This will surprise most of us. An Australian study published in the Journal of the American Geriatrics Society finds that adults over 70 who are overweight but not obese are less likely to die in a 10-year period than those with “normal” weight.
This may lead to new guidelines on Body Mass Index (BMI) for older people.
Here’s the story from Science Daily:
The study began in 1996 and recruited 4,677 men and 4,563 women. The participants were followed for ten years or until their death, whichever was sooner, and factors such as lifestyle, demographics, and health were measured. The research uncovered that mortality risk was lowest for participants with a BMI classified as overweight, with the risk of death reduced by 13% compared with normal weight participants. The benefits were only seen in the overweight category not in those people who are obese.
“Concerns have been raised about encouraging apparently overweight older people to lose weight and as such the objective of our study was to examine the major unresolved question of, ‘what level of BMI is associated with the lowest mortality risk in older people?’” said lead researcher Prof. Leon Flicker, of the University of Western Australia. “These results add evidence to the claims that the WHO BMI thresholds for overweight and obese are overly restrictive for older people. It may be timely to review the BMI classification for older adults.”
In those participants who died before the conclusion of the study, the researchers concluded that the type of disease which caused their death, for example heart disease or cancer, did not affect the level of protection being overweight had. To remove any risk of bias in participants with illnesses which caused them to lose weight, and also increased their risk of dying, the researchers contrasted subjects who were relatively healthy compared with those who had major chronic diseases or smoked and found no apparent differences in the BMI: mortality relationship.
While the same benefit in being overweight was true for men and women, being sedentary doubled the risk of death for women, whereas it only increased the risk by a quarter in men.
