Being underweight in middle age is associated with raised dementia risk, large study finds

People who are underweight in middle age are at increased risk of developing dementia, while increasing weight and obesity offer protection against the condition, a large cohort study has found.

A number of previous studies have looked at the association between weight and dementia, and most have found that the risk of dementia increased among adults who are overweight or obese, although some studies have found the opposite. Most of these studies have been small, which led the present researchers to conduct a much larger analysis of the link.

The researchers, from the London School of Hygiene and Tropical Medicine and from OXON Epidemiology, both based in London, examined the …