With thousands of active ingredients available in cosmeceutical products, one expert recommends starting with vitamin A and its derivatives, then adding hydroxy acids and perhaps antioxidants for patients who desire even more anti-aging effects. He gives all his patients a sunscreen.
Cleveland - Because patients expect advice regarding cosmeceutical products from their dermatologists, these specialists must be able to deliver effective guidance in this area, an expert says.
"Patients will consider their dermatologist an expert in cosmeceuticals whether one is or not. So one definitely must know at least a little bit about them, because our patients are already using them at home," says Malcolm Ke, M.D., assistant professor, department of dermatology, Case Western Reserve University, Cleveland.
"Whether the active ingredients really have a biologic effect is not certain at this point, but the theory and mechanisms behind some of them make sense," which explains their growing popularity, says Dr. Ke, who spent 2005 as the surgical, laser and aesthetic fellow in the Hollywood-area practice of Gary P. Lask, M.D., clinical professor and director of the dermatologic surgery service at the University of California, Los Angeles, David Geffen School of Medicine.
Vitamin A and its derivatives - the most common ingredient in cosmeceutical products - are also backed by the most evidence, Dr. Ke tells Dermatology Times.
"Not just vitamin A, but derivatives such as retinol have been shown in some trials to improve the clinical effects of aging," he notes.
Similarly, Dr. Ke says alpha, beta and polyhydroxy acids, the second-most-common ingredient in cosmeceutical products, have both keratolytic properties and evidence-supported capabilities such as increasing the expression of collagen mRNA and collagen growth.
However, he adds, "It gets somewhat fuzzier when we talk about antioxidants. Mechanistically, it makes sense to use a lot of these in our cosmetics. But evidence of whether they have a true biologic effect" remains to be seen.
Particularly common ingredients include nonenzymatic antioxidants, such as vitamin C, vitamin E, ubiquinol, glutathione and alpha-lipoic acid, Dr. Ke says.
"Vitamin C is not just an antioxidant," he adds, "but it's also a sunscreen," though it is weak. "And it's very compatible when used with vitamin E because it regenerates it to its oxidative form," Dr. Ke says.
"Vitamin E is most abundant in the stratum corneum, making it naturally the first line of defense against much of the environmental oxidative stress that we see," he adds.
In early 2007, Dr. Ke's staff performed an informal survey of Los Angeles cosmetologists working at two high-end department stores, as well as at a local discount store, to gauge various products' popularity and market recognition.
The top two finishers were:
A newcomer on the market with a growing presence is the direct-to-consumer form of Prevage (Allergan), Dr. Ke adds.
At $150 a bottle, "It contains green tea extracts and the potent antioxidant idebenone, a synthetic analogue of ubiquinone, which is found in the popular Coenzyme Q," Dr. Ke says. However, he adds, "It seems to have greater penetration due to its smaller molecular weight, and greater antioxidant properties, than ubiquinone."