National Institutes of Health, 11-year follow-up and analysis of more than 30,000 people
Women who frequently used straight hair perm drugs were more than twice as likely to develop uterine cancer as women who did not.
The results of a study conducted by the National Institutes of Health (NIH), including 33,497 women aged 35 to 74 years, followed for regarding 11 years. These women participated in the ‘Risk Factors for Breast Cancer and Other Health Conditions’ study led by the National Institutes of Environmental Health Sciences (NIEHS) under the National Institutes of Health (NIH). During the follow-up period, 378 of the participants were diagnosed with cervical cancer.
The study found that women who frequently used hair straightening drugs (chemical hair straightening products) had an approximately 2.5 times higher risk of uterine cancer than women who did not. Corresponding author of the study, NIH Alexandra White, Ph.D., said: “It was estimated that 1.64% of women who did not use straight hair perm drugs would develop uterine cancer by age 70, whereas up to 4.05% of women who frequently use straight hair perm drugs would develop uterine cancer. “It turned out to be a risk,” he said. Frequent use of straight perm drugs was defined as more than 4 uses in the previous year. “This is the first epidemiological study to investigate the association between hair straightening drugs and cervical cancer risk,” White added.
The researchers found no association with uterine cancer in other hair products they said were used by women, including hair dye, bleach, highlighters, or perms. Cervical cancer accounts for regarding 3% of all new cancer cases, but 65,950 new cases were diagnosed in 2022. Also, regarding 60% of participants who reported using hair straightening drugs last year were black women. Black women use hair straighteners or relaxers more often and tend to start using them earlier than other races and ethnicities.
“Several chemicals found in hair straightening drugs (parabens, bisphenol A, metals and formaldehyde) may increase the risk of cervical cancer,” the researchers said. The use of straighteners with hair products can be far more dangerous than other personal care products as the chemicals are absorbed much more through the scalp. It can also lead to aggravation of burns and lesions caused by straighteners. Previously, the NIH research team found that permanent hair dyes and straighteners may increase the risk of breast and ovarian cancer.
The results of this study (Use of Straighteners and Other Hair Products and Incident Uterine Cancer) were published in the ≪Journal of the National Cancer Institute≫ and introduced by the American health and medical media ‘MedicalXpress’.
