Subjects: Behavioral health
Extreme obesity, defined as a Body Mass Index of 40 or higher, which for most people means being about a hundred pounds overweight, cuts life expectancy by 10 years, according to Richard Peto and colleagues at Oxford University in England.
That deleterious impact is the equivalent of a lifelong cigarette smoking habit.
The merely obese, who have a BMI in the range of 30-35, are sacrificing 2-4 years, while overweight folks, who have BMIs in the 25-29.9 range, short themselves and their loved ones by a year or so.
(If you know your height and weight, you can calculate your BMI here.)
The relationship between excessive weight and premature mortality turns out to be linear; for every 5-point jump in BMI above the optimal range, the risk of early death jumps by 30%.
The scientists reached these conclusions after pooling data from 57 studies of nearly 900,000 US and Western European adults that had been followed for 10-15 years.
Nearly 70,000 people died during the observation period. The scientists adjusted the data for age, smoking status and gender.
Almost all excess mortality was caused by cardiovascular disease and stroke, study co-author Gary Whitlock told USA Today. The epidemiologist explained that “obesity causes heart disease and stroke by pushing up blood pressure, mucking up blood cholesterol and triggering diabetes.”
The write-up appears in Lancet.
This is a “valuable study that provides a much clearer picture of the risk associated with various levels of being overweight or obese,” Michael Thun, an emeritus vice president of epidemiological research at the American Cancer Society told USA Today.
Nearly two-thirds of US adults are either overweight or obese, and fully half of those are obese.
“Once you gain weight, it’s hard to lose it and easy to gain more. So the goal to stop your weight gain now,” Thun warned.