Eating a diet rich in omega-3 oils, fruits and vegetables may lower the risk of dementia and Alzheimer's Disease, researchers say.
Experts examined the diets of more than 8,000 men and women aged over 65 years who did not have dementia at the beginning of the four-year study.
Participants who regularly ate omega-3 rich oils such as flaxseed and walnut oil had a 60% lower risk of developing dementia than those who did not.
Eating fruits and vegetables every day also reduced the risk of developing dementia by 30%.
Those who ate fish at least once a week had a 35% lower risk of Alzheimer's Disease and a 40% reduced chance of dementia, but only if they did not carry the gene that increases the risk of Alzheimer's.
Study author Pascale Barberger-Gateau said: "Given that most people do not carry the ApoE4 gene, these results could have considerable implications in terms of public health.
"However, some research is needed to identify the optimal quantity and combination of nutrients which could be protective before implementing nutritional recommendations."