By Nanci Hellmich
Are those extra pounds you're lugging around killing you? A new study is relaunching the debate about just how many people's deaths may be because of their obesity.
About one in five (18%) of deaths among white and African-American people in the USA, ages 40 to 85, are associated with people being overweight or obese, the latest research suggests.
Yet several national health experts think that may be an overestimate because of the methodology used for the analysis. Calculations from scientists with the Centers for Disease Control and Prevention suggest that about 5% of deaths a year in the U.S. are because of obesity.
A third of Americans (36%) are obese, which is roughly 35 pounds over a healthy weight. Obesity puts people at an increased risk for type 2 diabetes, heart disease, cancer and other diseases. Pinpointing obesity-related deaths is an evolving science as researchers use different statistical models to come up with estimates.
"Obesity has much worse health consequences than people realize," says the study's lead author Ryan Masters, who conducted the research as a Robert Wood Johnson Foundation scholar at Columbia University's Mailman School of Public Health.
Masters says the percentage of deaths attributed to obesity in his study is higher than previous estimates because he accounted for serious health complications of obesity among older adults, as well as higher rates of obesity among younger generations of Americans.
Still, Katherine Flegal, a CDC scientist and the lead author of the government research on this subject, says, "In our analysis the results for older people were pretty consistent across many studies."
Applying new statistical models to data from a national interview survey, Masters and colleagues estimate that between 1986 and 2006, 27% of deaths among black women; 22% of deaths among white women; 5% of deaths among black men; and 16% of deaths among white men could be attributed to being overweight or obese.There were too few individuals from other ethnic groups to include them in the analysis, Masters says.The findings are being published in theAmerican Journal of Public Health.
Ken Thorpe, professor of health policy at Emory University, says that the researchers of the new study didn't take into account factors such as alcohol use, smoking and health insurance so obesity "is getting credit" for deaths caused by those factors too. "Previous estimates focused on obesity-related deaths attributable to nonsmokers or never-smokers."
Thorpe says he's doubtful of the statistic that 27% of black women's deaths are attributable to obesity and overweight, and he questions the finding that white men are three times more likely to die from being obese and overweight than black men.
"The relative death rates among black and white men don't make sense because black males have higher obesity rates," Thorpe says. "And obesity-related chronic conditions, such as heart disease, cancer, diabetes and stroke, account for a similar share of the overall cause of death among black and white males."
Masters believes that obesity had less of an impact on mortality among black men than white men because black men have higher rates of smoking, HIV and other factors that contribute to premature death before obesity-related causes can take their toll.
Roland Sturm, a senior economist with the RAND Corp., a non-profit research group, says that although obesity has an impact on mortality, he doesn't believe it's three times previous government estimates. He says that obesity's biggest toll may be on long-term health and raising health care costs.
Thorpe says the bottom line is you should try to maintain a healthy weight, do at least 150 minutes of moderate-intensity exercise a week and eat a nutritious diet rich in lean protein, green garden vegetables, nuts, seeds and fruits.