The federal government greatly overestimated deaths from obesity in the United States, according to new CDC estimates, which now ranks it as the No. 7 most-preventable cause of death, rather than No. 2.
As recently as January, the federal Centers for Disease Control and Prevention estimated obesity as being responsible for 365,000 deaths per year in the United States. But the new estimate, published today in the Journal of the American Medical Association (JAMA), puts the annual death toll at only 25,814 — the earlier estimate was about 14 times greater.
The CDC announcement comes as the U.S. Department of Agriculture, in its effort to stem rising obesity rates, yesterday introduced an updated and more tailored version of the food guide pyramid to help Americans live healthier.
Trial lawyers have latched onto rising obesity rates to push for class-action lawsuits against the fast-food industry, saying the industry should share some of the blame for America’s girth and calling fast food the new tobacco.
But George Washington University law professor John Banzhaf III, who has led the effort in supporting obesity-related litigation, said the new death statistic is irrelevant and would not affect obesity litigation.
“Any time a study comes from an organization, which is basically beholden to industry studying the case, one is suspicious,” he said.
The study, led by Katherine M. Flegal of the National Center for Health Statistics, a branch of the CDC, analyzed mortality according a person’s to BMI, or body mass index, which measures weight and height. It determined that being modestly overweight, but not obese, “was not associated with excess mortality” or a shorter life expectancy. In fact, the research shows that being overweight is actually less of a mortality risk factor than being of normal weight.
“The major reason our numbers are lower is that we used some new data sets that provide more recent, better information,” said David Williamson, senior epidemiologist for the CDC, who was an investigator in the study.
CDC Director Dr. Julie Gerberding said the CDC doesn’t plan to use the much-lower obesity mortality figure in its public-awareness campaign, nor does it plan to reduce its fight against obesity.
But this is the second time in nine months that the CDC has experienced trouble with its obesity death data. In July, it said obesity causes 400,000 deaths yearly, but scientists questioned the figure.
In January, the CDC admitted making calculation errors and lowered its death estimate to 365,000. Dr. Gerberding said yesterday the CDC will strive to improve its methods for calculating the health consequences of obesity.
Currently, obesity follows smoking as the second leading cause of preventable death. But the new estimate of less than 26,000, offered today, would rank it seventh behind such killers as vehicular crashes and gunshot wounds.
At this time, a BMI of less than 18.5 percent is defined as underweight. From 18.5 percent to 24.9 percent is considered normal, while a BMI of 30 percent or greater is considered obese.
But Mary Grace Kovar, a biostatician for the University of Chicago’s National Opinion Research Center, said “normal” may be set too low for today’s population. She said Americans classified as overweight are eating healthier foods, exercising more and controlling their blood pressure better.
“The findings are consistent,” Mr. Williamson said.
The Flegal study was one of two in this week’s JAMA that concluded the impact of obesity on cardiovascular disease risk or overall mortality has decreased over time.
Edward W. Gregg, another CDC epidemiologist, authored a second study that examined trends in heart disease over a 40-year period.
“Certainly, obese people today have a lower risk for CVD [cardiovascular disease] than those in previous decades,” he said.
“Our findings tell people that if they pay attention to other risks for cardiovascular disease and do good things,” such as quitting smoking and lowering cholesterol and blood pressure, “they can have an impact, whether or not they are obese,” Mr. Gregg added.
Marguerite Higgins contributed to this report