The largest study of its kind, involving over a quarter of a million people (267,000) from the UK Bio Bank, has reported 30 per cent less risk of dementia in those with a higher omega-3 status in their blood.
One of the study authors, Professor Bill Harris from Stanford University’s Department of Medicine in South Dakota, says “There is now overwhelming evidence from no less than four studies this year that increasing your intake and blood levels of omega-3 is strongly associated with reducing future dementia risk. Ideally a person wants to get their blood omega-3 index above 8%”.
This UK study confirmed the results of a US study earlier this year that found a 49 per cent reduced risk for dementia in those with the highest omega-3 DHA level (top fifth) in their red blood cells versus the lowest (bottom fifth). Oily fish and fish oil supplements contain two kinds of omega-3 fat called DHA and EPA. DHA is the main fat found in brain cells of all animals.
What’s more a meta-analysis of 48 studies in the American Journal of Clinical Nutrition in 2023 also concludes that ‘a moderate-to-high level of evidence suggested that dietary intake of omega-3 fatty acids could lower risk of all-cause dementia or cognitive decline by about 20 per cent, especially for DHA intake’.
A recent study by psychologists at the Linda Loma University in California and published in the journal Brain Sciences, reported that the higher a person’s omega-3 index was in their blood, the more white matter there was in their brain meaning they had more brain volume, and the better they performed on cognitive tests that predict less risk for dementia.