The association between meat consumption and body mass index varies according to the socioeconomic status in a representative sample of French adults

There is a growing advocacy for reducing meat consumption in Western countries. However, healthier alternatives to meat may be more expensive, and populations with a low socioeconomic status (SES) may be more likely to replace meat by less healthy alternatives, which could reduce dietary quality and have negative effects on health outcomes such as weight gain. In the present study, we focused on the association between the body mass index (BMI), meat consumption and SES. We also studied the effect of interactions between meat consumption and SES on the consumption of food groups other than meat. We performed multivariate linear regressions based on a representative sample of the French adult population (n=1,300) collected in 2015. We found that among low-income households, one day less of meat consumption per month tended to be associated with a higher individual BMI (0.074±0.039 kg/m²) in significant contrast with the inverse association found in richer households (combining medium- and high-income groups). This income-based difference in the meat-BMI relationship was particularly strong in male, younger (aged 18-44) and rural adults. This result is robust to alternative SES indicators: other income classifications, levels of completed education, and the occupation classification. Low-income and higher-income households also had different eating habits associated with higher meat consumption: among low-income households, lower meat consumption was associated with higher consumption of ice cream and sorbet, while among higher income groups (>1 751 €/month), lower meat consumption was associated with lower consumption of high-fat and high-sugar food and beverage items, as well as cheese. Our study is the first to show that SES moderates the relationship between the level of meat consumption and BMI in a nationally representative sample. To understand whether promoting reduction in meat consumption could widenhealth inequalities, future works need to study the long-term effects of dietary changes on health as a function of SES.