Overweight Seniors Live Longer

Australian researchers report that seniors 70 and older may benefit from being overweight, but not obese.

From medieval alchemists’ “elixir of longevity” to the miraculous healing properties of goji berry granola, the crusade against aging has spawned countless complex hypotheses. For seniors seeking a longer life, a new Australian study may point to a simpler solution: gain a few extra pounds (but not too many).

The large-scale study, published in the Journal of the American Geriatrics Society, examined health factors for more than 9200 seniors, aged 70 to 75, between 1996 and 2006. The researchers’ primary aim was to determine the nature of the relationship between body mass index (BMI) and mortality risk in older people. The study used BMI categories defined by the World Health Organization.

Participants with a BMI of approximately 26—slightly overweight, by the book—showed the lowest risk of mortality. As BMI decreased, risk increased, to the extent that it doubled in women who were just shy of underweight.

The results contradicted public health messages, which advocate that patients keep their BMI in the relatively narrow “normal” range between 18.5 and 24.9. Researchers were careful to note that obesity was not found beneficial to longevity, however. Mortality increased with extreme obesity, revealing a U-shaped relationship between BMI and mortality.

The authors concuded that BMI thresholds for normal and overweight, which are based on evidence of obesity-related risk in younger and middle-aged people, may be too restrictive for older patients.