Though the fountain of youth remains elusive, research is helping to identify factors that promote good health in the later stages of life. One of the clearest factors is maintaining a healthy weight. Numerous studies have shown that overweight is associated with an increased risk of chronic diseases and premature death. The problem, however, is not simply one of excess pounds paired with mounting years. A recent study from HSPH shows that adiposity in midlife is also associated with reduced chances of maintaining optimal health in old age.
In the investigation, Qi Sun, a research associate in the lab of Francine Grodstein, an HSPH associate professor in Epidemiology and an HMS associate professor of medicine at Brigham and Women’s Hospital, explored the underlying factors that influence the health of women who live into old age. The work relied on data collected from the Nurses’ Health Study, a prospective cohort study involving 17,065 women who survived until at least age 70. Health was defined as having no history of 11 major chronic diseases as well as having no substantial cognitive, physical or mental limitations; only 9.9 percent of the participants studied met these criteria.
After adjusting for lifestyle and dietary variables, the main factor that stood out was that increased body mass index (BMI) at baseline was significantly associated with linearly reduced odds of healthy survival to 70 and beyond; the mean age at baseline in 1976 was 50 years old. Compared to lean women (BMI of 18.5 to 22.9), obese women (BMI of 30 or more) had 79 percent lower odds of healthy survival. Moreover, the lowest odds of survival were among women who were overweight (BMI of 25 or more) at age 18 and gained more than 10 kg relative to women who were lean and maintained a stable weight.
The study appears in the Sept. 29 online edition of The British Medical Journal.
Students may contact Qi Sun at qisun@hsph.harvard.edu for more information.
Conflict Disclosure: The authors declare no conflicts of interest
Funding Sources: The National Institutes of Health and a pilot and feasibility program sponsored by the Boston Obesity Nutrition Research Center; Qi Sun was supported by a postdoctoral fellowship from Unilever Corporate Research; the authors are solely responsible for the content of this work.
