We reviewed the literature to evaluate potential associations between vitamins, nutrients, nutritional status or nutritional interventions and the presence or healing of foot ulceration in diabetes. Embase, Medline, PubMed, and the Cochrane Library were searched for studies published prior to September 2020. We assessed eligible studies for the association between nutritional status or interventions and foot ulcers. Fifteen studies met the inclusion criteria and were included in this review.
Six of the articles, by the same team of investigators, raised concerns due to the close similarities between recruited patients and highly similar outcomes across the set of studies. We are unsure whether this data is reliable. Of the other studies, 3 assessed vitamin D. In all three, vitamin D deficiency was common in participants with diabetic foot ulcers. One study reported 85% deficiency rates, another 97.1% and the last 55.7%. Vitamin A, B12, C and E and zinc deficiency are also more prevalent in foot ulcer patients.
Overall, there is a correlation between poor nutritional status and the presence of foot ulceration or a delay in healing. Because of heterogeneity, the studies were not suitable for meta-analysis. There is not enough data to reach conclusions about whether the relationships are causal. However, where a deficiency is identified for any vitamin or nutrient, it should be treated with dietetic and/or medical supervision. Randomised controlled trials are needed to investigate whether specific nutritional supplementation improves foot ulcer healing and reduces rates of lower limb amputation.