More exercise, less food and cutting down on alcohol can all stave off dementia, a major new report suggests.
In its first-ever risk guidelines on the condition yesterday, the World Health Organisation said dementia was not inevitable and many people could avoid it with a change in lifestyle.
Long assumed to be just part of getting older, dementia is often seen a cruel twist of genetics and fate for some.
But while genes do play a role, the WHO said lifestyle can make a huge difference and around 35 per cent of cases are now thought to be influenced by factors that people can change.
‘Dementia is not a natural or inevitable consequence of ageing,’ the report said.
Recent studies had shown a link with risk factors such as physical inactivity, smoking, unhealthy diets and ‘harmful use of alcohol’.
People who were depressed, obese, or had high blood pressure, diabetes or high cholesterol were also more likely to get dementia.
Roughly 50million people around the world currently suffer from dementia, with 850,000 of them in Britain.
WHO head Dr Tedros Adhanom Ghebreyesus said: ‘In the next 30 years, the number of people with dementia is expected to triple. We need to do everything we can to reduce our risk.’
The report looked at 12 possible factors influencing cognitive decline and dementia. Depression had a huge effect, doubling the odds of dementia and with no evidence that antidepressants reduce the risk.
Obesity was also a major issue. Someone overweight in middle age was a third more likely to suffer dementia than a slim person.
Physical activity, stopping smoking, eating healthily and avoiding heavy drinking were also seen as important. Treatment for high blood pressure, high cholesterol and diabetes were shown to lower the odds of dementia, but vitamins and supplements did not – and high doses could even be harmful.
There was little evidence that ‘brain training’ or social activity helped.
WHO expert Neerja Chowdhary said there was some evidence of a link with pollution – but too little to include it in the recommendations.
Professor Robert Howard, an expert in old-age psychiatry at University College London, said: ‘We are probably decades away from treatments to slow or stop established dementia. Prevention would be so much better than a distant cure.’
Dr Carol Routledge of Alzheimer’s Research UK said only a third of adults knew they could cut the risk. She added: ‘Sadly, there will always be individuals who address many or all of these risk factors and still develop dementia. Genetic predisposition plays an important role in many people’s risk.
‘While we cannot change the genes we inherit, taking the steps outlined in this report can still help to stack the odds in our favour.’
Maria Carrillo of the US Alzheimer’s Association advised: ‘Start now. It’s never too late or too early to incorporate healthy habits.’
But Fiona Carragher of the Alzheimer’s Society said: ‘Every three seconds someone in the world develops dementia, and there’s still a lack of firm evidence on how exactly we should tackle the many risk factors.’