New research suggests that people with mild cognitive impairment (MCI) are at higher risk of developing dementia if they have diabetes or psychiatric symptoms such as depression.

Researchers at the University College London found that among people with MCI, those with diabetes were 65 percent more likely to progress to dementia and those with psychiatric symptoms were more than twice as likely to develop the condition.

MCI is a state between normal ageing and dementia, where someone's mind is functioning less well than would be expected for their age. It affects 19 percent of people aged 65 and over, and around 46 percent of people with MCI develop dementia within 3 years compared with 3 percent of the general population.

"There are strong links between mental and physical health, so keeping your body healthy can also help to keep your brain working properly," Dr. Claudia Cooper, lead author of the study, said in a statement. "Lifestyle changes to improve diet and mood might help people with MCI to avoid dementia, and bring many other health benefits. This doesn't necessarily mean that addressing diabetes, psychiatric symptoms and diet will reduce an individual's risk, but our review provides the best evidence to date about what might help."

The Alzheimer's Society charity recommends that people stay socially and physically active to help prevent dementia. Their guidelines also suggest eating a diet high in fruit and vegetables and low in meat and saturated fats, such as the Mediterranean diet.

"Some damage is already done in those with MCI but these results give a good idea about what it makes sense to target to reduce the chance of dementia," said Professor Gill Livingston, senior author of the study. "Randomized controlled trials are now needed."

The findings are detailed in the American Journal of Psychiatry.