Deodorants are formulated to eliminate armpit odor but not perspiration. They’re typically alcohol-based. When applied, they turn your skin acidic, which makes it less attractive to bacteria. Deodorants also commonly contain perfume to mask odor.The aluminum-based compounds in antiperspirants — their active ingredients — keep sweat from getting to the surface of the skin by blocking the sweat glands. There’s a concern that if the skin absorbs these aluminum compounds, they can affect the estrogen receptors of breast cells.While there are rumors linking antiperspirants to cancer, research suggests that antiperspirants don’t cause cancer. However, studies also recommend that further research is needed to study the potential link between breast cancer and antiperspirants.