PILING on the pounds in your thirties more than triples the risk of dementia later in life, experts warned last night.
Researchers from Oxford University have found that early to mid-life obesity is linked to an increased chance of developing the condition.
In a study of hospital records, overweight people aged 30 to 39 had a 3.5 times higher risk than people the same age who were of normal weight.
However, for those in their 40s the risk fell to 70 per cent; in their 50s to 50 per cent and for those in their 60s to 40 per cent.
Obese people in their 70s were neither at a heightened or lowered risk, while those in their 80s were 22 per cent less likely to suffer the disease, according to the findings published in Postgraduate Medical Journal.
Researchers analysed hospital records in England from 1999 to 2011 to see if a patient was diagnosed with obesity and if they later needed care or died from dementia.
During the study period, 451,232 of those admitted to hospital were diagnosed with obesity.
At least 820,000 people in Britain now suffer from dementia but by 2050 experts believe there will be 1.94 million, of which 650,000 cases could be prevented.
The researchers said one explanation for the high risk found in early to mid-life may be because obesity is associated with diabetes and cardiovascular problems, which are linked to dementia.
They said if people can stave off significant weight gain until at least their sixties they may have a lower risk of developing the condition.
The authors, led by Professor Michael Goldacre, concluded: “While obesity at a younger age is associated with an increased risk of future dementia, obesity in people who have lived to about 60-80 years of age seems to be associated with a reduced risk.”
There is no single way to prevent dementia but experts agree that people can take steps to reduce the danger of developing the condition by improving their lifestyle.
Dr Eric Karran, at Alzheimer’s Research UK, said: “There is an increasing body of evidence that lifestyle factors are linked to dementia risk.”