Holistic approach to dementia is needed

We need ‘increasing investment to maintain and develop our cultural resources.’ Photograph: Peter Macdiarmid/Getty ImagesIt is refreshing to see an article about the effects of social activity in preventing dementia on the front page of the Guardian (Social life may lower the risk of dementia, 3 August). The sad fact is that this has been known for many years, including examples such as the Nun Study, which examined the effects of ageing on a group of Roman Catholic nuns in the Unite