How being fat in your 30s could triple the risk of dementia

Being overweight in your 30s triples the risk of dementia in later life, warn researchers.

A new study shows that being fat in your ‘midlife’ years is likely to accelerate the loss of memory and other brain skills, The Daily Mail reports.

Oxford University researchers found the age at which a person is obese is a key factor – with the highest risk of developing dementia found in those who are very overweight in their 30s.

They say the risk of dementia may be raised or lowered depending on the age when weight gain runs out of control.

The increased risk of dementia fell the later in life obesity was diagnosed, according to the study of almost half a million people. Those who were obese past age 70 were no more likely to develop dementia than those who were not obese.

The researchers looked at English hospital records from 1999-2011, during which 451,232 of those admitted to hospital were diagnosed with obesity.

The small time span means that although only 19 people who were obese in their 30s in the study went on to develop dementia, they did so at a relatively young age – while still in their 40s or early 50s.

The rate was more than three times higher than would be expected by this age, when compared to the rates for other age groups. For those in their 40s, the equivalent extra risk fell to 70 per cent, for those in their 50s it dropped to 50 per cent, while those in their 60s had a 40 per cent extra risk, according to the study published online in the Postgraduate Medical Journal.

Obese people in their 70s were neither more or less at risk of developing dementia, while those in their 80s were 22 per cent less likely to develop the disease.

Experts do not know exactly why obesity impacts on the risk of dementia, although hardening of the arteries and high blood pressure play a role. Previous research has also shown that abdominal obesity has a particularly harmful effect on the brain, probably because it is ‘metabolically active’, releasing more of the acids that raise heart disease risk, along with factors that increase blood pressure and blood sugar.

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