Vitamin D’s Role in Viral Warts Unclear

Whether oral vitamin D supplementation in patients who are vitamin D deficient would result in wart clearance was investigated.

Vitamin D serum levels may be lower among patients with viral warts, but more robust studies of oral supplementation with vitamin D are needed before determining whether such therapy can play any role in wart clearance, according to study findings published in the Journal of Cosmetic Dermatology.

Researchers sought to measure vitamin D serum levels in patients with viral warts and those in healthy control group participants and to determine whether oral vitamin D supplementation in patients who are deficient in vitamin D would result in wart clearance.

The case control study included 80 participants in 2 groups (40 patients with viral warts and 40 healthy control participants) who presented to a dermatology outpatient clinic from July 2019 to August 2020. The patients with viral warts were categorized into 3 subgroups according to vitamin D status (14 patients with normal vitamin D levels, 16 with insufficient vitamin D levels, and 10 with deficient vitamin D levels).

Of the patients with warts (age range, 11-42 years, mean age, 30.20±9.19 years; 72.5% men and boys), 7 (17.5%) had a positive family history of viral warts. A total of 12 patients (30%) had common warts, 17 (42.5%) had plantar warts, 7 (17.5%) had flat warts, and 4 (10%) had filiform warts. Within this group, 14 patients (35%) had sufficient levels of vitamin D, 16 (40%) had insufficient levels, and 10 (25%) had deficient levels.

In the control group (age range, 14-47 years, mean age, 31.85±9.06 years; 75% men and boys), 12 individuals (30%) had sufficient vitamin D levels, 18 (45%) had insufficient levels, and 10 (25%) had deficient levels.

Sex was not significantly associated with vitamin D serum levels (P =.112), although vitamin D deficiency was significantly higher in women (P =.025). A family history of warts did not significantly affect vitamin D serum levels, nor did status within the case group (P =.550; P =.482, respectively). Patients with plantar warts had significantly decreased vitamin D serum levels (P =.044).

Of the patients with warts, 26 with insufficient and deficient vitamin D levels were treated with a weekly dose of oral vitamin D for 3 consecutive months until normalization and were then re-evaluated. Of this group, 13 had no wart response to vitamin D, 5 had a partial clearance, and 8 had complete regression of warts.

Duration and number of warts did not significantly correlate with serum levels of vitamin D (P =.832, P =.561, respectively). Serum levels of vitamin D did not affect warts’ response or the degree of response to treatment (P =.250, P =.101), it was noted.

No significant decrease was observed in the serum 25-OH vitamin D levels in patients with viral warts compared with control group participants (P =.908), despite lower levels occurring in patients with warts. An insignificant deficiency in vitamin D status was observed in patients and control group participants (P =.873).

The study was limited by its small sample size. Controlled studies on the genetic, molecular, and tissue aspects of vitamin D are warranted “before establishing a concrete solid role of vitamin D in immune regulation of wart treatment,” noted the investigators. The study was conducted during the summer, which may have led to a larger number of participants considered as having a sufficient level of vitamin D.

“Vitamin D3 is an inexpensive drug that has proven to be very beneficial especially in developing countries,” the study authors commented. “Its effect on immune regulation and boosting cutaneous immunity requires [validation] by further larger-sample, controlled clinical and genetic studies.”


Shalaby ME, Hasan MS, Elshorbagy MS, Abo Raya AR, Elsaie ML. Diagnostic and therapeutic implications of vitamin D deficiency in patients with warts: a case-controlled study. J Cosmet Dermatol. Published online April 15, 2021. doi:10.1111/jocd.14156