Hair Relaxer Lawsuits 2026: What the New Research Shows

Last updated: October 2026

Hair relaxer lawsuits in 2026 rest on a growing body of research. A major 2022 National Institutes of Health study linked frequent use of chemical hair straighteners to a higher risk of uterine cancer, and other studies have tied these products to ovarian and breast cancer. Researchers have also found that Black women use these products most and may face the highest exposure. It also explains how to rebuild your product history and how courts weigh this science in hair relaxer lawsuits 2026.

This article walks through what the studies found, what they do not prove, and where federal rules on formaldehyde stand. It focuses on the science, not the court case count.

Why research is at the center of hair relaxer lawsuits

The lawsuits claim that makers of chemical relaxers and straighteners knew, or should have known, that their products could raise cancer risk and did not warn users. The companies deny that their products cause cancer.

In product cases like this, science plays a big role. Courts look at whether studies show a reliable link between a product and an illness. That is why each new study draws attention from doctors, patients and lawyers alike.

If you want to know how many cases have been filed and how the federal case has grown, see our hair relaxer MDL case count update. Here, we stay with the research.

The 2022 NIH Sister Study: uterine cancer

The study that changed the conversation came out in October 2022 in the Journal of the National Cancer Institute. It used data from the Sister Study, a long-running NIH project that tracks the health of women whose sisters had breast cancer.

Here is what the NIH reported about the uterine cancer findings:

• Researchers followed 33,497 U.S. women, ages 35 to 74, for almost 11 years.
• 378 of those women were diagnosed with uterine cancer during that time.
• Women who used straightening products more than four times in the prior year were more than twice as likely to develop uterine cancer as women who never used them.
• By age 70, an estimated 1.64% of never-users would develop uterine cancer, compared with 4.05% of frequent users.

The researchers did not find the same link for other hair products they asked about, such as dyes, bleach, highlights or perms.

They also noted that uterine cancer is still fairly rare. It makes up about 3% of new cancer cases. The authors said more research is needed to confirm the findings in other groups of women.

Later studies on ovarian and breast cancer

The uterine cancer study did not stand alone. The same Sister Study group had already looked at other cancers that affect women.

Ovarian cancer

A 2021 study in the journal Carcinogenesis looked at 40,559 Sister Study participants. Frequent use of straighteners, relaxers or pressing products, more than four times in the past year, was linked to about twice the risk of ovarian cancer.

Breast cancer

A 2019 study in the International Journal of Cancer followed nearly 47,000 Sister Study participants. According to the National Institute of Environmental Health Sciences, women who used chemical straighteners at least every five to eight weeks had about a 30% higher risk of breast cancer. The link was similar for Black and white women, though Black women used straighteners far more often.

Other cancers in newer research

A 2025 Sister Study analysis, also published in the Journal of the National Cancer Institute, looked beyond reproductive cancers. It reported possible links between straightener use and pancreatic and thyroid cancer. The authors cautioned that some results were imprecise and that too few cases were seen among Black women to draw firm conclusions for that group.

What the research says about Black women’s exposure

One pattern shows up again and again: Black women are the most frequent users of chemical relaxers. Many start as children and continue for decades.

• In the 2022 NIH study, about 60% of participants who reported using straighteners in the prior year identified as Black women.
• In the Black Women’s Health Study, researchers followed 44,798 Black women from 1997 to 2019. A 2023 analysis in Environmental Research found no clear link to uterine cancer across the whole group. But among postmenopausal women, those who had used relaxers for 20 years or more had a higher risk.
• In product testing, a 2018 study by the Silent Spring Institute tested 18 hair products used by Black women and found 45 chemicals that can disrupt hormones. Relaxers made for children had some of the highest levels of chemicals that are banned in Europe or regulated in California. Most of the chemicals found were not listed on the label.

Researchers say earlier and longer use may mean more lifetime exposure. That could help explain why the findings matter so much to Black communities, and why scientists keep calling for more study.

Which chemicals are under study, and the FDA formaldehyde status

The studies above did not test specific brands. But the NIH researchers noted that straighteners can contain chemicals of concern, including:

• Parabens
• Bisphenol A (BPA)
• Metals
• Formaldehyde, which some smoothing products release when heated

Several of these can act like hormones in the body. Scientists think that may matter for cancers of the uterus, ovaries and breast, which are sensitive to hormones.

