New guidance from the American Diabetes Association gives a green light to the use of low-carbohydrate diets as a weight-control measure for patients with diabetes.

As part of the ADA's annual update of its clinical practice recommendations, the organization has dropped its formerly restrictive stance on low-carbohydrate diets.

The updated guidelines for 2008 also revise recommendations on prediabetes testing, metformin use, and hypoglycemia prevention, among other topics.

Although the ADA still does not endorse low-carbohydrate diets for weight loss or diabetes management, the association has updated the section of its guidelines that covers nutrition recommendations and interventions for diabetes to remove a specific recommendation against diets that restrict carbohydrates to less than 130 g/day. Now, for weight loss, the ADA says that either low-carbohydrate or low-fat calorie-restricted diets might be effective in the short term (up to 1 year). Previous language that recommended against low-carb diets was also removed from the 2008 section on nutrition recommendations for managing diabetes (secondary prevention).

For patients who are on low-carbohydrate diets, the ADA now advises monitoring of lipid profiles, renal function, and protein intake (in patients with nephropathy), as well as adjustment of glucose-lowering as needed (Diabetes Care 2008;30[suppl. 1]:S61–78).

“The evidence is clear that both low-carbohydrate and low-fat calorie-restricted diets result in similar weight loss at 1 year. We're not endorsing either of these weight-loss plans over any other method of losing weight. What we want health care providers to know is that it's important for patients to choose a plan that works for them, and that the health care team support their patients' weight loss efforts and provide appropriate monitoring of patients' health,” guideline panel member and registered dietician Ann Albright, Ph.D., ADA President of Health Care and Education, said in a statement.

New data cited in the 2008 document are from the A to Z Weight Loss Study, a randomized trial that compared the Atkins, Zone, Ornish, and LEARN (Lifestyle, Exercise, Attitude, Relationships, and Nutrition) diets in a total of 311 overweight premenopausal women. At 1 year, the Atkins diet group showed significantly more weight loss (-4.7 kg) than did the other three diet groups (-1.6 kg with Zone, -2.6 kg with LEARN, and -2.2 kg with Ornish). Secondary outcomes, including lipid profile, percentage of body fat, waist-hip ratio, fasting insulin and glucose levels, and blood pressure, were comparable or better with Atkins versus the other diet groups (JAMA 2007;297:969–77).