Chemical Hair Straighteners and the Risk of Uterine Cancer: The Black Women’s Health Study

Chemical hair straighteners, commonly known as hair relaxers, have long been favored by women with curly, textured hair. These products, designed to straighten and smooth natural hair, have been aggressively marketed to women of color as a means of achieving what society deems a more “desirable” hairstyle. However, recent studies have raised concerns about the potential health risks associated with the use of chemical hair straighteners and relaxers, particularly among Black women. In the Black Women’s Health Study, a cohort study of more than 44,000 Black women, researchers found an increased risk of uterine cancer associated with long-term use of hair relaxers among postmenopausal Black women. 

What are Chemical Hair Straighteners?

Chemical hair straighteners or relaxers are products commonly used to straighten curly or tightly coiled hair. These products work by breaking down the protein structure in the hair, altering its natural texture, and making the hair straight. Hair relaxers are widely marketed and commonly used by women, primarily Black women, as a means of achieving straighter, smoother hair. Popular brands of chemical hair straighteners include Dark & Lovely, ORS Olive Oil, L’Oreal, and Revlon.

The Link Between Hair Relaxers and Uterine Cancer

Several recent studies have examined the potential health risks associated with the use of chemical hair straighteners, most notably uterine cancer. The Black Women’s Health Study (BWHS), conducted by researchers at Boston University, has provided significant insights into this issue. The study followed 44,798 women with an intact uterus who self-identified as Black for up to 22 years, beginning in 1997, when chemical hair relaxer use was queried, and ending in 2019. 

The study authors found a higher rate of uterine cancer among postmenopausal women who reported long-term and heavy use of hair relaxers. “In this large cohort of Black women, long-term use of chemical hair relaxers was associated with increased risk of uterine cancer among postmenopausal women, but not among premenopausal women,” the researchers wrote. “These findings suggest that hair relaxer use may be a potentially modifiable risk factor for uterine cancer.”

Breaking Down the Study Findings

The BWHS study revealed that postmenopausal Black women who used chemical hair relaxers more than twice a year or for more than five years had a greater than 50% increased risk of developing uterine cancer compared to those who rarely or never used relaxers. The risk was even higher for women who reported using hair relaxers for more than 10 years, regardless of frequency. Moderate use of hair relaxers was associated with a 60% increased risk, while heavy use and use for 20 years or more increased the risk by 64% and over 70% respectively.

The study also highlighted the significant racial disparities in uterine cancer. Black women have higher rates of aggressive subtypes of uterine cancer and are nearly twice as likely to die from the disease compared to non-Hispanic white women. This further emphasizes the importance of understanding the potential health effects of hair relaxer use and addressing the underlying factors contributing to these disparities.

The Potential Dangers of Chemical Hair Straighteners

Chemical hair straighteners contain endocrine-disrupting chemicals, such as phthalates and parabens, which can interfere with the normal functioning of the endocrine system. These chemicals can be absorbed through the skin when the products are applied to the scalp and may be responsible for the development of certain cancers, such as uterine cancer.

In addition to the increased risk of uterine cancer, research has suggested that chemical hair straighteners may contribute to other health problems. Studies have shown a potential link between hair relaxer use and the development of breast cancer, uterine fibroids, and early onset of puberty in girls. These findings raise concerns about the overall safety of chemical hair straighteners and their potential long-term effects on women’s health.

Calls for Stricter Regulations and Safer Alternatives

The growing body of research highlighting the potential risks of chemical hair straighteners has led to calls for stricter regulations and the identification of safer alternatives. Currently, cosmetic products, including hair relaxers, are poorly regulated by the federal government in terms of ingredient safety. This lack of oversight leaves consumers unaware of the potential harm associated with these products.

To address these issues, researchers and policymakers have suggested several measures. Stricter regulation of cosmetic products, including hair relaxers, could help ensure the safety of consumers. Additionally, raising awareness about the potential health risks of chemical hair straighteners is crucial to empower individuals to make informed choices about their hair care practices. Efforts such as the CROWN Act, which prohibits discrimination against natural hair, and the FDA’s proposed ban on hair-smoothing products containing formaldehyde are steps toward reducing racial disparities and protecting the health of Black women and other women who use chemical hair straighteners.

Seeking Legal Recourse for Hair Relaxer Side Effects

As awareness about the potential side effects of chemical hair straighteners grows, thousands of women have filed lawsuits against manufacturers of popular hair relaxer brands. These lawsuits allege that the companies failed to adequately warn consumers about the presence of endocrine-disrupting chemicals in their products, which may contribute to the development of uterine cancer, ovarian cancer, uterine fibroids, and other complications. The ongoing hair relaxer litigation aims to hold these companies accountable for the harm caused to consumers.