A New Lawsuit Alleges L’Oréal Downplayed Cancer Risks of Chemical Hair Relaxers

15.09.2026, 02:33 allure.com

A new lawsuit filed Friday has accused L’Oréal USA, the stateside subsidiary of the largest beauty manufacturer in the world, of alleged consumer fraud.

Kris Mayes, attorney general for the state of Arizona, announced the suit, which alleges the company violated the Arizona Consumer Fraud Act with products sold under several brand names, including Dark & Lovely, Optimum, and Mizani. The suit alleges that L’Oréal downplayed the material health risks of the products.

“Defendants have marketed these products to women and young girls of African descent as a safe and desirable means of conforming naturally textured hair to prevailing beauty standards, and have marketed these products to salons as products to be used for the same purpose,” says the suit. “Defendants have done so, even though the use of chemical hair relaxers significantly increases the risk of developing uterine and ovarian cancer,” which the suit characterizes as “a callous disregard for the health of Arizona consumers, particularly women of African descent.”

L’Oréal USA noted that safety is of utmost priority to the company and that they “believe the allegations made in this lawsuit have neither legal nor scientific merit,” in a statement to Allure. “The study upon which this lawsuit is based recognized the need for further research and it made no finding of a causal connection between the use of those products and any conditions alleged by the plaintiffs. Tellingly, while the study clearly states that 'more research is warranted,' one of the lead researchers of the study has also acknowledged that there could be other potential contributing factors to the health outcomes.” (Said researcher has some more recent thoughts on the matter… more on that later.)

It’s not the first time the products have made news. A 2022 study, which first appeared in the Journal of the National Cancer Institute and later published by the National Institutes of Health (NIH) precipitated roughly 60 lawsuits against various producers of hair relaxers. The study’s findings—after following over 33,000 women for almost 11 years—indicated an 80-percent risk increase of uterine cancer among women who had used relaxers at least once in the preceding year. Women that used relaxers more than four times annually had almost double the risk. At that time, the study concluded with, “These findings are the first epidemiologic evidence of association between use of straightening products and uterine cancer. More research is warranted to replicate our findings in other settings and to identify specific chemicals driving this observed association.”

When we first reported on the study, experts weren’t surprised by the correlation between the frequency of hair relaxer use and uterine cancer risk, citing previous research that established a relationship between relaxers and hormonally mediated cancers, like breast and ovarian cancers and uterine fibroids. For the 2022 study, hormonal disruption seemed to be behind the increase in risk for people who used relaxers frequently, which was attributed to “phthalates, parabens, cyclosiloxanes (a type of silicone, used as a solvent, that have also been classified as endocrine disruptors), and metals [like nickel and cobalt, which can at certain levels and in some compounds likely become carcinogenic] and may release formaldehyde when heated,” Alexandra White, PhD, epidemiologist at the U.S. National Institute of Environmental Health Safety, who authored the study, told Allure at the time.

That being said, the experts raised the importance of putting the study’s findings into context. Susan Modesitt, MD, the director of the gynecologic oncology division at Emory University's Winship Cancer Institute and editor-in-chief of Gynecologic Oncology Reports, told Allure that while the study data was "statistically significant," they present "a small attributable—or extra—risk," going on to explain that "people hear 80-percent increased risk and panic, but it's 80 percent of a really tiny risk." In other words, your entire risk isn't 80 percent; it's increased by 80 percent of that 1.64 percent among those who've never used relaxers—an increase of 1.18 percent, which, she says, is still pretty small. (It’s about 3.82 percent.) Dr. White added that it’s important to keep in mind that "chemical hair products are just one of many factors that may influence a woman’s chances of getting uterine cancer.” Things like weight and a sedentary lifestyle play a much larger role (the part of the study L’Oréal is highlighting to support their defense), with Dr. White concluding that “more research is needed before firm recommendations can be made."

What’s interesting is that, since then, more research has shown a higher incidence of uterine cancer for frequent users of hair relaxers, Dr. White adds. Published in 2023, as part of the Black Women’s Health Study, nearly 45,000 women who self-identified as Black, reported their relaxer usage between 1997 and 2019. The key finding was that “long-term use of chemical hair relaxers was associated with increased risk of uterine cancer among postmenopausal women, but not among premenopausal women. These findings suggest that hair relaxer use may be a potentially modifiable risk factor for uterine cancer,” the study says.

“[The study] also looked at the relationship between using these products and a range of other cancers, and we can actually see positive associations between ever using these products and a higher risk of thyroid, pancreatic [cancer] and non-Hodgkin’s lymphoma,” Dr. White, who did not participate in the new research, tells Allure. “Since 2022, the evidence base has grown in terms of other additional studies and the strengthened plausibility that these products are related to different cancer types.”

Dr. White acknowledges that “These are observational studies, so we do the best we can to adjust for other factors that might be influencing it, but that’s the part of the limitation of the study design.” And, of course, it’s tricky to pin a cancer diagnosis to a single thing. What Arizona’s lawsuit alleges, after all, isn’t that the products cause cancer—it’s that L’Oréal USA knew of the risks and chose not to warn its consumers. “L'Oréal knew or should have known about the dangers associated with these toxic hair straightening products,” says Mayes via statement. “Yet, instead of warning their consumers, they put profits over the safety of women and children. That is unacceptable and we will hold them accountable for it.”

For more on breaking beauty news:

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