In blood, the ratio between EPA and pro-inflammatory arachidonic acid (or EPA/AA) and the Omega-3 Index are proportional to dietary intakes of omega-3 fats. However, many American diets are recognized as providing generous amounts of AA relative to omega-3 fats, and lower blood levels of EPA and DHA (docosahexaenoic acid) constitutes a risk factor for cardiovascular disease.
Nutrition research is discovering mechanisms by which dietary EPA and DHA benefit body function, ranging from cognition and skin and eye health to musculoskeletal comfort and immune balance. A number of studies have converged upon ways EPA and DHA influence immune-related messaging among cells, and suggest that this immune-mediated signaling may underlie many of the observed advantages of omega-3 fat supplementation.
In this clinical trial, researchers provided 1.8 g EPA or placebo daily to 82 obese individuals, who also showed elevated triglyceride levels and/or reduced HDL-cholesterol levels, for a period of three months. Study subjects were tested for nutritional, metabolic, immune, and cardiovascular parameters before and after intervention. In a separate lab study, monocytes immune-triggered by exposure to toxic lipopolysaccharides (LPS) were subsequently exposed to EPA to observe effects on levels and genetic expression of IL-10.
EPA Supplementation Improves IL-10 Levels and Immune Genetic Expression
Excess Adiposity is Marked by Immune Imbalance
In obesity, adipose tissues contain reduced levels of omega-3 fatty acid metabolites. This metabolic imbalance is reflected by a predominance of pro-inflammatory M1 macrophages over anti-inflammatory M2 macrophages, accompanied by reduced genetic expression of the pivotal immunomodulator IL-10. EPA supplementation may represent a meaningful way of improving IL-10 expression.