Fish Oil Impresses in Body Composition Trial

Consumer will undoubtedly link fish oil to heart health in today’s market, but new research published today at the Journal of the International Society of Sports Nutrition suggests a potential for weight management with the nutrient.

Researchers at Gettysburg College in Pennsylvania sought to investigate the changes fish oil consumption could have on factors related to body composition, including lean mass, fat mass, and cortisol levels. In the double-blind study, 44 subjects were assigned to 4 g of safflower oil or 4 g of fish oil (1600 mg of EPA and 800 mg of DHA) daily for six weeks. Biomarkers were measured at baseline and six weeks into treatment.

Supplementation with the fish oil proved to significantly increase lean mass and reduce fat mass when compared to safflower oil. A “tendency” towards a decrease in body fat percentage was also observed in the fish oil group.

Levels of cortisol, a hormone that becomes active during times of stress, were also recorded in the study. (The authors note that several studies have linked high cortisol to high fat mass.) Fish oil consumption resulted in an overall tendency for cortisol decrease compared to safflower oil consumption, but post scores in the fish oil group were significantly lower than baseline scores.

The researchers also identified a significant negative correlation between cortisol and lean mass.

“The results of this study showed that six weeks of supplemental fish oil significantly increased lean mass, and significantly reduced fat mass in healthy adults,” concluded the authors of the study.

Funding for the study was provided by a Gettysburg College Research and Professional Development grant. Fish oil was provided by Genuine Health Corp. (Toronto, ON).

To access a PDF of the full study, click here.