Hair Relaxer Chemicals and Cancer: Understanding the Potential Risks

Seeking the perfect hair texture has led many to turn to chemical-based hair relaxers, a choice embraced by millions. In 2020 alone, Statista reported a staggering 10.38 million Americans opting for home hair permanents and relaxers.

Yet, while these products promise temporary straightening, an alarming concern looms over their chemical makeup. There’s an escalating worry about potential health risks, especially their alleged connection to cancer, casting a shadow over their allure.

In this article, we’ll delve into the cancerous effects of hair relaxer chemicals, shedding light on the research findings and implications for consumers’ health.

Chemicals in Hair Relaxers Linked to Cancer

Hair relaxers contain various chemicals known for their hair-straightening properties. Some of the primary chemicals, such as formaldehyde, lye (sodium hydroxide), and other harsh alkaline compounds, have raised concerns regarding their potential carcinogenic effects.

While the evidence linking these chemicals directly to cancer is not conclusive, several studies have emphasized potential associations between certain ingredients in hair relaxers.


Formaldehyde, a known carcinogen, is not typically listed as an ingredient in hair relaxers. However, some formulations release formaldehyde gas when heated, as is the case in some keratin-based treatments or Brazilian blowouts. Prolonged exposure to formaldehyde has been linked to an increased risk of certain cancers, including uterine cancer and leukemia.

Lye (Sodium Hydroxide) and Other Alkaline Compounds

Hair relaxers containing lye or other strong alkaline compounds are known for their ability to break down hair’s protein structure. While direct links between these chemicals and cancer haven’t been firmly established, frequent exposure to such harsh substances may potentially irritate the scalp. This increased irritation can raise the risk of skin damage and potentially lead to other health complications.

Research Findings and Concerns

According to the American Cancer Society, a recent study conducted by researchers at the US National Institutes of Health (NIH) unveiled a potential link. This connection was identified between women using chemical hair straighteners and relaxers and an increased risk of uterine cancer.

The study, published on October 17, 2022, in the Journal of the National Cancer Institute, utilized data from over 33,000 women. These women were participating in the Sister Study, a comprehensive ongoing research initiative dedicated to identifying breast cancer risk factors and other health conditions.

At the commencement of the study, participants were asked about their use of various hair products over the preceding year. These products included hair dyes, straighteners, relaxers, permanents, or body waves

Following nearly 11 years of follow-up on average, women who reported using hair straightening products displayed an almost twofold likelihood of developing uterine cancer. The results were compared to those who did not use such products, even after adjusting for other influencing factors.

Additionally, women who frequently used straighteners, more than four times in the prior year, showed a significantly increased likelihood. This was roughly 2.5 times higher in terms of developing uterine cancer.

Moreover, as reported by NBC News, in a study of 44,798 Black women, researchers observed a heightened incidence of uterine cancer. This elevated occurrence was particularly notable among postmenopausal Black women. The study identified an increased risk among those who reported using chemical hair relaxers for a minimum of 10 years, regardless of usage frequency.

Regrettably, the alarming data has resulted in legal repercussions, with individuals attributing their illnesses to these products and pursuing legal action against manufacturers.

According to Drugwatch, as of November 16, 2023, there were 7,967 pending lawsuits concerning hair straightener cancer in multidistrict litigation. Additionally, the total count of filed cases stood at 8,026 in the U.S. District Court of the Northern District of Illinois.

Attorneys anticipate a surge in filings for chemical hair straightener lawsuits and are actively accepting new cases. According to TorHoerman Law, as of now, there haven’t been any trials or global settlements approved within the Illinois MDL.

Take of Regulatory Bodies

The FDA has set forth a proposed rule aimed at prohibiting formaldehyde-based hair products, potentially taking effect as early as April 2024.

The FDA’s proposed regulation aims to prohibit the use of formaldehyde (FA) and related FA-releasing chemicals like methylene glycol. These substances would be barred from being used as ingredients in hair smoothing or straightening products sold in the United States.

Dr. Christopher Bunick, a dermatologist at Yale Medicine, perceives the FDA’s action as a significant step. He believes it will aid in safeguarding consumers from carcinogenic elements commonly present in various over-the-counter products.

Dr. Bunick expresses hope for ongoing advocacy within Congress. He emphasizes the significance of advocating for improved quality control measures in the manufacturing of non-prescription personal care items.

Protecting Health and Exploring Alternatives

Given the potential risks associated with hair relaxer chemicals and their potential links to cancer, individuals concerned about their health may consider alternatives:

  • Natural Hair Care: Embracing natural hair textures and styles that don’t require harsh chemical treatments.
  • Chemical-Free Products: Exploring safer, chemical-free hair care options that utilize natural ingredients to manage hair without exposure to potentially harmful substances.
  • Regular Health Screenings: Being vigilant about health check-ups and discussing any concerns with healthcare professionals to monitor and address potential risks.

In conclusion, while the direct correlation between hair relaxer chemicals and cancer is not fully established, emerging research suggests potential associations. As consumers, it’s crucial to prioritize health and make informed choices regarding hair care routines.

Exploring alternative methods that prioritize hair health without relying on harsh chemicals can help individuals safeguard their well-being while maintaining their desired hair aesthetics.

Regular health monitoring and staying informed about the latest research findings empower individuals to make proactive decisions for their overall health and well-being.