A new study by researchers at Boston University finds a possible link between the heavy use of lye-based hair straightening products, or relaxers to a greater risk of breast cancer for African American women.
Researchers used data from Boston University’s Black Women’s Health Study which has documnted the health of 59,000 African American women for over 25 years. They found that 5 percent of the African Americans women participants in the study never used hair relaxers, 5 percent were light users, 70 percent were moderate users, and 20 percent were heavy users. Heavy users were Black women who used hair products containing lye at least seven times a year for 15 or more years.
Comparing user data to incidence of breast cancer, the researchers found that Black women who were heavy users of hair relaxers had an approximately 30 percent increased risk of estrogen receptor positive breast cancer compared to other Black women.
The authors conclude that “given the high prevalence of use of these products among Black women, further research is warranted to better establish associations according to breast cancer subtype as well as according to specific products.”
The study, “Hair Product Use and Breast Cancer Incidence in the Black Women’s Health Study,” was published on the website of the journal Carcinogenesis. It may be accessed here.