Fish Oil Didnt Up Weight Loss

DALLASFish oil capsules did not accelerate weight loss or change metabolic factors in overweight individuals who were already dieting and excising in a recent study published in the American Journal of Clinical Nutrition (2010 Dec 15). Those who received the omega-3 pills lost more than 5 percent of their body weight, but so did those who received placebo pills.

In a single-institution, placebo-controlled, randomized clinical trial, 128 individuals with a body mass index (BMI) between 26 and 40 were assigned to receive 5 omega-3 [3.0 g eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) at a 5:1 ratio (EPA:DHA)] or placebo capsules daily in conjunction with lifestyle modification. The primary endpoint was weight loss; secondary endpoints included metabolic and psychometric variables.

Researchers led by Laura F DeFina of the The Cooper Institute, Dallas, assigned overweight and obese individuals to the omega-3 arm (n=64) or to the placebo arm (n=64). Subjects in both arms received dietary and exercise counseling. Participants were instructed to do 150 minutes a week of aerobic exercise and 20 to 30 minutes of strength exercises at least twice a week.

 Eighty-one individuals completed the 24-week study, and the dropout rate was 27 percent. Subjects in both arms lost an average of more than 5 percent of their body weight. No significant differences in weight loss were observed between the omega-3 (−5.2 kg) and placebo (−5.8 kg) arms. The absolute mean (±SEM) change difference was 0.61 ± 0.58 kg (P = 0.29). In addition, no significant differences in the other factors assessed were observed, such as measures of heart disease risk like blood pressure and cholesterol levels. However, omega-3 blood levels in the fish oil group increased to a level "previously found to have a positive cardiovascular effect," the researchers noted.