A few extra pounds help the elderly

Prior to reaching the golden years, too much body fat tends to increase the risk of dying, but extra weight may have the opposite effect for older adults. Higher fat mass in older adults is thought to be an energy reserve that helps the individual survive illnesses and chronic conditions.

Researchers used data from the Third National Health and Nutrition Examination Survey conducted between 1988 and 1994 to assess body mass, waist circumference, waist-to-hip ratio, hip circumference, and other body mass and body fat indicators among 4,437 men and 5,166 women in Canada. Overall, 1,116 of them were 65 to 75 years old and 1,200 were older than 75 years. Over an average of 8.7 years, 1,466 study participants died.

In the study, many lower weight and body fat indicators were associated with a greater risk of dying among men and women aged 65 and older. Among individuals older than 75, having a low versus a normal body weight seemed to raise the risk of death from any cause by a factor of 1.6 in men and nearly 3 in women.

As expected, the fewest deaths - 4 percent in men and 3.5 percent in women - occurred among those 18 to 64 years old. In this group, the risk of death was increased in obese men and in overweight and obese women. But in the older groups, being underweight was associated with greater mortality, whereas being overweight was associated with lower mortality.

When considering risk of death, obesity may be a greater concern in younger than older adults. Weight management should continue to be a target for reductions in illness and death in younger individuals. However, in light of the findings, although weight loss may improve risk for various co-existing illnesses associated with obesity, the appropriateness of weight loss as an intervention to extend longevity in older populations is unclear and warrants further investigation.