EXPERIMENT 2: Healthier by Pre-Commitment

Much of the time, we intend to make healthy choices but have trouble acting on these intentions. One arena where this phenomenon appears is in the grocery store. We set out to the store with every intention to return home with bags of fresh produce and whole grain items, but find ourselves in the checkout line with loads of unhealthy snacks and goodies.


We worked with Discovery Vitality in South Africa, an insurance plan that encourages its members to engage in healthy behavior (such as exercise, preventive care, and nutritious food choices), to create a voluntary pre-commitment program where Discovery Vitality members could put their 25% discount on groceries on the line by agreeing to increase their purchases of healthy food by 5 percentage points above their household baseline for each of 6 months. Members who did not sign up for this pre-commitment program would receive their discount as usual, but those who signed up added a voluntary hurdle in order to increase their healthy selections.


We found that 36% of members who were given this option agreed to participate, and these members maintained a 3.5% increase, on average, in healthy grocery items purchased in each of the 6 months. These findings suggest that a portion of consumers seize the opportunity to create restrictive choice environments for themselves in order to purchase healthier items, even at some risk of financial loss.

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