Weight Change, Initial Weight Status and Mortality among Middle- and Older-Aged Adults

Mikko Myrskylä, University of Pennsylvania
Virginia W. Chang, University of Pennsylvania

We study how the weight change-mortality relationship is influenced by initial body mass index (BMI) and the magnitude of weight change. Using the Health and Retirement Study we find that among 50-70 year old Americans, large and small weight losses (3.0-5.0 and 1.0-2.9 BMI units) are associated with excess mortality unless initial BMI is above 32. For example, hazard ratio (HR) for large loss for BMI of 30 is 1.61 (95% CI: 1.31-1.98). HR for small loss for BMI of 30 is 1.19 (95% CI: 1.06-1.28). Large weight gains were associated with excess mortality if initial BMI was above 35 (HR for large weight gain from BMI of 35 is 1.33, 95% CI: 1.00-1.77). Small weight gains were not associated with excess mortality for any initial BMI level. These results suggest that the potential benefits of a lower BMI may be offset by the negative effects associated with weight loss.