Obesity triples the risk of dementia, women warned
IAN JOHNSTON
SCIENCE CORRESPONDENT
MIDDLE-AGED women’s chances of getting dementia are increased by 200 per cent if they are obese, according to a study of thousands of people over three decades.
Scientists in California, who examined the health records of more than 10,000 people, warned failing to deal with the "epidemic of obesity" gripping the US - and gaining pace in the UK - would cause an increase in the numbers of elderly people suffering from Alzheimer’s disease in the future.
The study, reported in the British Medical Journal, found that people who were obese were 74 per cent more likely to get dementia, while those who were merely overweight were 35 per cent more likely.
But the link between weight and developing dementia was far more pronounced in women. Obese women were 200 per cent more likely to have dementia than women of normal weight, while obese men had a "non-significant" 30 per cent increase in risk.
Epidemiologist Dr Rachel Whitmer, of the Kaiser Permanente Division of Research in Oakland, said in a report: "Obesity and overweight in middle age - as measured by body mass and skin-fold thickness - were strongly associated with risk of dementia in later life.
"If these results can be confirmed elsewhere, perhaps treatment of obesity might reduce the risk of dementia.
"Failure to contain the present epidemic of obesity may accentuate the expected age- related increase in dementia."
The scientists found that 713 of the 10,276 people studied went on to develop dementia. They used detailed medical records of people aged 40 to 45 from 1964 to 1973 and compared these with records from the same people in 1994.
Obese people have a body mass index (BMI) of 30 or above, while overweight people’s BMI is classed between 25 and 29.9. A normal BMI is between 18.6 and 24.9. BMI can be calculated by dividing your weight in kilograms by the square of your height in metres.
Dr Whitmer said obesity could have a direct effect on brain-cell damage. Experiments have shown genetically obese rats perform badly on spatial memory tasks.
The report cautioned that there were fewer obese men than women in the study and also said the BMI might not be useful when comparing male and females as fat was dispersed differently through the body.
Professor Clive Ballard, research director of the Alzheimer’s Society, said the scientists had come up with a "striking observation".
"Given that the number of people with dementia is already increasing dramatically as our population ages, it will be important to minimise additional preventable risk factors such as obesity," he said.
"The findings also build on an accumulating body of evidence emphasising that a healthy lifestyle can help to reduce the risks of dementia."
From (thescotsman.scotsman.com)