Elderly people who eat fish or seafood at least once a week are at lower risk of developing dementia, according to a recent study.

A team of French researchers questioned 1,674 people aged 68 and over without dementia about their eating habits to discover whether there was a relation between consumption of fish (rich in polyunsaturated fatty acids) or meat (rich in saturated fatty acids) and risk of dementia. Participants were followed up two, five, and seven years afterwards.

Participants who ate fish or seafood at least once a week had a significantly lower risk of being diagnosed as having dementia in the seven subsequent years.

When education was taken into account, the strength of the association was slightly reduced, suggesting that this "protective" effect was partly explained by higher education of regular consumers, say the authors.

As well as providing vascular protection, the fatty acids contained in fish oils could reduce inflammation in the brain and may have a specific role in brain development and regeneration of nerve cells, suggest the authors.