A 2025 study published in the Journal of the National Cancer Institute has highlighted an important issue: it found that women who often use chemical straighteners have a higher risk of uterine cancer compared to those who do not use them, with a risk increase of 80%. Frequent users, who apply these products more than four times a year, have even higher rates of cancer.
Statistically, this means that frequent users face a lifetime risk of 4.05%, according to a study published in the journal World Psychiatry. By comparison, those who never use chemical straighteners face a risk of only 1.64%, according to the National Institutes of Health. Why is this important? The numbers may seem small, but even a slight increase in risk can have a material impact on health. This is especially true in a situation where other health risks, like obesity, diabetes, and delayed childbearing, are increasing in India.
"After spending years in and out of clinics and talking to patients about their health choices, I've noticed that some topics really resonate with many women. We often talk about diets, exercise, and regular check-ups, but we don't discuss hair products enough. Recent studies show a link between using chemical hair straighteners often and a higher risk of uterine (endometrial) cancer. This is especially important in countries like India, where these treatments are very popular and deserve serious attention," Dr Kasturi Baruah, Oncologist and Cancer Physician, tells Health Shots.
Harmful effects of chemical hair treatments
The danger often comes from the chemicals used. "Many hair straighteners contain formaldehyde and other toxic substances, such as parabens, phthalates, and heavy metals", says Dr Baruah. These chemicals can disrupt our hormones. The International Agency for Research on Cancer (IARC) classifies formaldehyde as a known cancer-causing agent. The US FDA has also warned about the risks associated with hair treatments.
When you enjoy a day at the salon, you may breathe in a mix of chemicals. "Many people around the world, especially in countries like India, are exposed to these chemicals due to the growing popularity of hair treatments like keratin and chemical straightening", says the cancer physician. As more people visit salons, it’s important to be aware of this issue.
"I've observed a worrying trend in discussions with peers and patients: the number of endometrial cancer cases in India is increasing. Although the rates are still lower than in many Western countries, they are rising quickly," says the oncologist. This rise is related to higher obesity rates and more cases of diabetes. As lifestyle changes continue and risk factors become more common, we must take every slight increase in a woman's risk seriously.
How to reduce cancer risk
- Minimise frequency of chemical-laden products: Instead of using chemical straighteners regularly, reserve them for special occasions. You can achieve straight hair with many ways that don’t use chemicals.
- Choose wisely: If you choose to use these products, select those free of formaldehyde. "Make it a habit to check labels and ask your stylist about the ingredients they use", says the doctor. It’s also important to visit a well-ventilated salon as reduced chemical exposure is better for your health.
- Weight management: Being overweight and having diabetes are significant factors that can lead to uterine cancer, says the expert. Maintaining a healthy weight and eating a balanced diet should be a top priority.
- Be proactive: Get regular check-ups and monitor your body. If you notice unusual bleeding or other concerning symptoms, contact a physician immediately.
- Keep track: If you see a clinician, be honest about your use of chemical straighteners and other beauty products. This information can help you better understand your overall risk.
(Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.)