Acides gras oméga-3 et déclin cognitif : la controverse

Basic research suggests a protective effect of the long-chain omega-3 polyunsaturated fatty acids - eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) - against brain aging. In humans, many epidemiological studies have found an inverse association between fish consumption or high blood levels of EPA and DHA, and cognitive decline or risk of dementia. However, most randomized controlled trials with EPA and/or DHA supplements have failed to show any impact on cognitive decline. This paper analyses several reasons for such inconsistent results, including the time and duration of the supplementation, the cognitive and dietary inclusion criteria, the optimal doses of EPA and DHA, the interaction with genetic polymorphisms, and the need to consider synergistic effects between nutrients as they are provided by healthy diets.