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Hair relaxer may double the risk of womb cancer, should we be worried?

Curly and coily haired girls are either celebrating natural hair or deep into their protective styling era. However, many of us still turn to hair relaxer and other chemical straightening treatments to smooth our hair – but at what risk?

According to a study carried out in the US by the National Institutes of Health (NIH) and released in 2022, frequent use of chemical hair-straightening products may double the risk of womb cancer.

The worrying results from the study saw scientists look at 33,947 racially diverse women, aged 35 to 74, across the US for more than a decade. During that time, 378 women developed uterine cancer. They found that the rate of uterine cancer was 4.05% in women who used straightening products four or more times a year, compared to 1.64% in those who did not. That's almost twice as likely.

It was in the wake of this study that 60 lawsuits were filed in the US against makers of hair relaxer conglomerates and afro hair care brands. And now campaigners here in the UK and the US are calling for the withdrawal of chemical hair straightening products containing lye (otherwise known as sodium hydroxide or caustic soda) – the main active ingredient that breaks down the hair bonds.

“We estimated that 1.64% of women who never used hair straighteners would go on to develop uterine cancer by the age of 70, but for frequent users, that risk goes up to 4.05%,” Alexandra White, PhD, an epidemiologist at the U.S. National Institute of Environmental Health Safety (NIEHS) and the study's lead author, said in a statement. "However, it is important to put this information into context. Uterine cancer is a relatively rare type of cancer," she added.

What is uterine cancer?

Uterine cancer, also known as endometrial cancer, is a type of cancer that begins in the lining of the uterus (the endometrium). Women are typically diagnosed after menopause, although it can occur at any age. The most common symptom of uterine cancer is abnormal vaginal bleeding (especially after menopause), while other symptoms may include pelvic pain, pain during intercourse and a mass or lump in the pelvic area.

Uterine cancer is the most common gynaecological cancer in the US, with around 66,000 new cases every year, according to the Centers for Disease Control and Prevention (CDC). Even though rates are rising, particularly among Black women, it is still relatively rare.

Meanwhile, in the UK there are just under 10,000 new uterine cancer cases every year – that's 27 every day (2016-2018) – making it the fourth most common cancer for women.

How are hair relaxers linked to an increasing risk of uterine cancer?

When looking at these figures it might be 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,” as Dr White tells Allure. She then adds: "More research is needed before firm recommendations can be made."

There are other factors that may contribute to the development of uterine cancer, including having a high level of the hormone oestrogen as a result of being overweight or being sedentary, which may actually play a much larger role. More on that later.

“These findings are the first epidemiologic evidence of association between use of straightening products and uterine cancer,” White and colleagues wrote in the Journal of the National Cancer Institute. “More research is warranted to ... identify specific chemicals driving this observed association.”

“But because Black women use hair straightening or relaxer products more frequently and tend to initiate use at earlier ages than other races and ethnicities, these findings may be even more relevant for them,” Che-Jung Chang, another epidemiologist at the NIEHS said in a statement.

Any 80s, 90s and even early noughties babies raised in a Black household will be familiar with the hair images on relaxer boxes. They were the epitome of It Black Girl. The models looked polished and gorgeous and had two main things in common: they were Black and had silky smooth hair. Every advert, every TV sitcom, every billboard that featured a Black woman most likely had her sporting that same look. It was only natural that so many women wanted to emulate it as the look fitted firmly into society's westernised beauty standards.

Fast forward to now and campaigners are calling on the cosmetics company L’Oréal (one of the biggest manufacturers of lye-based hair relaxers) and other manufacturers to withdraw their hair-straightening products.

The campaign is quoting this scientific research from the US National Institutes of Health, claiming a correlation between the use of chemical hair straighteners containing lye and a higher risk of uterine cancer.

The evidence is sufficient for campaigners like UK feminist group Level Up to want to take action and more than 5,000 petition signers have asked brands to remove chemicals linked to cancer from these products. In an open letter, coordinated by Level Up, campaigners also ask L'Oréal to invest in research on the long-term use of chemical relaxers.

After GLAMOUR reached out, a L’Oréal spokesperson responded: “Our highest priority is the health, wellness and safety of all our consumers. We are confident in the safety of our products and believe the recent lawsuits filed against us in the US have no legal merit. L’Oréal upholds the highest standards of safety for all its products. Our products are subject to a rigorous scientific evaluation of their safety by experts who also ensure that we follow strictly all regulations in every market in which we operate.”

The CTPA (Cosmetic Toiletry & Perfumery Association), a highly respected body in the UK cosmetics industry, has also released a statement in relation to the study. Dr Emma Meredith, Director-General of CTPA and a pharmacist says: “Understanding relationships between potential risk factors and diseases can be difficult and this study gathered data on many different characteristics and lifestyle factors, several of which were associated with a higher risk of uterine cancer. However, the study did not gather information on which hair products were used by the women, or their ingredients, so it cannot make a link between hair straighteners and cancer.”

The bottom line

It's important to note that not all women who use hair relaxers will develop uterine cancer. The study revealed an increased risk of the cancer for women who used hair straighteners The risk of uterine cancer will also vary depending on factors such as age, family history, and overall health. Therefore, it is crucial to weigh up the potential risks and benefits of using hair relaxers on an individual basis.

To mitigate the risk of uterine cancer, there are several things you can do. Firstly, you can reduce your use of hair relaxers. So, for example, if you currently use a relaxer more than four times a year, consider limiting it to two or three times a year. “We did observe in our study that less frequent use was less strongly associated with risk, so decreasing the frequency of use may be one potential approach,” Dr. White tells Allure.

Alternatively, you could switch to less harsh alternatives such as natural hair care products, non-permanent straightening methods or heatless styling methods. You can also make lifestyle changes such as maintaining a healthy diet and exercise routine, as obesity and lack of physical activity have been linked to an increased risk of uterine cancer.

“If you look at the really big risk factors for endometrial cancer, 50 to 60 percent is directly linked to obesity and lack of physical activity,” Dr. Susan Modesitt, MD, director of the gynecologic oncology division at Emory University's Winship Cancer Institute explains to Allure.

Regular check-ups with a gynaecologist are also important for early detection of uterine cancer. There's currently no way to screen for uterine cancer but there is a possibility that uterine cancer can be picked up on a Pap smear, which your doctor should follow up with an endometrial biopsy or a transvaginal ultrasound.

So being aware of the symptoms to look out for is essential. These include vaginal spotting in postmenopausal women, while “in women who are still menstruating, it's heavier bleeding or bleeding between periods,” Dr. Ursula Matulonis, MD, the chief of the gynecologic oncology division at the Dana-Farber Cancer Institute in Boston, MA, tells Allure.

Any changes in your menstrual cycle or unusual vaginal bleeding should be reported to your doctor immediately. This is especially recommended for people with a family history of uterine cancer, who may also benefit from genetic counselling and testing to determine their individual risk.

After all, having straighter hair should never come at the expense of your health.

This article was originally published on Glamour UK.

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