Higher-protein Diet May Be Better for Weight Loss, Cholesterol

MIAMI--Researchers at the Agatston Research Institute conducted a randomized trial involving 60 participants (29 women and 31 men), aged 28 to 71 years, to examine the effects of consuming either the U.S. National Cholesterol Education Program (NCEP) diet or a protein and monounsaturated fat (MLC) diet [isocaloric modified low carbohydrate, which is lower in total carbohydrates but higher in protein, monounsaturated fat, and complex carbohydrates]. Participants were evaluated every two weeks for 12 weeks.

Thirty-six percent of the NCEP participants and 35 percent of the MLC participants had a body mass index (BMI) greater than 27. The primary end point studied was weight loss; secondary end points were blood lipid levels and waist-to-hip ratio.

Weight loss was significantly greater in the MLC (13.6 pounds) group than in the NCEP group (7.5 pounds). No significant differences were found between groups for total, low density (LDL), and high density lipoprotein cholesterol (HDL); triglycerides; or the proportion of small, dense LDL particles. There were significantly favorable changes in all lipid levels within the MLC group, but not within the NCEP group. Waist-to-hip ratio was not significantly reduced between the groups; however, the ratio was significantly decreased within the MLC group.

The researchers concluded in comparison with the NCEP diet, the MLC diet--which is lower in total carbohydrates, but higher in complex carbohydrates, protein and monounsaturated fat--caused significantly greater weight loss over a 12-week period. Favorable blood lipid level changes also were observed within the MLC group.

The study was published in the October issue of the Archives of Internal Medicine 164, 19:2141-2146, 2004 (http://archinte.ama-assn.org/).