Weighty Death Toll Downplayed
The death toll from being overweight or obese is far less than a controversial government estimate released last year that body fat killed about 400,000 people annually and was poised to outstrip tobacco as the leading preventable cause of death, according to a new study.
The study estimated that obesity killed about 112,000 people, most of whom were extremely obese with body sizes equivalent to a 5-foot-4-inch woman who weighed 204 or more pounds. The effects of milder obesity on death were less severe.
In addition, the scientists found that being underweight killed an estimated 34,000 Americans each year. Risk of death from being underweight was especially high among the elderly.
The scientists reported that people who were merely overweight, as opposed to obese, suffered 86,000 fewer deaths than those whose weight was in the so-called healthy range.
"I think the punch line is obesity is associated with an important number of excess deaths but there has been a little too much hysteria before," said Roland Sturm, a senior economist at Rand Corp., a Santa Monica think tank. "Now we come to some probably more credible, reasonable numbers."
But some scientists said the new study had methodological problems that could underestimate the death toll from fat.
"I think the papers are really naive, deeply flawed and seriously misleading," said Dr. Walter Willett, chairman of the department of nutrition at the Harvard School of Public Health. "This is a huge problem, it's getting worse fast and there's no turnaround in sight."
The paper, published today in the Journal of the American Medical Assn., was written by Katherine Flegal and David Williamson of the Centers for Disease Control and Prevention, and Barry Graubard and Mitchell Gail of the National Cancer Institute.
The team used three national population surveys to calculate the risk of death associated with weight, which was measured using the body mass index, or BMI. The index estimates plumpness based on someone's height and weight. A BMI of 18.5 to 24.9 is considered healthy; 25 to 29.9 overweight; and 30 and above, obese.
The scientists then used a more recent national sample collected between 1999 and 2002 to calculate the total number of people who fell into different BMI categories.
Putting the two together, they could estimate how many people died each year because of their weight.
