A US study has linked frequent permanent hair dye use with a greater risk of breast cancer – but with an important caveat.
A team from the US National Institutes of Health is raising concerns that popular hair dyes and chemical straighteners could increase the risk of developing breast cancer, but don’t go as far as saying their use should stop immediately.
The study, published to the International Journal of Cancer, used data from 46,079 women and found that those who regularly used permanent hair dye in the year prior to enrolling in the study were 9pc more likely to develop breast cancer than women who didn’t.
The study also claimed to find racial differences in the results, with black women who use dyes every five to eight weeks or more associated with a 60pc increased risk of breast cancer, compared with 8pc for white women. Data from the use of semi-permanent or temporary hair dye use showed little or no increase of risk.
“Researchers have been studying the possible link between hair dye and cancer for a long time, but results have been inconsistent,” said corresponding author Alexandra White.
“In our study, we see a higher breast cancer risk associated with hair dye use, and the effect is stronger in African-American women, particularly those who are frequent users.”
As with any study making such a claim, its co-author, Dale Sandler, added caution to the team’s findings. While there is some prior evidence to support an association between breast cancer risk and chemical straighteners, he said, the results need to be replicated in other studies before a definitive answer can be found.
“We are exposed to many things that could potentially contribute to breast cancer, and it is unlikely that any single factor explains a woman’s risk,” Sandler said.
“While it is too early to make a firm recommendation, avoiding these chemicals might be one more thing women can do to reduce their risk of breast cancer.”