Abstract/Summary

On the basis that aluminium-based antiperspirant salts are designed to block apocrine sweat ducts of the axilla, and that breast cysts result from blocked breast ducts in the adjacent region of the body, it has been proposed that breast cysts may arise from antiperspirant use if sufficient aluminium is absorbed into breast tissues over long-term usage. This review collates evidence that aluminium can be absorbed from dermal application of antiperspirant salts and describes studies measuring levels of aluminium in breast tissues, including in breast cyst fluids. It is notable that breast cysts, as for breast cancers, start most frequently in the upper outer quadrant of the breast, which is the region closest to the site of underarm antiperspirant application. Mechanistic evidence is reviewed for a link between aluminium levels in breast tissue, cyst formation and development of breast cancer. If excessive use of antiperspirant is a cause of breast cysts, then reduction or cessation of use could provide a preventative or even treatment strategy. Furthermore, if cyst formation from antiperspirant use is an indicator of increased risk for breast cancer, then reduction in use of antiperspirant could also provide a strategy for reducing breast cancer risk.