Dementia risk can be cut with drinking less alcohol and cutting risk of type 2 diabetes, new research suggests

40 per cent of dementia cases are potentially preventable, Dr Susan Mitchell, at Alzheimer’s Research UK

Some 161 risk factors for dementia were examined in the new study (Joe Giddens/PA) (PA Wire)

Drinking less alcohol and reducing the risk of type 2 diabetes could help people cut their chances of dementia, new research suggests.

Limiting exposure to traffic-related air pollution could also reduce the risk of developing the condition, according to the study.

It has been suggested that the findings could also help explain why certain groups may be more vulnerable to dementia.

Scientists have previously identified a weak spot in the brain, a specific area that develops later during adolescence and also shows earlier degeneration in old age.

In the new study, 161 risk factors for dementia were examined, and ranked according to their impact on this brain network, over and above the natural effects of age.

The researchers, at the University of Oxford, classified these so-called modifiable risk factors – things people can do something about, like cutting down drink or sugar – into 15 broad categories.

These were blood pressure, cholesterol, diabetes, weight, alcohol consumption, smoking, depressive mood, inflammation, pollution, hearing, sleep, socialisation, diet, physical activity, and education.

The findings suggest that alcohol intake, diabetes and traffic-related air pollution are the most harmful.

According to Diabetes UK, the main things someone can do to lower their chance of developing type 2 diabetes is to eat more healthily and lose weight if needed.

In a study published in Nature Communications, researchers investigated the genetic and modifiable influences on these brain regions by looking at the brain scans of 40,000 people in the UK Biobank database aged over 45.

Professor Gwenaelle Douaud, who led the study, said: “In this new study we have shown that these specific parts of the brain are most vulnerable to diabetes, traffic-related air pollution – increasingly a major player in dementia – and alcohol, of all the common risk factors for dementia.

The study analysed the unique contribution of each controllable risk factor by looking at all of them together to assess the resulting degeneration of this particular brain weak spot.

Professor Anderson Winkler, a co-author from the National Institutes of Health and the University of Texas Rio Grande Valley in the US, said: “It is with this kind of comprehensive, holistic approach – and once we had taken into account the effects of age and sex – that three emerged as the most harmful: diabetes, air pollution, and alcohol.”

Dr Susan Mitchell, head of policy at Alzheimer’s Research UK, said: “With no treatments yet available in the UK that can stop or slow the diseases that cause dementia, there has never been a more pressing need to promote good brain health and to gain a deeper understanding on how dementia can be prevented.

“It’s generally accepted that up to 40 per cent of dementia cases are potentially preventable, so there is an enormous opportunity to reduce the personal and societal impact of dementia.”

She said the findings, based on retrospective analysis of brain scans and data from 40,000 people will help shed light on this issue further.

“The results will need confirming, both in forward-looking studies that follow participants over time, and in a more diverse study population. But they could help explain why certain groups may be more vulnerable to dementia – such as those living in highly polluted areas,” Dr Mitchell added.