Impacts of incentivizing milk spending among SNAP participants

Incentive programs to encourage healthier eating among US households generally focus on fruits and vegetables, and little is known about incentivizing other components of a healthy diet. The Healthy Fluid Milk Incentive (HFMI) funds projects that provide discounts for households participating in the Supplemental Nutrition Assistance Program (SNAP) when they purchase lower-fat milk products.

We used transaction data from a large retailer participating in an HFMI project (Add Milk) to estimate the impact of HFMI discounts on sales of different types of milk. We measured monthly spending among households that consistently purchased milk at the retailer. We used difference-in-differences and event study models to estimate the impact of Add Milk on SNAP households compared with non-SNAP households.

We found that Add Milk discounts increased spending on 1% milk among SNAP households by up to 21.0% and did not impact fat-free milk spending. The program took over 6 months to see an impact. Sales of higher-fat milk were reduced and sales of flavored milk were not affected.

These findings demonstrate the feasibility of incentivizing dietary components beyond fruits and vegetables but the difficulty of inducing substitution away from less-healthy items.