--- title: "Do Underwire Bras Cause Breast Cancer? Bra Myths Explained" description: "Do underwire bras cause breast cancer? What NHS sources say about the bra myth, why a badly fitting bra can hurt, and the breast changes worth getting checked." url: https://breastcancer-charity.org/answers/do-underwire-bras-cause-breast-cancer/ robots: noindex --- # Do Underwire Bras Cause Breast Cancer? Bra Myths Explained Myths and facts ## Quick answer No. Underwire bras have not been found to cause breast cancer, says The Royal Marsden NHS Foundation Trust. The idea that wires restrict the flow of lymph fluid in the breast and let toxins build up has no evidence behind it. Bras are not on the NHS list of risk factors, though a badly fitting bra can be uncomfortable. Source: [The Royal Marsden NHS Foundation Trust: Busting breast cancer myths](https://www.royalmarsden.nhs.uk/private-care/news-and-blogs/busting-breast-cancer-myths) **Content updated:** 22 October 2026 . Reviewed by a UK GP for World Aid Network on 22 October 2026 . [How we prepare health information](https://breastcancer-charity.org/editorial-policy/) · [Report an error](https://breastcancer-charity.org/corrections/) **How this page is sourced:** health information here comes from NHS, NICE and WHO pages, linked beside each claim. It is general information: a GP or doctor can advise on your own situation. ## Quick facts Underwire and cancer Underwire bras have not been found to cause breast cancer Source: [The Royal Marsden NHS Foundation Trust: Busting breast cancer myths](https://www.royalmarsden.nhs.uk/private-care/news-and-blogs/busting-breast-cancer-myths) The “trapped toxins” theory No evidence that bra wires restrict lymph flow and cause a build-up of toxins Source: [The Royal Marsden NHS Foundation Trust: Busting breast cancer myths](https://www.royalmarsden.nhs.uk/private-care/news-and-blogs/busting-breast-cancer-myths) On the NHS risk list? No. Bras, wired or not, are not among the causes the NHS lists Source: [NHS: Causes of breast cancer in women](https://www.nhs.uk/conditions/breast-cancer-in-women/causes-of-breast-cancer-in-women/) NHS tip for sore breasts A properly fitted bra during the day and a soft bra to sleep in Source: [NHS: Breast pain](https://www.nhs.uk/symptoms/breast-pain/) ## Key takeaways - Underwire bras have not been found to cause breast cancer. [(The Royal Marsden NHS Foundation Trust: Busting breast cancer myths)](https://www.royalmarsden.nhs.uk/private-care/news-and-blogs/busting-breast-cancer-myths) - The theory that bra wires restrict the flow of lymph fluid and trap toxins in the breast is not supported by evidence. [(The Royal Marsden NHS Foundation Trust: Busting breast cancer myths)](https://www.royalmarsden.nhs.uk/private-care/news-and-blogs/busting-breast-cancer-myths) - A bra that is too small can cause pain, discomfort or swelling where the wires dig into the skin. [(The Royal Marsden NHS Foundation Trust: Busting breast cancer myths)](https://www.royalmarsden.nhs.uk/private-care/news-and-blogs/busting-breast-cancer-myths) - One NHS hospital leaflet calls underwired bras a personal choice, as long as the wires sit flat and do not dig in. [(Gateshead Health NHS Foundation Trust: Breast pain leaflet)](https://www.gatesheadhealth.nhs.uk/resources/breast-pain/) - Whatever bra you wear, get any new lump or breast change checked by a GP or doctor. [(NHS: Symptoms of breast cancer in women)](https://www.nhs.uk/conditions/breast-cancer-in-women/symptoms-of-breast-cancer-in-women/) ## Where did the underwire bra myth come from? Some people thought that bra wires press on the breast and restrict the flow of lymphatic fluid, so that toxins build up and lead to cancer. The Royal Marsden, an NHS cancer hospital in London, says there is no evidence to support this, and that underwire bras have not been found to cause breast cancer. Bras are also missing from the NHS list of things that make breast cancer more likely. That list includes being over 50, dense breast tissue, a family history of breast or ovarian cancer, certain breast conditions and higher hormone levels. Sources: [The Royal Marsden NHS Foundation Trust: Busting breast cancer myths](https://www.royalmarsden.nhs.uk/private-care/news-and-blogs/busting-breast-cancer-myths); [NHS: Causes of breast cancer in women](https://www.nhs.uk/conditions/breast-cancer-in-women/causes-of-breast-cancer-in-women/) ## Can a badly fitting bra cause problems? It can be uncomfortable. The Royal Marsden says ill-fitting bras, especially ones that are too small, can cause pain, discomfort or swelling because the underwires dig into the skin. A bra that fits well should avoid this. Gateshead Health NHS Foundation Trust’s breast pain leaflet says underwired bras are a personal choice. It advises that the wires should sit flat and comfortably against your rib cage and chest bone, without digging in or gaping. Sources: [The Royal Marsden NHS Foundation Trust: Busting breast cancer myths](https://www.royalmarsden.nhs.uk/private-care/news-and-blogs/busting-breast-cancer-myths); [Gateshead Health NHS Foundation Trust: Breast pain leaflet](https://www.gatesheadhealth.nhs.uk/resources/breast-pain/) ## Can the right bra help with breast pain? The NHS suggests wearing a properly fitted bra during the day and a soft bra to sleep in to help ease breast pain. A leaflet from Royal United Hospitals Bath NHS Foundation Trust adds that a more supportive bra can often help, and sometimes a sports or soft bra. The NHS says breast pain by itself is unlikely to be a symptom of cancer. See a GP if the