VITAFOOT: A Double-Blind, Randomized Controlled Pilot Trial of Combined Vitamin C, Vitamin A, and Zinc Supplementation in People With Nonhealing Diabetes-Related Foot Ulcers

OBJECTIVE Micronutrient deficiencies are common in patients with diabetes-related foot ulcers (DFUs); however, effects of micronutrient supplementation on DFU healing are unclear. We evaluated the effect of combined vitamin C (VitC), vitamin A (VitA), and zinc supplementation on wound healing in patients with nonhealing DFUs. RESEARCH DESIGN AND METHODS Participants in the VITAFOOT study, a double-blind, randomized controlled pilot trial, were assigned to receive 28 days of combination supplement containing VitC (1,000 mg), VitA (750 μg/2,500 IU), and zinc picolinate (25 mg) daily or identical placebo. The primary outcome was percentage change in DFU area from baseline to 12 weeks. Post hoc exploratory outcomes included complete healing at 4 and 12 weeks. RESULTS Ninety-nine participants were randomized to either the placebo (n = 50) or the intervention (n = 49) group. Baseline deficiencies in VitC, VitA, and zinc were observed in 49 (49.5%), 1 (1%), and 11 (11.1%) participants, respectively. At 12 weeks, there was a median (interquartile range) 65% (10–100%) reduction in DFU area in the intervention group and 75% (43–100%) reduction in DFU area in the placebo group (P = 0.42). At 4 weeks, 7 of 49 DFUs (14.3%) healed in the intervention group compared with 1 of 50 (2%) in the placebo group (P = 0.02). At 12 weeks, 13 of 49 wounds (26.5%) were healed in the intervention group, as were 14 of 50 (28%) in the placebo group (P = 0.87). CONCLUSIONS Despite high baseline rates of VitC deficiency, micronutrient supplementation for 28 days did not improve percentage change in DFU area at 12 weeks. A higher proportion of patients had complete DFU healing at 4 weeks in the intervention group, but there was no difference at 12 weeks compared with standard care.