Where the FDA formaldehyde ban stands

The FDA has warned that hair smoothing products can release formaldehyde when heated. Formaldehyde is classified as a human carcinogen. On labels, it may appear as formaldehyde, formalin or methylene glycol.

The FDA first said it planned to propose a ban on formaldehyde and formaldehyde-releasing chemicals in hair smoothing and straightening products in 2023. That target has been pushed back several times. The latest federal regulatory agenda, released in July 2026, lists November 2026 as the target for the proposed rule.

As of early October 2026, no proposed rule has been published. Even once it is, a proposal is not final. The public can comment, and the FDA would then need to issue a final rule.

It is also worth knowing that most of the lawsuits involve relaxers, which work differently from formaldehyde-based smoothing treatments. A formaldehyde rule would not settle questions about other chemicals in relaxers.

What the research does and does not prove

These studies are serious, but it helps to read them carefully.

• Links are not proof of cause. The studies show an association. They do not prove that relaxers caused any one person’s cancer.
• Relative vs. actual risk. “Twice as likely” sounds large. For uterine cancer, it means an estimated 4.05% risk by age 70 for frequent users, compared with 1.64% for never-users.
• Memory matters. Most studies asked women to recall past product use, which can be hard to do accurately.
• More study is coming. Scientists have called for research that looks at specific ingredients and longer use.

Courts will weigh this science as the cases move forward. For people who used these products and later got sick, the research is one reason to ask questions about their own history.

How to Rebuild Your Product History for Hair Relaxer Lawsuits 2026

The studies above asked women to remember how often they used straighteners. Claims work in a similar way. In hair relaxer lawsuits 2026, a person’s own history of use is often one of the first things a law firm asks about.

Many people started using relaxers as children and stopped years ago. You may not remember every detail, and that is normal. The goal is to rebuild what you can, as honestly as you can.

Start with a simple timeline

Write down the years you used relaxers or straighteners, even if you can only guess the decade. Then add details for each period:

• The brand names or product lines you remember
• Whether you used home kits, salon treatments or both
• How often you had a touch-up, such as every 6 to 8 weeks
• The name and city of any salon you went to regularly
• When you stopped, and why

Look for reminders

Old photos can help you date when your hair was relaxed, which can be useful for hair relaxer lawsuits 2026 claims. Family members, friends and longtime stylists may remember brands or routines you have forgotten. Some people still have old product boxes, receipts, store loyalty records or bank statements that show purchases.

Be careful not to guess

If you are not sure about a brand or date, write “not sure” rather than filling in a guess. In hair relaxer lawsuits 2026, details are often compared against other records later. A careful “I don’t remember” is better than a confident detail that turns out to be wrong.

If a loved one has passed away

Sometimes the person who used relaxers has died. Family members may still be able to rebuild a history. Sisters, daughters and close friends often remember salon visits, home kits and how long the routine lasted. Some families involved in hair relaxer lawsuits 2026 rely on these shared memories, along with photos and medical records, to tell the story. Whether a family may bring a claim depends on state law.

Symptoms and Medical Records to Discuss With Your Doctor

This article is about research, not diagnosis. But many readers are here because they or a loved one are worried about symptoms. Your doctor is the right person to talk to about your health.

Symptoms worth reporting

The National Cancer Institute advises checking with a doctor if you have any of the following, which can be signs of endometrial cancer, the most common type of uterine cancer:

• Vaginal bleeding or discharge not related to your period
• Vaginal bleeding after menopause
• Difficult or painful urination
• Pain during sex
• Pain in the pelvic area

These symptoms can have many causes, and most are not cancer. Still, they deserve a medical check, especially bleeding after menopause.

Telling your doctor about relaxer use

Your health comes first, well ahead of any questions about hair relaxer lawsuits 2026. It is fine to mention that you used chemical relaxers or straighteners, and for how long. Your doctor can note it in your history. That record may help later if you decide to ask a law firm whether you may qualify for one of the hair relaxer lawsuits 2026 claims.

