BMI categories across different living arrangements

Research on the prevalence of body mass index (BMI) categories across different living arrangements remains limited. We aimed to quantify the prevalence of BMI categories among those living alone (LA) and those not living alone (NLA).

In this population-based cross-sectional study, we used individual-level data from the 2011-2021 Behavioral Risk Factor Surveillance System. Main outcomes were prevalence of BMI categories in LA and NLA, adjusted for age, gender, and race/ethnicity, and socioeconomic status, using logistic regression and model-predicted marginal prevalence to estimate BMI categories prevalence.

Between 2011 and 2021, we quantified BMI categories prevalence in 4,195,414 adults in the BRFSS, with 1,197,787 (28.5%) adults LA and 2,997,627 (71.5%) adults NLA. In comparison to NLA, LA consistently demonstrates lower adjusted obesity prevalence across genders and age groups, with the highest prevalence observed in the 45-64 age range, particularly within the 45-54 group (LA: 37.4%, 95% CI: 37.1-37.8%; NLA: 34.3%, 95% CI: 33.8-34.7%). Additionally, LA displays an overall lower adjusted prevalence of overweight compared to NLA, notably in the 18-34 and >64 age groups.

Heterogeneity in BMI categories prevalence exists between LA and NLA. Future studies and public health efforts should consider this heterogeneity.