Voucher for Healthy Foods and Diabetes Control: A Randomized Clinical Trial

Programs to improve access to healthy foods for people with diabetes exist in some jurisdictions but not others, and their effects on disease control are not established.

To measure the effect of a monthly grocery store voucher that allows access to healthy foods on diabetes control in patients experiencing food insecurity.

This randomized parallel-arm clinical trial was conducted from March 21, 2023, to April 1, 2025, at 7 sites in Toronto, Canada. Patients were randomly allocated to a monthly voucher or usual access to healthy foods. Eligibility required hemoglobin A1c (HbA1c) levels from 6.0% to 11% and food insecurity. Data analysis was conducted in May 2025.

A $65 monthly voucher ($85 for those in households with 6 or more individuals) for 6 months.

The primary outcome was change in HbA1c levels from baseline to 6 months. Secondary outcomes included levels of β-carotene and ascorbic acid, self-reported fruit and vegetable consumption, financial security, food security, and general health.

Of 1061 patients approached, 390 were enrolled (mean [SD] age, 60 [13] years; 191 [49%] men, 198 [51%] women); 81 (21%) identified as Black, 93 (24%) identified as South Asian, and 105 (27%) identified as White. Overall, 194 (50%) were randomly allocated to receive the voucher and 196 (50%) to control. The nonsignificant mean difference between voucher and control in the change in HbA1c was -0.18% (95% CI, -0.41 to 0.05; P = .13; mean difference adjusted for baseline HbA1c, age, sex, household size, and condition, -0.10%; 95% CI, -0.33 to 0.12; P = .35). The voucher improved self-reported vegetable consumption (44.7% vs 21.5% 2 or more times per day), fruit consumption (42.6% vs 22.7% 2 or more times per day), food insecurity (risk difference, -0.10; 95% CI, -0.18 to -0.02), and general health (odds ratio, 1.6; 95% CI, 1.1-2.3) but not financial insecurity (risk difference, -0.07; 95% CI, -0.16 to 0.02) or β-carotene level (mean difference, 0.01 µmol/L; 95% CI, -0.08 to 0.06) and ascorbic acid level (mean difference, -0.18 µmol/L; 95% CI, -4.3 to 4.7).

In this randomized clinical trial, a monthly food voucher did not have an effect on HbA1c control or objective measures of diet quality but the voucher did increase self-reported vegetable and fruit consumption.

ClinicalTrials.gov Identifier: NCT05776420.