French researchers have found that elderly adults who regularly ate fish and other seafood were less likely than others to develop dementia--including Alzheimer's disease--over the next 7 years. Those who ate fish or seafood at least once a week were 34% less likely than less-frequent fish eaters to develop dementia over 7 years.

The researchers followed more than 1,400 adults aged 68 and older for at least 2 to 7 years. The French researchers note that fish fatty acids could be involved in dementia risk by protecting vascular health--or, alternatively, by reducing inflammation in the brain.

"The 'protective' effect of weekly fish or seafood consumption was partly explained by higher education of regular consumers," Barberger-Gateau's team writes. A number of studies have suggested that people with higher education may be less vulnerable to memory loss and mental impairment as they age because they have what is called a greater "brain reserve."

Dementia has a number of underlying causes. Experts believe that age, genetics, lifestyle and environmental factors all contribute to Dementia and Alzheimer's. High cholesterol and high blood pressure have also been tied to Alzheimer's risk. And one form of dementia called vascular dementia results from an inadequate blood supply to the brain.

SOURCE: British Medical Journal 2002;325:932-933.