Effects of Zinc Supplementation on Inflammatory Skin Diseases: A Systematic Review of the Clinical Evidence.

BACKGROUND: Zinc has been used in patients with acne vulgaris for its anti-inflammatory effects; however, it is unclear if zinc supplementation is also beneficial in other inflammatory skin conditions. OBJECTIVE: The objective of this article was to determine the effect of zinc supplementation on inflammatory dermatologic conditions. DATA SOURCES: We searched the Cochrane Central Register of Controlled Trials, EMBASE, MEDLINE, and Ovid with no time limit up to 29 May, 2019. Trials examining supplementation with zinc in the treatment of inflammatory dermatological conditions (acne vulgaris, atopic dermatitis, diaper dermatitis, hidradenitis suppurativa, psoriasis, and rosacea) in children and adults were selected. RESULTS: Of 229 articles, 22 met inclusion criteria. Supplementation with zinc was found to be beneficial in ten of 14 studies evaluating its effects on acne vulgaris, one of two studies on atopic dermatitis, one of one study on diaper dermatitis, and three of three studies evaluating its effects on hidradenitis suppurativa. However, the one article found on psoriasis and the one article found on rosacea showed no significant benefit of zinc treatment on disease outcome. CONCLUSIONS AND IMPLICATIONS: Some preliminary evidence supports the use of zinc in the treatment of acne vulgaris and hidradenitis suppurativa; however, more research is needed with similar methodologies and larger sample sizes in these diseases. Further, zinc may be of some benefit in the treatment plan for atopic dermatitis and diaper dermatitis; however, additional studies should be conducted to further evaluate these potentially positive associations. To date, no evidence is available to suggest that zinc may be of benefit in rosacea and psoriasis; however, limited data are available evaluating the use of zinc in these conditions.