Women who routinely use permanent hair dye may have a higher risk of breast cancer, according to research conducted by a team including Ms. Carolyn Eberle, a doctoral student of epidemiology at the University of North Carolina Gillings School of Global Public Health.
A recent study based on the large Sister Study cohort of more than 46,000 women found a connection between permanent hair dye and breast cancer — particularly among African-American women.
Overall, study participants who regularly dyed their hair with permanent dye had a 9 percent greater risk of developing breast cancer. For African-American women, the risk was 45 percent higher. (The risk increased even further, to 60 percent, among African-American women who used permanent hair dye very frequently — defined as at least every five to eight weeks.)
The researchers found little to no increase in breast cancer risk with the use of semi-permanent or temporary dye.
First author Ms. Eberle worked with senior author Dr. Alexandra White — an alumna of the Gillings School’s epidemiology department who is now the head of the Environment and Cancer Epidemiology Group at the National Institute of Environmental Health Sciences — and with Dr. Dale Sandler and Dr. Kyla Taylor to conduct the research. Their report was published online December 4 by the International Journal of Cancer.
The Sister Study, a national cohort study of 50,884 women ages 35 to 74 years old, enrolled women from 2003 to 2009. All Sister Study participants had a sister with breast cancer but were free of breast cancer themselves.
The researchers also found an association between the use of chemical hair straighteners and breast cancer, with women who used straighteners at least every five to eight weeks being about 30 percent more likely to receive a breast cancer diagnosis.Friday Letter Submission, Publish on January 03