LONDON (Reuters) - If the threat of diabetes, heart disease and stroke weren't enough incentive for obese people to lose weight, scientists have discovered another -- dementia.
Researchers in the United States have shown that obesity, particularly in women, increases the risk developing dementia later in life.
"Obesity in middle age increases the risk of future dementia," said Dr Rachel Whitmer, of Kaiser Permanente, a health care organization in Oakland, California.
She and her colleagues studied more than 10,000 men and women who were given detailed health evaluations from 1964 to 1973 when they were 40-45 years old. After a 27-year follow-up, seven percent of the patients had developed dementia.
"People who were obese in mid-life were 74 percent more likely to have dementia, while overweight people were 35 percent more likely to have dementia compared to those with normal weight," said Whitmer, whose findings were reported online by the British Medical Journal on Friday.
The highest risk was for obese women who had a 200 percent greater risk of dementia than females of normal weight.
Obesity is measured by body mass index (BMI), calculated by dividing weight in kilograms by height in meters squared. A BMI of 30 or more is considered obese.
Excess weight is also linked to higher risk of heart disease, diabetes, certain cancers and psychological problems.
Whitmer and her team said that if their findings are confirmed, treating obesity in middle age could help to reduce the risk of dementia in later life.
Because of the aging of the global population, dementia is expected to increase 400 percent in the next 20 years. Some estimates predict there will be 45 million sufferers worldwide by 2050.
"Failure to contain the present epidemic of obesity may accentuate the expected age-related increase in dementia," Whitmer added.
© Reuters 2005. All Rights Reserved.