Case Study

Healthier Food Purchases by Pre-Commitment


People often have difficulty engaging in healthy behaviors on their own and look to programs for help. How should these programs be designed to ensure that members get the most out of them?


We were interested in how we could use pre-commitment incentives to encourage people to make healthier food purchases. We worked with Discovery Health (an insurance company based in South Africa) to maximize the power of incentives to change health behaviors in its Vitality rewards-based program. Participants were offered the opportunity to pre-commit to increasing their healthy food purchases at the grocery store by 5% each month or else lose their pre-existing healthy food cash-back bonus.


In total, 36% of eligible households chose to pre-commit to the program, increasing their healthy food purchases by 3.5% in each of the study’s six months.

Why it matters

Offering pre-commitment devices may be an effective tool to help people activate and maintain self-control when making food purchases.