Lifestyle change and the prevention of cognitive decline and dementia: what is the evidence?

Purpose of review Effective pharmaceutical treatment of dementia is currently unavailable. Epidemiological work has, however, identified modifiable lifestyle factors, such as poor diet and physical and cognitive inactivity, that are associated with the risk of dementia. These factors may be useful targets for the prevention of cognitive impairment and dementia. Much recent research has, therefore, adopted an interventional focus. We review this work, highlight some methodological limitations, and provide recommendations for future research. Recent findings Change from a sedentary lifestyle to moderate physical activity has beneficial effects on cognitive functioning, and preliminary evidence suggests that such change may reduce the incidence of dementia. The evidence on cognitive benefits of lifestyle changes towards more intellectual engagement is insufficient. Nutritional supplements to treat deficiency may improve cognitive performance, but supplements on top of a healthy diet cannot be recommended. Summary Introduction of physical activity can reduce the risk of cognitive impairment in old age. Future research on nutritional supplements must consider the principle of an inverted U-shaped association between nutritional level and cognitive function. Work on the effects of cognitive training must use transfer tasks as primary outcome measures, and investigate whether effects of cognitive training generalize beyond the trained cognitive tasks.