pain is not improving or painkillers are not helping. Sources: [NHS: Breast pain](https://www.nhs.uk/symptoms/breast-pain/); [Royal United Hospitals Bath NHS Foundation Trust: Breast pain (mastalgia) leaflet](https://www.ruh.nhs.uk/patients/patient_information/BRU022_Mastalgia.pdf) ## Which breast changes should you get checked? The NHS says to see a GP or doctor if you notice: - a lump or swelling in your breast, chest or armpit - a change in the skin of your breast, such as dimpling (it may look like orange peel) - a change in skin colour – on white skin it may look red, on black or brown skin it may look darker than usual - a change in the size or shape of one or both breasts - nipple discharge (if you are not pregnant or breastfeeding), which may have blood in it - a change in the shape or look of your nipple, such as it turning inwards or a rash on it Some of these symptoms, including breast lumps, are very common and can be caused by other conditions. Having them does not definitely mean you have breast cancer, but it is important to get checked. Source: [NHS: Symptoms of breast cancer in women](https://www.nhs.uk/conditions/breast-cancer-in-women/symptoms-of-breast-cancer-in-women/) ## Frequently asked questions Do tight bras cause breast cancer? Underwire bras have not been found to cause breast cancer, says The Royal Marsden NHS Foundation Trust. But bras that are too small can cause pain, discomfort or swelling because the wires dig into the skin. Wearing a bra that fits well should avoid this. Source: [The Royal Marsden NHS Foundation Trust: Busting breast cancer myths](https://www.royalmarsden.nhs.uk/private-care/news-and-blogs/busting-breast-cancer-myths) Do underwire bras block lymph drainage? This is the theory behind the myth: that bra wires restrict the flow of lymphatic fluid in the breast and let toxins build up. The Royal Marsden NHS Foundation Trust says there is no evidence to support it. Source: [The Royal Marsden NHS Foundation Trust: Busting breast cancer myths](https://www.royalmarsden.nhs.uk/private-care/news-and-blogs/busting-breast-cancer-myths) Should I wear a bra at night? If your breasts are sore, the NHS suggests a properly fitted bra during the day and a soft bra to sleep in. It also says breast pain by itself is unlikely to be a symptom of cancer, but to see a GP if the pain is not improving. Source: [NHS: Breast pain](https://www.nhs.uk/symptoms/breast-pain/) What actually makes breast cancer more likely? The NHS says you may be more likely to get breast cancer if you are over 50, have dense breast tissue, have close family who have had breast or ovarian cancer, or have certain breast conditions. Higher hormone levels and lifestyle factors such as smoking also play a part. Source: [NHS: Causes of breast cancer in women](https://www.nhs.uk/conditions/breast-cancer-in-women/causes-of-breast-cancer-in-women/) When should I see a GP about my breasts? The NHS says to see a GP if you have a lump or swelling in your breast, chest or armpit, any breast or nipple change that is not normal for you, or pain in your breast or armpit and a family history of breast or ovarian cancer. Source: [NHS: Symptoms of breast cancer in women](https://www.nhs.uk/conditions/breast-cancer-in-women/symptoms-of-breast-cancer-in-women/) ## Sources and references - [The Royal Marsden NHS Foundation Trust: Busting breast cancer myths](https://www.royalmarsden.nhs.uk/private-care/news-and-blogs/busting-breast-cancer-myths) - [NHS: Causes of breast cancer in women](https://www.nhs.uk/conditions/breast-cancer-in-women/causes-of-breast-cancer-in-women/) - [Gateshead Health NHS Foundation Trust: Breast pain leaflet](https://www.gatesheadhealth.nhs.uk/resources/breast-pain/) - [NHS: Breast pain](https://www.nhs.uk/symptoms/breast-pain/) - [Royal United Hospitals Bath NHS Foundation Trust: Breast pain (mastalgia) leaflet](https://www.ruh.nhs.uk/patients/patient_information/BRU022_Mastalgia.pdf) - [NHS: Symptoms of breast cancer in women](https://www.nhs.uk/conditions/breast-cancer-in-women/symptoms-of-breast-cancer-in-women/) This page is general information, not medical advice. A GP or doctor can advise on your own situation. Source links do not imply endorsement by the NHS or another organisation. See our [editorial policy](https://breastcancer-charity.org/editorial-policy/). ## Related reading - [Breast cancer causes and risk factors →](https://breastcancer-charity.org/about-breast-cancer/breast-cancer-causes-and-risk-factors/) - [How to check your breasts →](https://breastcancer-charity.org/about-breast-cancer/breast-cancer-self-examination/) - [Breast lumps →](https://breastcancer-charity.org/about-breast-cancer/breast-lumps/) - [Breast cancer myths →](https://breastcancer-charity.org/blog/breast-cancer-myths/) - [Does breast cancer hurt? →](https://breastcancer-charity.org/answers/does-breast-cancer-hurt/) - [Breast cyst vs fibroadenoma vs breast cancer →](https://breastcancer-charity.org/compare/breast-cyst-vs-fibroadenoma-vs-cancer/) ## More myths and facts answers - [Q Does deodorant cause breast cancer?](https://breastcancer-charity.org/answers/does-deodorant-cause-breast-cancer/) - [Q Does breast size affect breast cancer risk?](https://breastcancer-charity.org/answers/does-breast-size-affect-breast-cancer-risk/) - [Q Does caffeine cause breast cancer?](https://breastcancer-charity.org/answers/does-caffeine-cause-breast-cancer/) - [Q Can a mammogram cause cancer?](https://breastcancer-charity.org/answers/can-a-mammogram-cause-cancer/) [All answers →](https://breastcancer-charity.org/answers/)