Fruit and Vegetable Vouchers With and Without an SSB Tax

We will test the hypothesis that a positive incentive for healthy foods (fresh fruits and vegetables, F&Vs) will be utilized as effectively in a community without a purchasing penalty for unhealthy foods (a sugar-sweetened beverage [SSB] tax) as in a community with a purchasing penalty for unhealthy foods (a SSB tax). Our experiment will test the empirically-driven hypothesis in a real-world setting through a noninferiority design: comparing the impact of F&V vouchers in two counties, one without (Los Angeles) and one with (San Francisco) a SSB tax.

Each study participant will receive four paper vouchers per month for a total of six months. Each of these vouchers can be redeemed for fresh or frozen fruits and vegetables at a number of specified local corner stores, supermarkets, or farmer's markets.

Half of these participants will receive and spend these vouchers in an environment which has implemented a SSB tax (SF); the other half will receive and spend these same vouchers in a non-tax environment (LA).

Each individual participant will be enrolled in the study for a total of seven months from initial orientation and participant consent (M0) to final data collection during final month of intervention (M6).

We are using a non-inferiority trial design. We are aiming to test whether there is a significant difference in total cup-equivalents of F&V intake in LA participants as compared to SF participants when given F&V vouchers. That is, we aim to test whether the F&V voucher is less effective in LA than in SF. This is important to test because it has been purported that SF has a unique food environment with high accessibility to fresh F&V through farmer's markets and a plethora of corner stores, as well as a SSB tax that discourages less healthy foods, potentially leaving more funds for healthier F&Vs. Thus, we aim to determine the change in consumption of F&V in LA participants is non-inferiority to that of SF participants, when both are given F&V vouchers.

Inclusion criteria

• Understand English sufficiently to provide informed consent;
• Provision of signed and dated informed consent form;
• Stated willingness to comply with all study procedures and availability for the duration of the study;
• Any gender, aged 21 years or older;
• Have self-reported income ≤250% of the federal poverty level;
• Have regular access to a mobile phone;
• Have a safe and secure mailing address at which to receive vouchers;
• Be a resident of the Counties of San Francisco or Los Angeles as defined by official municipal boundaries.

Exclusion criteria

• Currently participating in any other dietary or nutrition study that would impact his or her normal eating patterns;
• Currently be enrolled in and receiving EatSF, CHIVES, or Vouchers4Veggies vouchers;
• Has active diagnosis of cancer or congestive heart failure;
• Is planning to move out of San Francisco or Los Angeles in the next 12 months;
• Currently pregnant.
• Currently live with and share a food budget with a current Vouchers4Veggies, EVIDENCE, or CHIVES study participant.