Women who use permanent hair dye or chemical hair straightening products have a slightly increased risk of developing breast cancer, according to a new study conducted by the National Institute of Environmental Health Sciences.
After analyzing hair care habits of more than 46,000 women across the U.S. between 2003 and 2009, researchers determined that women who use permanent hair dye are about 9% more likely to develop breast cancer than women who don’t use the dye, according to a December 4, 2019 Insider.com article.
The study suggested that black women may be at greater risk than other women from permanent dyes. Researchers found that black women who dyed their hair at least once in a year had a 45% greater chance of developing breast cancer, compared with 7% higher risk in white women who used permanent hair dye.
The study also found that women who used chemical straighteners every month or two were 30% more likely to develop breast cancer than those who didn’t use the straighteners.
“Just because something’s on the shelf doesn’t mean it’s safe,” said Tamarra James-Todd, Mark and Catherine Winkler Assistant Professor of Environmental Reproductive and Perinatal Epidemiology at Harvard T.H. Chan School of Public Health, who was not involved in the study.
Overall, the risk of developing breast cancer is low among those who use hair dye and straighteners, according to experts.
Read the Insider.com article: Permanent hair dye and straighteners may increase breast cancer risk by messing with our hormones