Antiperspirants
Because antiperspirants and deodorants are applied near the breast and contain potentially harmful ingredients (e.g., aluminum-based compounds), some have suggested that there is a link between them and breast cancer. While some studies have focused on the relation between aluminum-based compounds and breast cancer, others have shifted their attention to parabens (preservatives found in those products) as they are thought to mimic the activity of estrogen, which is known to increase the risk of breast cancer. However, studies conducted to date have shown that there is no strong link between breast cancer and antiperspirants.