Some preliminary evidence supports the use of zinc in the treatment of acne vulgaris and hidradenitis suppurativa, although further studies are necessary to evaluate zinc supplementation in treating inflammatory skin disease, according to a study.
“Zinc appears to have several lines of anti-inflammatory action that involve both adaptive and innate immunity and has been shown to decrease neutrophil chemotaxis, inhibit T helper-17 cell activity and downregulate the expression of Toll-like receptor-2 from keratinocytes,” Raja K. Sivamani, MD, MS, CAT, of the department of dermatology at University of California-Davis, and colleagues wrote.
In a literature review of all articles published before May 29, 2019, researchers identified 22 studies (1,667 patients) that met enrollment criteria assessing zinc supplementation in patients with inflammatory skin diseases including atopic dermatitis, acne vulgaris, diaper dermatitis, hidradenitis suppurativa, psoriasis and rosacea. Of these, 15 studies showed some degree of improvement in the skin condition.
Seven studies used zinc gluconate (10 mg to 90 mg per day), 14 used zinc sulfate (0.375 g to 1.8 g per day) and one study used zinc oxide (0.012 g per day).
Fourteen of the 22 studies assessed the role of zinc in treating acne. In the nine studies comparing zinc to placebo, the overall trend was in favor of the zinc group, according to researchers. However, in Chan and colleagues, it was uncertain whether zinc supplementation alone was responsible for the treatment effect as the active group tested the effect of zinc supplementation in combination with lactoferrin and vitamin E, the researchers wrote.
In three acne studies comparing zinc with antibiotics, there was a greater improvement in the antibiotic groups. Researchers report varying results in three studies comparing zinc with three treatment groups: placebo, vitamin A and zinc/vitamin A. In a study of healthy individuals and patients with acne, researchers found that plasma zinc was initially significantly lower in patients with acne than in healthy individuals and increased in both groups after supplementation. Sebum excretion rate and sebum free fatty acid content were not reduced in either group with zinc supplementation.
Three studies assessed the effect of oral zinc supplementation in adults with hidradenitis suppurativa. Hessam and colleagues found a significant decrease in disease severity, erythema and number of inflammatory nodules. A difference in the number of fistulas or pain intensity was not found. The authors concluded that a combination of zinc gluconate and triclosan could be used as anti-inflammatory treatment for patients with hidradenitis suppurativa in Hurley stage I and II, according to Sivamani and colleagues. Brocard and colleagues proposed that treatment with zinc gluconate was suppressive rather than curative. Dreno and colleagues contradicted previous results with the finding that treatment with zinc gluconate significantly altered the balance of the inflammatory markers in lesional hidradenitis suppurativa skin compared with samples obtained before treatment, according to the researchers.
“While studies in acne vulgaris and hidradenitis suppurativa show particular promise, the evidence is relatively weak or conflicting for its role in the treatment of rosacea, psoriasis, diaper dermatitis and atopic dermatitis,” Dhaliwal and colleagues wrote. “The physiology behind the potential efficacy of zinc in acne and hidradenitis is unclear, although may reflect the anti-inflammatory role of zinc in hair follicle-based diseases.”
The researchers recommend large, controlled studies to further understand the link between inflammatory skin disease and zinc supplementation. – by Abigail Sutton
Disclosures: The authors report no relevant financial disclosures.