There are some factors that research has shown are not linked to breast cancer. You may see information online or hear about these disproven or controversial risk factors, but it's important to learn the facts.
For information on known and possible breast cancer risk factors, see:
Online and social media rumors have suggested that chemicals in underarm antiperspirants are absorbed through the skin, interfere with lymph circulation, and cause toxins to build up in the breast, eventually leading to breast cancer.
Based on the available evidence (including what we know about how the body works), there is little if any reason to believe that antiperspirants increase the risk of breast cancer. For more information, see Antiperspirants and Breast Cancer Risk.
Online and social media rumors and at least one book have suggested that bras cause breast cancer by obstructing lymph flow. There is no scientific or clinical basis for this claim, and a 2014 study of more than 1,500 women found no association between wearing a bra and breast cancer risk.
Several studies have provided very strong data that neither induced abortions nor spontaneous abortions (miscarriages) have an overall effect on the risk of breast cancer. For more detailed information, see Abortion and Breast Cancer Risk.
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
American Cancer Society. Breast Cancer Facts & Figures 2019-2020. Atlanta, Ga: American Cancer Society; 2019.
Chen L, Malone KE, Li CI. Bra wearing not associated with breast cancer risk: A population-based case–control study. Cancer Epidemiol Biomarkers Prev. 2014;23(10):2181-2185.
Chlebowski RT. Factors that modify breast cancer risk in women. UpToDate. 2021. Accessed at https://www.uptodate.com/contents/factors-that-modify-breast-cancer-risk-in-women on August 30, 2021.
Last Revised: December 16, 2021
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