Obesity is responsible for nearly three times as many deaths among middle-aged and older Americans than previously thought, according to a new study from Columbia University.
Researchers found that obesity accounted for nearly 20 percent of deaths among white and black Americans between the ages of 40 and 85. Previously, many scientists estimated that about 5 percent of deaths could be attributed to obesity.
"Obesity has dramatically worse health consequences than some recent reports have led us to believe," said co-author Ryan Masters in a released statement. "We expect that obesity will be responsible for an increasing share of deaths in the United States and perhaps even lead to declines in U.S. life expectancy."
Obesity can lead to negative health consequences such as heart disease, stroke and diabetes. The Centers for Disease Control and Prevention estimate that more than one-third of American adults (35.7 percent) are obese.
Previous studies did not differentiate between age, sex and race when analyzing Americans' risk for obesity. In their study, published online in the American Journal of Public Health, researchers focused on mortality records from 1986 to 2006 for adults between the ages of 40 and 85, in order to rule out accidental deaths, homicides and congenital problems that cause more deaths among younger people. The study also built on previous research that found a person's risk for death from obesity increases with age.
Overall, black women had the highest risk of dying from obesity, at 27 percent, followed by white women at 21 percent. Additionally, obesity is nearly twice as common among black women as it is among white women.
Black men had the lowest risk of dying from obesity, at 5 percent. The researchers found that although black and white men had similar rates of obesity, black men's risk was likely lower because it is "crowded out" by other death causes, such as high rates of cigarette smoking and socioeconomic factors.
Although the effect of obesity on mortality rates among older Americans is already clear, combating the epidemic may be more challenging for younger generations, researchers said.
And while there have been reports that obesity rates are declining for certain groups, obesity-related deaths may continue to climb, as it is a difficult condition to reverse, the study said.
"A 5-year-old growing up today is living in an environment where obesity is much more the norm than was the case for a 5-year-old a generation ago," said co-author Bruce Link in a released statement. "And once someone is obese, it is very difficult to undo. So it stands to reason that we won't see the worst of the epidemic until the current generation of children grows old."