A survey of 14,960 adults over the age of 65 in China, India, Cuba, the Dominican Republic, Mexico, Peru and Venezuela has found that (apart from in India) higher fish consumption was associated with a lower risk of developing dementia. The protective effect of fish is thought to come from Omega-3 fats which protect nerve cells, limit inflammation and help prevent the build up of damaging amyloid protein. The link between fish and a lower dementia risk held true even when other factors such as income, education, smoking and fruit and vegetable consumption were taken into account. Higher meat consumption was associated with a somewhat higher prevalence of dementia. The research was led by Dr Emiliano Albanese of King's College London.
You can find out more about this study at