The obesity epidemic across the Western world could trigger an epidemic of dementia, doctors have warned.

Obese people with a body mass index of at least 30 have a 74% increased risk of developing degenerative brain diseases including Alzheimer’s later in life, researchers have found.

Among the overweight with a body-mass index of over 25 the risk of dementia is increased by 35%, as The Independent reported today.

The proportion of the British adult population who are obese has grown from 6% in 1980 to 22%, and is still on the increase.