Omega-3 supplements may only support short term weight loss: Study

11-Jan-2012 - Last updated on 11-Jan-2012 at 12:41 GMT

Supplementation with omega-3 fatty acids may lead to reductions of body fat for obese people, but is only effective over short time frames, according to new research.

The study – published in the British Journal of Nutrition – investigated whether long-chain omega-3 polyunsaturated fatty acids (PUFAs), combined with a very-low-energy diet (VLED), assisted with weight loss and maintenance and improved blood lipids and inﬂammatory mediators in obese people.

Led by Professor Manohar Garg of the Nutraceuticals Research Group at the University of Newcastle, Australia, the research team found supplementation of omega-3 six times per day (each consisting of 70mg EPA and 270mg DHA) resulted in weight loss only up to the 14th week of testing.

“Both groups experienced improved metabolic proﬁles and there was a signiﬁcant reduction in fat mass for the fish oil group at week 14 but not for placebo,” explained Garg and his colleagues.

“However, it would appear that supplementation with long chain omega-3 PUFA had no signiﬁcant effect on weight loss or weight maintenance over the 14 weeks,” they revealed.

As a result, Garg and his co-workers said the potential benefits of loading cells and cell membranes with omega-3 fatty acids before the implementation a weight loss programme “merits further examination.”

Research highlights

The researchers gave a group of 40 men and women either a placebo or a supplement containing a 4:1 ratio of DHA and EPA omega-3 fatty acid six times a day in a double blind randomised controlled trial.

“The main purpose of the present study was to investigate whether long chain omega-3 PUFAs would assist weight loss when administered as a supplement during a weight loss diet,” explained Garg and his team.

“To this end, it was essential that the diet was controlled and participant energy intake was as similar as possible to enable the measurement of the effect,” they said.

The team reported that short-term supplementation with fish oil improved the metabolic profile of the participants for the duration of the study, but had little influence on weight loss.

They noted that there was a significant decrease in fat mass for the fish oil group during the first 14 weeks of the trial, however, when compared to the placebo group, the difference was modest, said the researchers.

“While it is possible that this difference in fat mass could be attributed to supplementation with long chain omega-3 PUFAs, a larger cohort of subjects would be required to determine the significance with such modest changes,” warned Garg and his colleagues.

Source: British Journal of Nutrition
Published online ahead of print, doi: 10.1017/S0007114511006817
“Dietary supplementation with n-3 PUFA does not promote weight loss when combined with a very-low-energy diet”
Authors: I.A. Munro, M.L. Garg