Nativity differences in the body roundness index, with reference to body mass index, among Black adults in the United States: NHANES 2011–2018

Studies frequently view Black populations as homogenous, disregarding important diversity within this population. Furthermore, nativity can be key to distinguishing health risks among this population. Yet few researchers have examined these distinctions using body roundness index (BRI), a measure of central adiposity. We assessed the relationship between nativity and BRI among non-Hispanic Black people in the United States (US) using cross-sectional data from the 2011-2018 National Health and Nutrition Examination Survey (NHANES). BRI was calculated using height, weight, and waist circumference. Nativity was categorized as US-born and foreign-born. Multilinear regression analysis was used to evaluate the relationship between BRI and nativity, controlling for demographic characteristics and Healthy Eating Index scores. The average age and BRI score of participants were 44.74 ± 0.46 and 5.36 ± 0.04, respectively. Among eligible participants (3341), 9.6% were foreign-born (n = 322). In multivariate regression models adjusting for covariates, men had significantly lower BRI scores than women (4.67 ± 0.04 versus 5.96 ± 0.05; β = -1.25; t₆₁ = 24.60; P < 0.0001), and BRI increased with age (β = 0.02; t₆₁ = 9.17; P < 0.0001). US-born Black people had significantly higher BRI scores compared to their foreign-born counterparts (5.40 ± 0.04 versus 5.00 ± 0.09; β = -0.36; t₆₁ = -3.99; P = 0.0002). Results suggest that nativity is associated with central adiposity, with potential implications for cardiometabolic disease risk.