DEMENTIA risk has almost halved in 30 years as Brits adopt healthier lifestyles, research says.

Stopping smoking, eating well and keeping physically and mentally active have all helped slash the chance of developing the disease.

Millions of people also take statins and blood pressure tablets which protect heart and brain health. But the increase in obesity and diabetes rates may reverse the downward trend, experts fear.

The latest research analysed studies on nearly 60,000 adults across Europe and America between 1988 and 2015.

In that time, 5,133 developed dementia but rates plunged “around 15 per cent per decade”, the

Alzheimer’s Research UK Conference in Harrogate, North Yorks, was told.

Lead researcher Professor Albert Hofman, of America’s Harvard School of Public Health, said the findings were “positive”, and more pronounced in men than women.

He said the fall was “likely to be driven by changes in cardiovascular risk factors and lifestyle”.

But he warned: “With other dementia risk factors such as obesity and diabetes on the rise, this apparent decline in dementia rates may not continue for long.”

About 850,000 Brits have dementia with numbers expected to hit a million within a decade as people live longer.

There is no cure but drugs can limit its effects.

Dr Carol Routledge, of Alzheimer’s Research UK, said that while no drug could slow or stop Alzheimer’s, there was “robust evidence what’s good for the heart is also good for the brain”.

She added: “As well as maintaining a healthy blood pressure, the best current evidence suggests not smoking, only drinking within the recommended limits, staying mentally and physically active, eating a balanced diet, and keeping cholesterol in check can all help to keep our brains healthy as we age.”