The key marine omega-3 fatty acids are docosahexaenoic acid (DHA) and eicospentaenoic acid (EPA). Both produce a series of important metabolites important for good cell health, but DHA specifically is incorporated into the cell membrane of neural tissue. A recent study of the distribution of omega-3 fatty acids in the bodies of rats showed that the brain and testes contained a total of 12% and 15.6%, respectively, of the total DHA (2).
Using rats, Professor Eckert’s team demonstrated that supplementation with fish oil for three weeks could restore the mitochondrial function lost as the rats age i.e., respiration rates and ATP production were increased (3). They were also able to show using isolated cell membrane fractions that the fish oil was also able to partially improve membrane fluidity. Finally, they noted increases in the anti-apoptotic protein Bcl-2 and neuroprotection D1 (NPD1), a powerful neuroprotective metabolite of DHA produced by lipoxygenase oxidation (4).
In 2014, Witte et al. (5) conducted a double blinded clinical trial on a small cohort (n=65) of health elderly people aged between 50 to 75 years with an intervention of 2.2g fish oil per day for 26 weeks to determine if there was an improvement in cognition. They found significant benefits in cognition and also beneficial effect to the structure of the brain, namely white matter microstructural integrity and grey matter volume in the temporal, parietal and limbic areas.
A recent meta-analysis (6) showed that DHA alone, or in combination with EPA, was associated with improved episodic memory in adults with mild memory complaints. Specifically, episodic memory was significantly improved with a daily intervention of 1g or more day of DHA and EPA.
Professor Eckert’s team (1) concluded that “our findings provide new mechanisms underlying the neuroprotective actions of polyunsaturated fatty acids and underscore the impact of fish oil as a promising nutraceutical to delay age-related cerebral alterations”.