Finding truth among cosmeceutical companies' claims a complicated task

March 1, 2010

Cosmeceuticals carry the promising suggestion of providing cosmetic treatments with active ingredients that give them pharmaceutical-like efficacy to address skin aging and skin problems. Dermatologists are faced with the unique challenge of wading through these claims.

Key Points

National report - Cosmeceuticals carry the promising suggestion of providing cosmetic treatments with active ingredients that give them pharmaceutical-like efficacy to address skin aging and skin problems. Dermatologists are faced with the unique challenge of wading through these claims.

When credible evidence exists, though, it improves the likelihood that physicians will hear about it and explore these products.

In treating wrinkles, for instance, the hands-down winners in terms of evidence of efficacy are topical retinoids, and, to a slightly lesser extent, glycolic acid, says Leslie Baumann, M.D., a Miami-based dermatologist in private practice.

Big claims, little research

Cosmeceutical products with biologically active ingredients ranging from free-radical-reducing antioxidants to collagen-building peptides are heavily promoted to consumers with scientific-sounding claims. Many of these products, however, carry little or no clinical research to back the claims.

To the Food and Drug Administration, the products are classified as cosmetics, with no scientific evidence required to support their claims.

That doesn't mean all cosmeceuticals are ineffective, but it can make it difficult for consumers and physicians to differentiate the ones that work from those that don't.

Retinoids remain one of the only cosmeceuticals to carry proof of efficacy in treating wrinkles. They also play a role in the prevention of wrinkles, as do a variety of sunscreens. To prevent wrinkles and skin cancer caused by the sun, sunscreens need to effectively block not only sunburn-causing UVB rays, but also rays from the UVA spectrum, which can cause skin aging and cancer.

New UV blockers

Two relatively new sunscreen ingredients shown to block UVA include ecamsule, used in L'Oréal sunscreens, and photostabilized avobenzone, found in Neutrogena products.

"Ecamsule and photostabilized avobenzone both block UVA, and I think we will see more and more advances in photoprotection as sunscreens are developed to block broader and broader bands of radiation," says Zoe Draelos, M.D., a consulting professor of dermatology, Duke University, Durham, N.C.

Antioxidants, though one of the most popular ingredients in cosmeceuticals, have variable evidence of efficacy in skin aging. Among antioxidants with the most promising evidence are a class of berry extracts that are a class of flavonoids called anthocyanins, derived from berries, Dr. Draelos says.

Rosacea relief

In the treatment of rosacea, several cosmeceuticals offer anti-inflammatory properties that show some efficacy.

Among those with the most data are licorice extract, found in Eucerin's Redness Relief products; feverfew PFE (parthenolide-free extract), found in Aveeno's Ultra-Calming collection; and niacinamide, an ingredient in Olay's Regenerist product line, Dr. Baumann says.

"For rosacea, you want anti-inflammatory ingredients, and all of these have some clinical data," she says.

For pigmentary problems, treatments such as prescription hydroquinone or kojic acid can be effective. Soy, found in some Neutrogena and Aveeno products, and niacinamide, in Olay's Regenerist, also can help.

Dr. Draelos notes that a new hydroquinone-free skin-lightening combination treatment based on kojic acid and emblica showed impressive results in recent studies.

"I tested this combination against hydroquinone, and by the end of 12 weeks, parity was demonstrated between 4 percent hydroquinone and the botanical formulation, but it took a little longer to take effect, likely because hydroquinone is a prescription agent," she says.

For the treatment of stretch marks, Merz has launched a new product containing centella asiatica, or Indian pennywort, which is said to help induce fibroblast migration.