A 25-year longitudinal study of black women links frequent use of lye-based hair relaxers to a better risk of breast cancer.

Big idea

Frequent and long-term use of lye-based hair straightening products or relaxers may increase the danger of breast cancer in black women in comparison with more moderate use.

of Boston University Black Women's Health Study followed 59,000 self-identified African American women for greater than 25 years, sending out questionnaires every two years about latest diagnoses and aspects influencing their health.

Using these data Our own study, My team of epidemiologists and I It seems that black women who used Hair products containing lye At least seven times there was one for 15 or more years 30 percent increased risk. Of Estrogen receptor positive Breast cancer in comparison with more infrequent users.

The minimal association between hair relaxers (with or without lye) and breast cancer risk for moderate users is mostly reassuring. But the elevated risk for the heaviest users of lye-based hair products — which included about 20 percent of study participants — is concerning.

Why it matters

There is an urgent need to handle racial disparities in breast cancer.

Black women are diagnosed with breast cancer. 40% more likely to die. from the disease in comparison with white women. While systemic aspects resembling Delay in diagnosis And Poor health care Likely contributing to this disparity, they don’t appear to completely explain the survival difference between black and white women.

Black women usually tend to develop it than white women. Highly aggressive breast cancer They have a better mortality rate, but researchers don't really know why. However, scientists do know this Chemical hair relaxersMore often utilized by black women, comprises Potentially harmful ChemicalsKnown as possible carcinogens and chemicals. Endocrine disruptors, which may interfere with hormone function and increase the danger of breast cancer. In the Black Women's Health Study, 95% women Reported past or current use of those products.

This study fills a knowledge gap regarding the potential health effects of popular consumer products amongst Black women. Given these findings, women will want to watch out in regards to the forms of personal care products they select.

Which isn’t known yet.

Because the Black Women's Health Study didn’t have information on specific brands of hair relaxers, my team and I couldn’t determine which specific ingredients is perhaps most relevant to breast cancer risk. are Also, because we asked about hair relaxer use before 1997, the outcomes of this study may not apply to products available on the market today.

Although our results suggest an association between the usage of certain forms of hair relaxers and breast cancer, epidemiological studies resembling this cannot definitively prove that hair relaxers cause breast cancer. are made Additional research is required, especially on existing products.

And what research is being done?

Evidence from animals and others An empirical study Support a possible link between chemicals involved in hair relaxers and cancer development. the study On Hair comfortable use And Risk of breast cancer In people, nonetheless, conflicting results have been found, possibly resulting from differences within the forms of products used or asked about.

what's next

Thanks to the 59,000 study participants within the Black Women's Health Study, our research team continues to research the danger aspects for breast cancer and other diseases amongst Black women. By understanding the reason behind disease and learning about ways to scale back risk, society can take a step toward eliminating health disparities.

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