Twenty healthy women (mean age, 55.3 years) with photoaged skin (damage due to chronic sun exposure) were randomly assigned to apply, in double-blind fashion, a 5% vitamin C cream on one side of their lower neck and arms and a placebo cream on the other side, once a day for six months. Outcome was assessed by a "global score" (a composite score that consisted of the sum of six items: hydration, roughness, laxity, suppleness, fine wrinkles, and coarse wrinkles). Clinical examination by a dermatologist, as well as self-assessment by the volunteers, revealed a significant improvement in global score on the vitamin C-treated side compared with the control side. Application of vitamin C resulted in a significant improvement in both fine and coarse wrinkles. Ultrastructural evidence of elastic-tissue repair confirmed the clinical improvement in the vitamin C group. The treatment was well tolerated.

Comment: This study demonstrates that that topical application of a 5% vitamin C cream is an effective and well-tolerated treatment for photoaged skin. Vitamin C has been shown to reduce oxidative stress in the skin, and also stimulates dermal fibroblasts to synthesize collagen, which may be of value in reversing photoaging. Topical application of vitamin C achieves higher skin concentrations than are obtainable with oral administration. A number of different vitamin C preparations for topical administration are commercially available.

Humbert PG, et al. Topical ascorbic acid on photoaged skin. Clinical, topographical and ultrastructural evaluation: double-blind study vs. placebo. Exp Dermatol 2003;12:237-244.