Exercise Linked to Longer Survival
The study is not the first to find fitness among the elderly to be one of the best predictors of survival.
In research reported in 2006, Anne B. Newman, MD, MPH, and colleagues from the University of Pittsburgh found an inability to walk 400 meters, or about a quarter of a mile, to be associated with an increased risk of death in people between the ages of 70 and 79.
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.
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."