Socioeconomic differences associated with consumption of a plant-based diet: Results from the national health and nutrition examination survey

Background A plant-based diet (PBD) has been associated with potential health benefits, but factors that may affect access to and consumption of a PBD are not well defined. Aim To determine the association between socioeconomic status and plant-based dietary consumption among participants enrolled in the National Health and Nutrition Examination Survey (NHANES). Methods This was a cross-sectional study using data obtained from the NHANES database. The following covariates were assessed: age, sex, race/ethnicity, educational level, marital status, smoking status, physical activity, alcohol use, history of diabetes, and hypertension. Socioeconomic status was categorized according to poverty-income ratio (PIR). Food frequency questionnaires were used to calculate previously validated plant-based diet index (PDI) and healthful plant-based diet index (hPDI). Multivariable-adjusted logistic regression was performed to determine the association between PIR, clinical, demographic, and plant-based diet indices. Results A total of 5037 participants were in the final analytic sample. Median age of participants was 51 +/- 18.5 years. Overall PDI and hPDI were 50 [46-54] and 52 [47-57], respectively. Median PDI index was significantly different among PIR groups (PDI, p = 0.018; hPDI, p < 0.001). On multivariable analysis, participants in the poorest socioeconomic group (PIR <= 130%) were more likely to have lower consumption of a healthful PBD (hPDI). Conclusion Lower socioeconomic status (PIR <= 130%) was associated with decreased consumption of a healthful plant-based diet. These data suggest that socioeconomic disparities may limit consumption of healthier food and contribute to the high prevalence of adverse health conditions that exist in certain population groups.