Earlier studies have suggested that low levels of omega-3 fatty acids may be linked with both depression and inflammation. A double-blind study published in Brain, Behavior, and Immunity (epublished July 19, 2011; doi:10.1016/j.bbi.2011.07.229) examined omega-3 fatty acid supplementation, inflammatory markers known as cytokines, and mood. The 12-week study included 68 medical students who were randomly assigned to receive either a placebo or an omega-3 supplement providing EPA (2,085 mg/day) and DHA (348 mg/day). Blood samples were collected during periods of low stress as well as in the days leading up to major examinations. Students receiving the omega-3 supplement produced lower levels of inflammatory markers. Compared with the placebo group, they showed a 14% reduction in lipopolysaccharide (LPS)-stimulated interleukin-6 (IL-6) production, a marker of inflammation, and a 20% reduction in anxiety symptoms, while depressive symptoms did not change significantly.
Because individuals differ in their ability to absorb and utilize essential fatty acids, blood testing was used to measure the ratio of omega-3 to omega-6 fatty acids. A higher omega-3 to omega-6 ratio was associated with lower levels of tumor necrosis factor-alpha (TNF-α), another indicator 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.”
