Earlier studies have shown that low levels of omega-3 fatty acids may be linked to both depression and to inflammation. A double-blind study appeared in Brain Behavior, and Immunity (epublished ahead of print July 19, 2011 doi:10.1016/j.bbi.2011.07.229); it looked at omega-3 fatty acid consumption, its effect on the production of inflammatory chemicals known as cytokines and its effect on depression. The subjects of the 12 week study were 68 medical students who were given either a placebo or an omega-3 fatty acid supplement containing EPA (2085 mg/day) and DHA (348 mg/day). Blood samples were taken regularly during periods of low stress as well as on days before an exam. The student who received the omega-3 supplement produced lower levels of the chemicals associated with inflammation. Compared to controls, those students who received the supplement had a 14% decrease in lipopolysaccharide (LPS) stimulated interleukin 6 (IL-6) production (a chemical that indicates the presence of inflammation) and a 20% reduction in anxiety symptoms, without significant change in depressive symptoms.
Because people vary in their ability to absorb essential fatty acids, blood tests were performed to look at the ratio between omega-3 fatty acids and omega-6 fatty acids in the blood. A higher ratio of omega-3 to omega-6 fatty acids was associated with decreased tumor necrosis factor alpha, another chemical that indicates the presence of inflammation.
The authors concluded, “The reduction in anxiety symptoms associated with omega-3 supplementation provides the first evidence that omega-3 may have potential anxiolytic benefits for individuals without an anxiety disorder diagnosis.”
