Omega-3 supplements or fish oil has been in the health spotlight for multiple reasons, from preventing obesity to curing schizophrenia. However, the latest on the fish oil scoreboard is not good news.
WHAT DO WE KNOW ABOUT OMEGA-3 SUPPLEMENTS AND BRAIN HEALTH?
Omega-3 fatty acids are a group of polyunsaturated fatty acids considered to be good fats. These are generally found in fatty fish, shellfish, and vegetable oils, but are mostly taken as commercially available omega-3 supplements. According to a 2007 National Health Interview Survey, omega-3/fish oil supplements ranked first among the most common non-vitamin dietary supplements. Omega-3 fatty acids are known to play a role in brain and eye function. Particularly, their effects on staving off cognitive decline have been proclaimed ad nauseam.
CLINICAL TRIAL TESTED COMMON NOTION THAT FISH OIL BOOSTS BRAIN FUNCTION
Observational data suggests that high intake of saturated fats and low intake of vegetables could pose an increased risk for cognitive decline seen in Alzheimer’s disease. The clinical trial was designed to test the hypothesis that fish oil supplements prevent cognitive decline. Led by Emily Chew M.D., deputy clinical director at the National Eye Institute (NEI), this study was one of the longest and largest to address the issue. A total of 4203 participants were recruited for this 5-year old study called the Age-Related Eye Disease Study 2 (AREDS2). Participants at risk for developing age-related macular degeneration⎯an eye disease that causes vision loss⎯were recruited. They were also administered standardized cognitive tests at baseline and every 2 years during the study period.
FISH OIL SUPPLEMENTS DO NOT PREVENT COGNITIVE DECLINE
Participants were randomly assigned to receive omega-3 supplements, nutrients found in vegetables, a combination of the two, or placebo pills. When the cognitive scores were compared between treatment groups, all participants showed similar rates of cognitive decline over the study period. Not a single combination of supplements performed better than the placebo. This debunks the commonly held notion that fish oil pills help with memory and brain function. This study reinforces the need to conduct long-term, population-wide studies before purporting the beneficial effects of dietary supplements on brain health.
