Studies connect uterine cancer with hair relaxer use.
When you buy a beauty product, it’s natural to assume it’s safe to use. But unlike other countries’ regulatory agencies, the U.S. Food & Drug Administration is not required to approve cosmetic products and ingredients, other than color additives, before they hit the market. This system has led to the FDA’s restricting or prohibiting only 11 ingredients harmful to humans in cosmetics. Contrast that with the European Union’s European Chemicals Agency that has banned more than 2,500 ingredients.
Chemical hair relaxers and straightening treatments, often marketed to Black women and children, fall into the basket of products with toxic ingredients that have gone unchecked. Recent studies link these products containing harmful substances, such as parabens and formaldehyde, to uterine cancer, the most common gynecologic cancer with two types: endometrial, which is more common, and the rarer uterine sarcoma.
“It is estimated that over 66,000 cases were diagnosed last year in the U.S.,” says Dr. Michelle Glasgow, gynecologic oncologist at Northside Hospital. “Rates of this cancer are going up, and there’s a growing body of research that demonstrates increased mortality rates in black women when compared with other races.”
In 2022, the National Institutes of Health published a report based on data from 33,497 U.S. women ages 35-74 in the Sister Study, a long-term attempt to identify risk factors for breast cancer and other health conditions. It found women who used chemical hair-straightening products were at higher risk for uterine cancer. Other products, such as hair dyes, bleach or perms, showed no correlation to the disease.
Boston University’s Black Women’s Health Study correlates with the Sister Study. This research, released last October included data from nearly 45,000 women who were followed for up to 22 years. Compared to women who never or rarely used hair relaxers, postmenopausal Black women who had used them more than twice a year or for more than five years had a greater than 50% increased risk of uterine cancer.
“While these studies show statistically significant findings that are definitely worth paying attention to, there needs to be a lot more research done,” Glasgow says. “I don’t think the risk of endometrial cancer attributed to hair relaxers can compare with obesity, which is the number one risk factor. The majority of endometrial cancers are related to an imbalance of estrogen in the body. Women who are obese have higher circulating levels of estrogen.”
Last October, the FDA said it would propose a ban on formaldehyde in hair relaxers and straighteners that has yet to happen. This ingredient, not permitted in cosmetics in the EU, is considered an “endocrine disrupting chemical.” According to the National Institute of Environmental Health Sciences, endocrine disrupters are chemicals that may interfere with the body’s hormones.
Just because someone has relaxed their hair at some point doesn’t mean they will end up with uterine cancer. But it’s worth knowing—and studying—what’s in your beauty products to make more informed decisions.
SISTER STUDY
sisterstudy.niehs.nih.gov
BOSTON UNIVERSITY CHOBANIAN & AVEDISIAN SCHOOL OF MEDICINE
bumc.bu.edu/camed/2023/10/11/
