Household income and obesity among older adults: the moderating role of race in a longitudinal analysis

Background
Obesity among older adults in the United States is a growing public health concern, with rising rates contributing to chronic disease, disability, and premature mortality. While higher income is generally associated with lower obesity risk, this relationship may not hold equally across racial and ethnic groups. This study examines how household income relates to obesity among older adults and whether race moderates this association.

Methods
We used longitudinal data from the Health and Retirement Study (2014–2018), a nationally representative panel of U.S. adults aged 50 and older (N = 12,118). Obesity was defined as BMI ≥ 30 using self-reported height and weight. Household income was measured both continuously and in quartiles. We estimated mixed-effects logistic regression models with race-income interaction terms, adjusting for age, gender, nativity, work status, functional limitations, and survey year.

Results
Higher income was associated with reduced odds of obesity overall (OR = 0.95 per $10,000, 95% CI: 0.92–0.99), but this protective effect differed by race. Among White older adults, income was strongly protective; among Black adults, income had no significant effect (interaction OR = 1.05, p < 0.05); and among Hispanic adults, the effect was weaker and non-significant. Obesity disparities persisted across income levels, with high-income Black seniors having higher obesity prevalence than low-income Whites.

Conclusions
Income-based health advantages do not accrue equally across racial groups. Interventions must go beyond economic measures to address structural barriers, cultural contexts, and life-course disadvantage that shape obesity risk in later life.