A new study says that being obese can add years to your life and in some cases can be as dangerous as smoking. British researchers from the University of Oxford analyzed 57 studies, mostly in Europe and North America, following nearly one million people for an average of 10 to 15 years. During that time, about 100,000 of them died.
The studies used body mass index (BMI), a measurement that divides a person’s weight in kilograms by their height in meters, to determine obesity. The researchers found that the death rate was lowest among those whose BMI was between 23 and 24, on the high side of the normal range.
Health authorities generally define overweight people as those with a BMI of 25 to 29, and obese people as those with a BMI above 30.
The study was published online Wednesday in the medical journal The Lancet. It was paid for by the UK’s Medical Research Council, British Heart Foundation, Cancer Research UK and others.
“If you are trending towards obesity, it may be a good idea to lose weight,” said Sir Richard Peto, the study’s chief statistician and professor at the University of Oxford.
Peto and colleagues found that people who were moderately obese, with a BMI between 30 and 35, lost about three years of life. People who were morbidly obese – those with a BMI above 40 – lost about 10 years from their expected lifespan, similar to the effect of lifetime smoking.
Epidemiologist Gary Whitlock of the University of Oxford, who led the study, said moderately obese people were 50 percent more likely to die prematurely than people of normal weight.
Obese people are two-thirds more likely to die from a heart attack or stroke, and four times more likely to die from diabetes, kidney or liver problems, they said. They were one-sixth more likely to die of cancer.
“It really emphasizes the importance of gaining weight,” says Dr. said Arne Astrup, who was not involved with the Lancet study. “Even a small increase in your BMI is enough to increase your risk for heart disease and cancer.”
Previous studies have found that mortality rates increase both above and below the normal BMI score, and that people who are moderately overweight live longer than those who are underweight or of normal weight.
Other experts said that because the papers used in the study mostly began between 1975 and 1985, their findings were not as relevant today.
Astrup worries that rising obesity rates could reverse the steep decline in heart disease seen in the West.
“Obesity is the new dark horse for public health officials,” he said. “People need to be aware of the risks they face when they gain weight.”
Source by Sarra Miri
