Study: Permanent hair dyes linked to breast cancer

Two common beauty products, permanent hair dyes and chemical straighteners, may be associated with an elevated risk for breast cancer, a new study said.

The study, published in the International Journal of Cancer, tracked more than 46,000 women over several years.

Overall, women using permanent dye had a 9% higher risk of developing breast cancer.

Black women who used permanent dye had a 45% higher risk of breast cancer compared to non-users, and those who used the products every for eight weeks or more often had a 60% higher risk.

The study was funded by NIH and recruited breast cancer-free women whose sisters had been diagnosed with the disease.

Women in the study ranged in age from 35 to 74.

The study says more research is needed.