According to a large study by the National Institute of Environmental Health Sciences, chemical hair straighteners, relaxers, and dyes may increase the risk of certain cancers. Although scientists don’t know how these products contribute to cancer, some chemical ingredients may impair the endocrine system.
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hair products and Cancer
The study tracked 33,000 women, their hair product use, and their health conditions over 11 years. Uterine cancer developed in 1.6% of women who never used chemical hair straighteners. Women frequently using chemical hair straighteners have a higher risk of uterine cancer. Uterine cancer already disproportionally affects Black women.
Cancer risk has been linked to chemical hair products before. A National Institutes of Health study published in 2020 linked chemical hair dyes and straighteners to breast cancer risk. These hair products can also cause breast cancer in Black women. Frequently using chemical-based hair products increases breast cancer risk in women of color.
Nicole Deziel, Yale Cancer Center Professor, said the research evidence supports the growing list of harmful beauty product ingredients. Hair-straightening products contain toxic and hormone-disrupting chemicals that women repeatedly use in the early stages of their lives.
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How These Products May Lead To Cancer
The research on chemical-based hair straighteners is still in its early stages, so it’s unclear how they contribute to cancer, says Stanford University’s Dr. Oliver Dorigo.
There are known carcinogens in many chemical-based straighteners. Some chemicals, including metals, phthalates, and parabens, disrupt estrogen levels in the body, resulting in hormonal imbalances. Excess estrogen is associated with hormone-influenced breast, ovarian, and uterine cancers. Hormonal changes also affect the uterus.
A number of the ingredients in these products may stimulate the endometrium, which is especially responsive to estrogen,” Dorigo said. This can cause cancerous thickening of the uterine lining in some cases.