By Dean L. Winslow, MD, FACP, FIDSA

Professor of Medicine, Division of General Medical Disciplines, Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine

Dr. Winslow reports no financial relationships relevant to this field of study.

SYNOPSIS: Low levels of vitamin C were noted in seven of 11 patients with diabetes, including six of seven with lower extremity ulcers. Vitamin C repletion appeared to help heal these ulcers.

SOURCE: Christie-David DJ, Gunton JE. Vitamin C deficiency and diabetes mellitus — easily missed? Diabet Med 2016 Nov 18. [Epub ahead of print].

In this retrospective study, 11 patients with diabetes from a clinic in Sydney, Australia, with either nonhealing foot ulcers or who were suspected by history to have a poor diet were studied. Seven patients had nonhealing ulcers of their lower extremities, and four other patients without ulcers were suspected of having vitamin deficiency. In the group of 11 patients tested, the median vitamin C level was 19 umol/L (normal > 40 umol/L). Six of seven patients with lower extremity ulcers had low vitamin C levels compared to only one of four who did not have an ulcer and had low levels. All of these patients were treated with vitamin C 500-1,000 mg daily. Five of six patients with ulcers who were vitamin C-deficient healed their ulcers, and the remaining ulcer patient who was found to be zinc-deficient (but not vitamin C-deficient) healed after zinc repletion.

COMMENTARY

While this is a very small, non-randomized, observational study, I found the results intriguing. We all learned in medical school how important vitamin C is for wound healing and maintaining tissue integrity, but most of us practicing in the developed world probably do not even think of some of the subtler manifestations of scurvy. Although this small study does not describe well the presence or absence of traditional risk factors for lower extremity ulcers in these 11 patients with diabetes (vascular disease and neuropathy), the prevalence of vitamin C deficiency in this small cohort of patients is striking. I confess to not even considering vitamin C (or other micronutrient) deficiency in most of the generally obese diabetic patients I see in the hospital and clinic for diabetic ulcers and foot infections, but I will definitely do so in the future. Clearly a larger prospective, randomized study of assessment and repletion of vitamin C (and other micronutrients) in diabetic patients with foot ulcers would be welcome.