The Optimal Weight at Middle and Old Age: The Trade-Off between Active and Inactive Life Expectancy

Mieke Reuser, Netherlands Interdisciplinary Demographic Institute (NIDI)
Luc Bonneux, Netherlands Interdisciplinary Demographic Institute (NIDI)
Frans Willekens, Netherlands Interdisciplinary Demographic Institute (NIDI)

The obesity epidemic is a global phenomenon. Evidence of the health consequences of high bodyweight is conflicting. Recent studies do not show that overweight and mild obesity increase mortality risks, but it does raise chances to disability. We use the US Health and Retirement Survey (HRS) to estimate the impact of BMI on limitations of activities of daily living expressed as life expectancy (LE) with or without disability at middle and old age and compare it to smoking and education. Results show that overweight and obesity are a minor cause of death, but a major cause of disability, especially for women. At age 55, obesity (BMI 30-34.9) increased LE with disability with 2.0 [0.6-3.4] years for men and 3.2 [1.6-4.8] years for women compared to normal weight (BMI 23-24.9). Low education decreased disability-free life, but did not change life expectancy with disability. Smokers lived shorter both with and without disability.