Alzheimer’s and dementia may be a result of the Western diet, new research suggests.  People who eat a diet that’s rich in fish, omega-3 oils, fruits and vegetables are up to 60 per cent less likely to develop Alzheimer’s – whereas people who consume large amounts of omega-6 oils, such as sunflower and grape seed, double their chances of suffering dementia.
It’s reckoned that the omega-3/omega-6 imbalance in the processed and fast-food diet of the West is so out of kilter that people on average are consuming 30 times more omega-6 than is good for them.
Diet has been highlighted as the main factor in determining whether we enjoy our ful mental capabilities until the end.  A French study tracked the diet and progress of 8,085 men and women over the age of 65 who did not have dementia at the beginning of the trial. In the four years’ follow-up, 183 of the participants developed Alzheimer’s and a further 98 had dementia. 
The researchers found that people who regularly consumed omega-3 oils, such as canola oil, flaxseed and walnut, reduced their risk of dementia by 60 per cent compared to those who do not regularly consume the oils.  People who ate fruits and vegetables every day reduced their risk of dementia by 30 per cent.
(Source: Neurology, 2007; 69: 1921-30).