Breast cancer patients who apply moisturizers may be dosing themselves with estrogen without even knowing it investigators reported at the San Antonio Breast Cancer Symposium. Dr. Adrienne Olson, a researcher with Breastlink in Rancho Palos Verdes, California and her colleagues analyzed 16 widely available moisturizers for estrogens. None of the creams analyzed listed estrogen as a content in their list of ingredients, however six samples contained estriol or estrone; two out of the three powerful estrogens produced by women’s ovaries.
Dr. Olson became interested in the estrogen-moisturizer association while she was being treated for estrogen receptor-positive breast cancer. The chemotherapy caused her skin to become dry and wrinkled. So she began using a moisturizer to help restore her skin's natural appearance. In fact, the moisturizer worked so well that she suspected the product might contain estrogen, which helps maintain skin integrity and promote a "youthful appearance."
Following up on her suspicions, Dr. Olson collected containers of 16 nonprescription skin moisturizers, spanning a wide cost range. She sent the samples to a research laboratory, which tested the products for the presence of a woman’s most powerful estrogens; estradiol, estrone, and estriol. Analysis by high-performance liquid chromatography (NPLC) revealed estrone at a concentration of 0.05% in one of the products and estriol in five others at concentrations ranging from 0.17% to 0.61%. Some of the other products might contain lower levels of the hormones that were not detected by HPLC, she added. Moreover, the product analysis did not include testing for customized or designer estrogens.