Permanent Hair Dyes and Chemical Straighteners May Be Linked to Breast Cancer, Study Says

Two common beauty products—permanent hair dyes and chemical straighteners—may be associated with an elevated risk for breast cancer, according to a new study published in the International Journal of Cancer. Hair dyes have been linked to other cancers before, though the research is inconclusive. Bladder and blood cancers have been examined most closely, according to the American Cancer Society, with the most consistent results pointing to a small increase in bladder cancer risk for salon employees. Meanwhile, most studies to date looking specifically at dye and breast cancer have not found a connection. The picture is similarly unclear for hair straighteners. While a major study using data from the mid-1990s did not find a link between straighteners and breast cancer, other, more recent studies have—and the researchers behind the new paper note that some straightening formulas popularized since the 1990s, namely keratin treatments, have been found to either contain the carcinogen formaldehyde, or release it during the application process. The new study, which was funded by the National Institutes of Health (NIH) and the National Institute of Environmental Health Sciences, tracked 46,700 U.S. women enrolled in the Sister Study, which recruited breast-cancer-free women whose sisters had been diagnosed with the disease. At enrollment, the women ranged in age from 35 to 74. They answered questions about their health, lifestyle (including hair product use) and d...
Source: TIME: Health - Category: Consumer Health News Authors: Tags: Uncategorized Cancer Source Type: news