Socioeconomic status as a risk factor for unhealthy meat substitutions in a context of reducing meat in diet – SubMeat

Today, lowering meat consumption for health and environmental reasons meets a growing advocacy in Western countries, and could be supported by economic measures in the coming years. However, in practice, substituting meat in the diet could lead to consumption patterns with different nutritional outcomes, and socioeconomic status (SES) may be a determinant of these patterns. Populations with a low SES might be more likely to replace meat by foods that are less healthy, but cheaper and more accessible to them, which could result in lower dietary quality and negative health outcomes such as weight gain. Everything being equal, existing dietary and health inequalities between the rich and the poor would therefore become even more pronounced. However, so far, the role of SES as a potential mediator in the meat consumption-body mass index (BMI) relationship has not been investigated. Our pilot study on nationally representative cross-sectional data showed a striking contrast in the association between meat consumption and BMI comparing low- and high-SES French adults: we found that a lower frequency of meat consumption is associated with a lower individual BMI among high-income households, but a higher individual BMI among low-income households. The current project aims at going further to explore the longitudinal dynamics of the relationship between SES, meat reduction and risk of weight gain, and inferring causal links. We will study if risky weight gain could be explained by SES-based differences in food consumption patterns in a context of meat intake reduction. We will also investigate main motivations and difficulties to meat reduction encountered by low-SES compared to high-SES individuals. Our consortium brings together scientific experts in the fields of applied economics, nutrition epidemiology, physiology of protein intakes and food behavior, as well as specialists in design of nutrition interventions and information campaigns for general public. Thanks to this combination of expertise, we will implement a research strategy divided in three work packages: (1) We will study longitudinal household food purchase data using econometric and epidemiological approaches to identify patterns of meat consumption according to various SES indicators (income, education, and occupation) and their relationship to weight change along time in a context of meat intake reduction. We will also investigate transmission pathways to observe potential unhealthy food consumption patterns that arise when meat consumption decreases among the poor compared to the rich. (2) Original mixed-methods studies of food behavior in the context of meat reduction will allow us to confirm the transmission pathways in real-life observations, measure physiological parameters to estimate health outcomes of meat reduction among the poor compared to the rich, and identify SES-dependent motivations, levers and difficulties of meat reduction. We will conduct a short-term study on a community sample that will be complemented by a one-year survey in students within university restaurants. (3) Food choice experiments and an action research intervention will be implemented to orient consumer choices towards better plant-based options. Overall, our research will help closing the knowledge gap in the importance of the SES as a factor of transition towards more sustainable diets. This multi-disciplinary project will have a direct societal impact by offering data to inform policy makers and tools to help low-SES populations to find a better balance between animal and plant sources in the diet while reducing risks of negative outcomes. This project will lay out the path towards sustainable and healthy diets for all.