Women who used chemical hair straightening products had a higher risk of uterine cancer compared to women who did not report using these products, according to a new study by the US National Institutes of Health (NIH). The researchers found no association with uterine cancer for other hair products the women used, including hair dyes, bleaches or perms.
The survey data includes 33,497 American women aged 35-74 participating in a study conducted by the National Institute of Environmental Health Sciences (NIEHS), part of the NIH, which aims, among other things, to identify risk factors for breast cancer. The women were followed for almost 11 years and during this time 378 cases of uterine cancer were diagnosed.
The earlier and more often we straighten our hair, the risk increases
The researchers found that women who reported frequent use of hair straightening products, which was defined as more than four times in the previous year, were more than twice as likely to develop uterine cancer compared to those who did not use these products. - We estimated that 1.64 per cent of women who had never used a hair straightener would develop uterine cancer by the age of 70; but for frequent users the risk increases to 4.05 per cent, - said Dr Alexandra White, head of the NIEHS Environment and Cancer Epidemiology group and lead author of the new study. - This doubling of risk is worrying, but it is important to put this information in context: uterine cancer is a relatively rare type of cancer, she added.
Research shows that uterine cancer rates in the United States are rising particularly among black women. According to a study published in the Journal of the National Cancer Institute, approximately 60 per cent of participants who reported using a hair straightener in the previous year were black women. The study did not find that the association between the use of chemical hair straightening and the incidence of uterine cancer differed by race: adverse health effects may be greater for black women due to their more frequent use. - These women tend to start using them at a younger age than other races and ethnic groups, so this information may be more relevant to them, said Dr Che-Jung Chang, a researcher in the epidemiology branch of the NIEHS.
Parabens, bisphenol A, metals and formaldehyde to blame?
This finding is in line with previous studies showing that chemical hair straightening products can increase the risk of hormone-related cancers in women.
The researchers did not collect information on the brands or ingredients of the hair products the women used. However, they note in the article that several chemicals that were found in hair straighteners (such as parabens, bisphenol A, metals and formaldehyde) may contribute to the observed increased risk of uterine cancer. The risk of exposure to chemicals when using hair products may be greater than for other personal care products due to increased absorption by the scalp, which may be compromised by burns or damage just caused by trying to straighten.
- To our knowledge, this is the first epidemiological study to examine the association between hair straightener use and uterine cancer, said White. - Further research is needed to confirm these findings in different populations, to determine whether hair products contribute to health disparities in uterine cancer and to identify specific chemicals that may increase cancer risk in women, she concluded.
Her team previously found that permanent hair dye and chemical straightening can increase the risk of breast and ovarian cancer.
Uterine cancer in Poland
Cervical cancer is detected in Poland most frequently in women over 60 years of age - in 46 patients per 100,000 women. According to the National Cancer Registry, between 1999 and 2016, the incidence of cervical cancer in Poland fell by 26.5 per cent, while the number of deaths from cervical cancer decreased by 15.5 per cent.
The main factors influencing the occurrence of cervical cancer are:
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chronic infection with human papillomavirus HPV 16 and 18 or other oncogenic types
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early onset of sexual intercourse
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large number of sexual partners or unfaithful partner
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high number of births
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age (the incidence increases with age)
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many years of smoking
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history of cervical intraepithelial neoplasia (CIN).
Probable causes:
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long-term use of hormonal contraceptives
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poor diet, rich in red meat, processed meat, fatty sauces and low in olive oil
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HIV infection
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sexually transmitted genital infections other than HPV (e.g. chlamydia, cysticercosis, herpes virus HSV-2).
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immunosuppressed states - immunosuppression in connection with organ transplantation.
Endometrial cancer
Endometrial cancer occurs primarily after the menopause, with 25 per cent of cases occurring in premenopausal women. The endometrium is the epithelium lining the endometrial cavity, which is located in the body of the uterus. The risk factors for endometrial cancer are different from cervical cancer. In endometrial cancer, these are: age over 40, infertility or low fertility, metabolic disorders (e.g. obesity and diabetes), hormonal disorders, non-ovulatory cycles or genetic factors.
In the case of cervical cancer, HPV is the main cause, endometrial cancer is more multi-causal: endocrine and metabolic disorders are important.
Uterine cancers can be easily detected even in their early stages. If diagnosed early, they are fully curable. This is why it is so important for women to have regular cytology.
Source: cowzdrowiu.pl