NAIROBI, Kenya Jan 28 – A study by Brazilian medical researchers has found that women who wear tight bras for many hours a day may face a significantly higher risk of developing breast cancer, adding a new dimension to discussions around lifestyle-related risk factors for the disease.
The research, led by Dr Salete da Silva Rios of the Department of Gynaecology and Obstetrics at the School of Medicine in Brazil, suggests that both the tightness of a bra and the number of hours it is worn daily could be linked to increased breast cancer risk.
Breast cancer remains the most common cancer affecting women worldwide. While genetics, age, reproductive history and lifestyle factors such as diet and physical activity are well-known contributors, scientists say the exact causes are still not fully understood.
The researchers conducted a case-control study involving 304 women, half of whom had been diagnosed with breast cancer, while the other half had no history of the disease.
Participants were asked about known breast cancer risk factors as well as their bra-wearing habits. Researchers physically measured the women’s chest circumference and compared it with the bra band size to determine how tight the bra was referred to in the study as the ‘stretch percentage.’
This stretch percentage was then multiplied by the number of hours per day the bra was worn, creating a combined measure of pressure and duration.
Using statistical analysis, the researchers found that women with a high tightness-and-hours coefficient had a 2.27 times higher likelihood of having breast cancer compared to those who wore looser bras or wore bras for fewer hours.
The association was observed among both pre-menopausal and post-menopausal women, suggesting that age and hormonal status did not eliminate the potential risk.
What Could Be the Link?
Although the study did not investigate biological mechanisms in detail, some medical experts believe that prolonged pressure from tight clothing may interfere with lymphatic drainage in breast tissue, potentially affecting the body’s ability to remove toxins and waste products.
However, scientists caution that this study shows an association, not direct causation adding that bra use should not be seen as the sole or primary cause of the illness.
“Breast cancer is a complex disease with multiple contributing factors,” the researchers noted.
The researchers did not advise women to stop wearing bras altogether, but suggested that women may consider choosing well-fitted, non-restrictive bras and avoiding prolonged use of very tight undergarments, especially at home or while sleeping.
Some earlier studies have suggested that women who rarely or never wear bras may have a lower risk of breast cancer, but medical experts say more large-scale, long-term studies are needed before firm public health recommendations can be made.
Cancer specialists not involved in the study warn against panic or drastic lifestyle changes based on a single study.
Despite its limitations, the research is among the first to scientifically examine how both tightness and duration of bra use together may relate to breast cancer risk.
The findings may encourage further research into everyday habits that could influence long-term health, particularly in low- and middle-income countries where awareness and screening rates remain low.
Breast cancer is the leading cancer in Kenya, especially among women, with high incidence (around 7,000 new cases yearly) and mortality due to late diagnosis (often Stage III/IV) and barriers to care, affecting younger women (35-50) compared to Western nations.
Key challenges include limited screening, treatment access, and high costs, prompting government partnerships and initiatives to improve awareness, diagnosis, and affordable care through with focus on early detection and holistic management.
