In September 2025, the Journal of the National Cancer Institute (JNCI) published a new study linking the use of chemical hair relaxers to an increased risk of thyroid cancer, pancreatic cancer, and non-Hodgkin’s lymphoma—a common type of blood cancer.
To reach these findings, researchers analyzed data obtained from the Sister Study, a nationwide cancer research effort organized by the National Institutes of Health (NIH). Over 45,000 cancer-free women between ages 35-74 were enrolled in the study from 2003-2009, providing health updates to researchers for an average follow-up period of 13 years. Data from the Sister Study was also used when hair relaxer exposure was first linked to an increased risk of uterine cancer back in 2022.
What were the study’s results?
During enrollment, participants were asked to report how many times they used chemical hair relaxers within 12 months prior to joining the study. About 11% of participants in the study reported using hair relaxers at least once, while the remaining 89% claimed to have not used them at all.
Though further research will be needed to confirm these findings, researchers identified a general trend suggesting that the 11% of participants who used hair relaxers before the study had an increased risk of developing thyroid cancer, pancreatic cancer, and non-Hodgkin’s lymphoma.
Thyroid Cancer
According to the JNCI, using chemical hair relaxers could be linked to a “higher incidence” of thyroid cancer with a hazard ratio (HR) of 1.71 and a 95% confidence interval (CI). In other words, using hair relaxers could potentially increase your risk of developing thyroid cancer by 71%, compared to not using hair relaxers at all.
Pancreatic Cancer
Using chemical hair relaxers was also associated with a higher incidence of pancreatic cancer (HR:2.66, 95% CI [1.25-5.66]), especially if relaxers were used more than 4 times a year. Therefore, hair relaxer exposure could be potentially linked to a 166% increased risk of pancreatic cancer.
Pancreatic Cancer
Finally, chemical hair relaxer exposure was linked to a higher incidence of non-Hodgkin’s lymphoma (HR:1.62, 95% CI [0.94-2.80]). Based on this data, using hair relaxers could potentially increase your risk of developing non-Hodgkin’s lymphoma by 62%.
Can I join the lawsuit if I have one of these cancers?
Unfortunately, not yet. Because this is the first medical study to suggest a link between using hair relaxers and developing a non-reproductive type of cancer, more evidence will be needed before attorneys can begin accepting these cancers for the lawsuit. But, now that academic research has suggested that this connection is possible, lawyers may be able to accept cases for thyroid cancer, pancreatic cancer, and non-Hodgkin’s lymphoma sometime in the future.
Currently, the only conditions that can qualify for the hair relaxer lawsuit are:
- Uterine Cancer
- Endometrial Cancer
- Ovarian Cancer (all subtypes)
- Fallopian Tube Cancer
- Primary Peritoneal Cancer
File a hair relaxer claim
If you or an immediate family member were diagnosed with uterine cancer or another reproductive cancer after using hair relaxers, you may be entitled to significant compensation from the lawsuit.
Ready for a free case review? Take our online hair relaxer eligibility evaluation to see if you may be eligible to file a claim.
