Effects of fish oil on cognitive function
A: The brain contains many essential fatty acids. These fatty acids are important for neuronal function, so they may have a protective effect against cognitive impairment.
Omega-3 fatty acids have to be consumed in the diet as they cannot be made in humans. Oily fish are a good source.
A Cochrane Review has considered placebo-controlled trials of supplements of omega-3 fatty acids for preventing cognitive decline in people over 60 years old. The participants did not have any evidence of dementia at the start of the studies.