A recent study conducted at UC found that a low carbohydrate (Atkins) diet was more effective than a low fat, calorie-controlled diet for short-term weight loss. The study, published in the April issue of the Journal of Clinical Endocrinology and Metabolism, also found that the low carbohydrate diet, which tends to be high in fat, was not associated with harmful effects on heart disease risk factors, such as increases in cholesterol or blood pressure.
Principal investigator, Bonnie Brehm, PhD, RD, assistant professor in the UC College of Nursing, was "definitely surprised by these unexpected results." Although the results are quite interesting, Dr. Brehm states that the study produced more questions than answers. She cautions that this study is a short-term study with a relatively small sample size. "More research must be conducted to determine long-term effects of the low carbohydrate diet among larger and more diverse populations, such as persons with diabetes, heart disease, and other chronic diseases."
In the study, 53 obese, but otherwise healthy women followed either a low carbohydrate diet or a calorie-restricted diet with 30 percent of the calories as fat for six months. The subjects met with a registered dietitian weekly for the first three months of the study; they then followed the diet for another three months, but without any contact with the dietitians or researchers.
Women on both diets reduced calorie consumption by similar amounts at three and six months. The low carbohydrate diet group lost more weight (18.7 lbs. vs. 8.6 lbs.) and more body fat (10.6 lbs. vs. 4.4 lbs.) than the low-fat diet group. Blood pressure, cholesterol, fasting glucose, and insulin levels improved similarly in both groups throughout the study. Other UC College of Medicine faculty involved in this research included Randy Seeley, PhD, assistant professor, psychiatry; Stephen Daniels, MD, PhD, professor, pediatrics; and David D'Alessio, MD, associate professor, endocrinology. Grants from the American Heart Association, UC Obesity Research Center, UC Research Council, and the National Institutes of Health supported their work.