Obesity, Inactivity Each Up Death Risk
Researchers Debunk Idea That Being Fit Makes Up for Being Overweight
Dec. 22, 2004 -- Active women live longer. Lean women live longer. Lean, active women live the longest.
That's the news from Harvard researchers Frank B. Hu, MD, and colleagues, who analyzed 24 years of data on 11,564 female nurses followed since 1976.
While their study included only women, the researchers say their findings likely apply to men, too. Those findings, as reported in the Dec. 23 issue of The New England Journal of Medicine, include:
- By being lean but inactive (less than three and a half hours of physical activity per week) your risk of death increases by 55%.
- Being obese, even if you're active, increases your risk of death by 91%.
- Being obese and inactive means a 2.4-fold increased risk of death.
"We estimate that excess weight ... and physical inactivity ... together could account for 31% of all premature deaths, 59% of deaths from cardiovascular disease, and 21% of deaths from cancer among nonsmoking women," Hu and colleagues write.
Because few of the women in the study were African-American or Hispanic, it's not clear whether the study findings apply to these populations.
The researchers suggest that their findings disprove the idea that being fit makes up for being overweight. Lack of physical activity and being overweight are each independent risks for early death. Together, they are a double whammy.
It's probably better to never have gained the excess weight. But the study showed that women who lost 8.5 or more pounds actually had a 55% higher risk of death from heart disease. That may be because the study did not differentiate between intentional weight loss from dieting and unintended weight loss due to illness, notes an accompanying editorial by David R. Jacobs Jr., PhD, of the University of Minnesota, and Mark A. Pereira, PhD, of the University of Oslo in Norway.
"There remains much to learn about the associations among physical activity, fitness, and fatness in regard to the risk of chronic disease," Jacobs and Pereira write.
Our modern lifestyle makes it easy to eat too much and exercise too little, they note.
"The real challenge we face," Jacobs and Pereira write, "is promotion of a healthy lifestyle, including ample physical activity, a prudent, balanced diet, moderate or no alcohol consumption, and the avoidance of drugs and tobacco."