zeolite. Group of minerals used as an absorbent in cosmetics. Zeolites been shown to have anticancer properties (Source: Journal of Cancer Research and Clinical Oncology, January 2002, pages 37–44).

zinc. There is growing evidence that zinc can be a significant anti-irritant and antioxidant. It also can have anti-acne benefits when combined with a topical antibiotic such as erythromycin. Taken orally, zinc may have positive effects for wound healing and other health benefits (Sources: Dermatologic Surgery, July 2005, pages 837–847; International Journal of Dermatology, September 2002, pages 606–611; and Journal of the European Academy of Dermatology and Venereology, September 1998, pages 13–19).

zinc carbonate. See calamine.

zinc gluconate. Combination of zinc with a form of glucose (a sugar) that is commonly used in cold lozenges for its antiviral effects. A study reported in Dermatology (2001, volume 203, issue 2, page 40) evaluated “the place of zinc gluconate in relation to antibiotics in the treatment of Acne vulgaris. Zinc was compared to minocycline [an antibiotic] in a multicenter randomized double-blind trial. 332 patients received either 30 milligrams elemental zinc or 100 milligrams minocycline over 3 months. The primary endpoint was defined as the percentage of the clinical success rate on day 90….” The study concluded that “Minocycline and zinc gluconate are both effective in the treatment of inflammatory acne, but minocycline has a superior effect evaluated to be 17% in our study.” Whether or not this relates to topical applications is unknown. Note, however, that high doses of zinc can be toxic, so avoid taking more than 100 mg of zinc per day from a supplement (Source: www.drweil.com).

zinc oxide. Inert earth mineral used as a thickening, whitening, lubricating, and sunscreen ingredient in cosmetics. Along with titanium dioxide, zinc oxide is considered to have no risk of skin irritation. It can also be an anti-irritant and potentially an antioxidant (Sources: Journal of Postgraduate Medicine, July 2004, pages 131–139; International Journal of Dermatology, July 2003, page 505; Wound Repair and Regeneration, May 2002, page 130; Alternative Therapies in Health and Medicine, May–June 2001, pages 49–56; and Scandinavian Journal of Plastic and Reconstructive Surgery, December 1994, pages 255–259.) See UVA and zinc.

zinc phenolsulfonate. Antimicrobial agent that can also be a skin irritant.

zinc sulfate. Chemical compound resulting from the interaction of zinc with sulfuric acid. There is little research showing this to be beneficial for skin. The little information that is available shows that it does not help skin healing (Source: Acta Dermato-Venereologica, 1990, volume 154, Supplemental, pages 1–36) and it can be a skin irritant. See zinc.

Zingiber officinale Roscoe. See ginger extract.

Zingiber zerumbet. See ginger extract.

Zingiberaceae. See ginger extract.