Fitness & Exercise

Fit Beats Fat for a Longer Life

Exercise Linked to Longer Survival continued...

Newman tells WebMD that while fitness appears to be a more important predictor of survival in older people than weight, many unanswered questions remain, such as why obesity appears less dangerous in this age group than in younger people.

"It may be that that the diseases associated with obesity, such as diabetes, arthritis, and heart disease, are already evident by late middle age," she says.

Because it was also not clear how long the obese people in the study had been overweight, she adds that their improved survival may not reflect the dangers of a lifetime of obesity.

"People definitely don't need an excuse to gain weight," she tells WebMD. "But we have found that heavier older people do not appear to be as sick."

Blair says public health messages aimed at keeping older people healthy should focus more on physical activity and less on weight loss.

Walking or engaging in similar exercise 30 minutes a day, five days a week is enough for older people to achieve moderate physical fitness, he says.

"The message these days is that obesity is the worst public health crisis we've ever faced," he says. "If physical activity gets mentioned, it is usually thrown in as an afterthought. But our research over the last dozen years, including this study, shows that physical activity and fitness play a big role in health."