin and Ornish) to be non-clinically analyzed by means of a computer to predict their relative benefits/ potential harm. A summary description, menu plan and recommended snacks were developed for each diet. The nutrient composition of each diet was determined using computer software, and a Food Pyramid Score was calculated to compare diets. The Mensink, Hegsted and other formulae were applied to estimate coronary heart disease risk factors.
Results: Higher fat diets are higher in saturated fats and cholesterol than current dietary guidelines and their long-term use would increase serum cholesterol levels and risk for CHD. Diets restricted in sugar intake would lower serum cholesterol levels and long-term risk for CHD; however, higher carbohydrate, higher fiber, lower fat diets would have the greatest effect in decreasing serum cholesterol concentrations and risk of CHD.
Conclusions: While high fat diets may promote short-term weight loss, the potential hazards for worsening risk for progression of atherosclerosis override the short-term benefits. Individuals derive the greatest health benefits from diets low in saturated fat and high in carbohydrate and fiber; these increase sensitivity to insulin and lower risk for CHD.