Records that often matter

If you have already been diagnosed, it helps to keep copies of:

• Pathology or biopsy reports that confirm the type of cancer
• Surgery records, such as a hysterectomy report
• Imaging reports and treatment summaries
• A list of your doctors, hospitals and dates of care

You can usually request these from your providers’ patient portals or records offices. Keep them in one folder, together with your product timeline.

How Courts Use This Research in Hair Relaxer Lawsuits 2026

Scientific studies do not decide lawsuits on their own. Courts have rules about how research can be used, and those rules shape what happens in hair relaxer lawsuits 2026 and beyond.

Where the federal cases are

In February 2023, the Judicial Panel on Multidistrict Litigation combined federal hair relaxer cases into MDL No. 3060, In re: Hair Relaxer Marketing, Sales Practices, and Products Liability Litigation, before U.S. District Judge Mary M. Rowland in the Northern District of Illinois. The panel’s transfer order listed shared questions, including whether exposure to phthalates or other endocrine-disrupting chemicals causes injury to the reproductive system.

An MDL is not a class action. Each person’s case remains separate, but early steps like sharing documents and testing the science happen in one place. Some cases are also filed in state courts.

General causation and specific causation

Courts usually split the science into two questions:

• General causation: Can the products cause this type of cancer at all? Studies like the Sister Study are central here.
• Specific causation: Did the products likely contribute to this person’s cancer? This looks at the person’s own use, medical history and other risk factors.

A study can support the first question without answering the second. That is why both the research and your personal records matter in hair relaxer lawsuits 2026.

How judges screen scientific testimony

In federal court, Federal Rule of Evidence 702 governs testimony from scientific witnesses. Judges act as gatekeepers and can exclude opinions they find unreliable. Each side’s witnesses must show how they reached their conclusions from the research.

This step can take a long time in large cases like hair relaxer lawsuits 2026. Its outcome often shapes what happens next, including whether test trials move forward.

Be wary of promises

Ads about hair relaxer lawsuits 2026 sometimes mention large dollar amounts or say a settlement is coming soon. No one can promise how a case will end or what it may be worth. Court records, the judge’s orders and a participating law firm are more reliable sources than a social media post. If anyone asks you to pay upfront to join a claim, ask questions before you share personal details.

Research Terms in Plain Language

News stories and court papers about hair relaxer lawsuits 2026 often use research words that can be confusing. Here are simple explanations of some common ones.

Cohort study

A study that follows a large group of people over time and records who gets sick. The Sister Study and the Black Women’s Health Study are cohort studies.

Association

A link seen in the data between two things, such as product use and a disease. An association alone does not prove that one thing caused the other.

Hazard ratio

A number that compares how often a disease shows up in one group versus another over time. A hazard ratio of 2 means the disease appeared about twice as often in the exposed group during the study.

Confounding

When a third factor affects both the exposure and the disease, it can make a link look stronger or weaker than it really is. Researchers try to adjust for factors like age, weight and hormone use.

Recall bias

Errors that happen when people do not remember past habits accurately. It matters because most relaxer studies rely on self-reported use.

Endocrine-disrupting chemicals

Chemicals that can interfere with the body’s hormones. Phthalates and parabens are examples researchers have studied in hair products.

Statistical significance

A way of judging whether a result is likely to be more than chance. Results that are not statistically significant may still be worth studying, but they are weaker evidence on their own.

Peer review

The process in which other scientists review a study before a journal publishes it. Peer review checks the methods, but it does not mean a finding is always correct.

Understanding these terms can make it easier to follow new research as it comes out. If you have questions about how the science applies to you, a participating law firm may review your history. Filing deadlines vary by state and claim type.

Hair relaxer lawsuits 2026: frequently asked questions

How Direct2Attorney can help

If you used chemical hair relaxers or straighteners and were later diagnosed with uterine, ovarian or another cancer, a participating law firm may review whether you qualify for a hair relaxer lawsuit. Visit our hair relaxer lawsuit page to share your story. Filing deadlines vary by state and claim type.

The research on hair relaxers is still growing. Understanding what it says can help you decide your next step.

Direct2Attorney is a legal marketing and referral service, not a law firm. This article is general information, not legal advice. Submitting information does not create an attorney-client relationship.