For the media

Can hair straighteners increase your risk of uterine cancer?

By The Health News Team | November 29, 2022
Person with half straight hair and half curly hair

A study by the U.S. National Institute of Health has found a connection between chemical hair straightening products and uterine cancer.

The data used was the result of a larger study called the Sister Study, involving more than 33,000 women and aimed at identifying risk factors for breast cancer as well as other health conditions. Participants were followed for more than 11 years and during that time, 378 women were diagnosed with uterine cancer.

The research revealed that women who frequently used chemical hair straightening products were twice as likely to develop uterine cancer than women who didn’t use them. Frequency was defined as using the products more than four times in the previous year. Nonusers of hair straighteners had more than a 1.6% chance of developing uterine cancer by age 70, while the risk for frequent users went up to over 4%.

Dr. Reema Batra, a board-certified medical oncologist affiliated with Sharp Grossmont Hospital, says uterine cancer is relatively rare. “In the general population of women, it’s not commonly diagnosed. About 50,000 women are diagnosed every year,” she says.

In comparison, approximately 264,000 cases of breast cancer are diagnosed annually. “However, the findings are interesting and definitely warrant more exploration,” she says.

About uterine cancer
The most common type of uterine cancer is endometrial cancer, which occurs when cancer cells invade the endometrium, which is the inner lining of the uterus. While the exact cause of uterine cancer is not known, Dr. Batra says certain risk factors are linked to the disease. These include:

  • Increasing age

  • Obesity

  • High blood sugar

  • Unopposed estrogen (HTN and DM2, two types of estrogen replacement therapies women might use to regulate their hormones during and after menopause)

The study did not collect information on specific brands or ingredients in hair products. However, it did note several chemicals that are found in the straighteners might increase cancer risk, including parabens, bisphenol A, metals and formaldehyde, the latter of which is a known carcinogen that can cause cancer. However, more research is needed to determine if specific chemicals are increasing risk.

Why Black women are at increased risk
Because Black women frequently use straighteners and relaxers on their hair, the findings are particularly relevant to this group. Approximately 60% of the participants who reported using straighteners in the previous year were self-identified Black women. Therefore, any adverse health effects would be greater for Black women due to higher prevalence of use.

“The takeaway is that it’s important to be aware of the things we consume or use on our bodies,” says Dr. Batra. “Whether it’s food or beauty products, it could come with potential risks that are bad for our health.”

If you choose to use a straightener, Dr. Batra says it’s important to speak with your hair stylist and ask what chemicals are present in the product you’re using. “There are now several newer products that are more natural and have less toxins,” she says.

Learn more about cancer; get the latest health and wellness news, trends and patient stories from Sharp Health News.

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