A study from theNational Institutes of Health(NIH) finds women who use permanent hair dye and chemical hair straighteners have a higher risk of developing breast cancer than women who don't use the products.
Citing data from a sister study of 46,709 women, scientists found women who regularly used permanent hair dye in the year before enrolling in the study were 9% more likely to develop breast cancer than women who did not use the products.
African American women who used permanent dyes every 5 to 8 weeks or more were associated with a 60% increase of risk of breast cancer compared to an 8% risk among white women.
Researchers say they found little to no increased risk of breast cancer for semi-permanent or temporary dye use.
Use of chemical hair straighteners every 5 to 8 weeks was found to increase breast cancer risk by 30% among all women, though use of straighteners was more common among African American women.