As of late, there has been a renewed interest in estrogens through the phytoestrogens contained in soy.
Q. What is unique about the new skin softening body lotions?
Q. What is the most effective topical cosmeceutical?
Estrogen creams have a rich history in cosmetic dermatology. At the time the Cosmetics and Toiletries Act was penned in the 1930s, hormone creams were the most popular cosmeceutical facial moisturizers. Both estrogen and progesterone creams were on the market and available for over-the-counter purchase. The introduction of legislation defining cosmetics as products that do not alter the structure or function of the skin reclassified hormone creams as drugs, and they were removed from the consumer market.
There is no doubt that estrogen creams produce increased dermal collagen production, but they carried with them the side effects of facial telangiectasia. There also was some concern that estrogen might increase the risk of malignant melanoma. However, a study by Smith et al demonstrated no link between melanoma and oral contraceptives or replacement estrogens.
As of late, there has been a renewed interest in estrogens through the phytoestrogens contained in soy. Phytoestrogens, such as genistein, daidzein and glycitein, are found in fermented soy and can be consumed in the form of roasted soy nuts or tofu. Soy protein supplements have been investigated for their benefit in a variety of postmenopausal symptoms, but the data is somewhat inconsistent. One controlled study by Kotsopoulos et al found that a soy protein supplement had no statistically significant effect over placebo on dry skin. Yet, genistein is one of the most popular botanical additives to skincare products promising to decrease the appearance of fine lines on the face.
It can be difficult, however, to determine if the decreased wrinkling advertised by the manufacturer is due to the vehicle moisturizer decreasing lines of dehydration and altering light reflection from the skin surface, or to true changes in skin collagen production and increased dermal thickness. Thus, the exact effect of soy phytoestrogens on the skin is hard to determine.
In the current regulatory climate, no cosmetic manufacturer wants to determine the answer to this question. Moisturizing the skin and changing optical characteristics is the realm of cosmetics, but enhancing collagen production is the realm of a drug. Any soy product that documented increased collagen production would certainly be removed from the market by the U.S. Food and Drug Administration. It is for this reason that research is lacking in the topical application of phytoestrogens.
Will topical estrogen creams ever be introduced into the prescription market? It is unlikely. Estrogen cream by itself is not patentable and the legal risks are tremendous. It would be very difficult to market a product that potentially could worsen the severity of breast cancer. Furthermore, over-the-counter sale of estrogen cream would make the product available to pregnant women, prepubertal girls and males. All of these would be considered high-risk users. No, estrogen cream will not be the rediscovered cosmeceutical.
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1 Smith MA, Fine JA, Barnhill RL, Berwick M. Hormonal and reproductive influences and risk of melanoma in women. Int J Epidemiol. 1998; Oct 27(5):751-757.