Women who dye or straighten hair could have increased breast cancer risk

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A study of almost 50,000 women found a nine percent increased risk of breast cancer linked to those who used permanent hair dye and an 18 percent risk for those who used chemical straighteners. Those numbers went up for women who used the products more frequently and for African-American women. The study’s authors caution they have not proven these hair treatments cause cancer, but say the more than 5,000 chemicals in hair products could be a risk factor.