Effectiveness of Sales Promotions on Vegetable Consumption Among Heterogeneous Consumer Groups: A Causal Forest Approach

A balanced diet with sufficient vegetable intake is vital for health, yet many in the US fall short of recommended levels. While the literature has extensively examined the effects of sales promotions, there is limited research addressing consumer heterogeneity in response to such promotions. We apply a machine learning approach that can uncover heterogeneity in promotional effects that conventional subgroup or regression‐based analyses are likely to miss. We find that in‐store price reductions boost vegetable consumption broadly. Households headed by young women with less formal education, larger households, low to mid‐level income households, and those that purchase vegetables less frequently are most responsive to price promotions. Conversely, middle‐aged and older, predominantly White households, households with more formal education, and higher incomes are less responsive. These findings suggest that targeted price promotions could be an effective tool to reduce health disparities by increasing vegetable consumption among populations most at nutritional risk.