Antiperspirants work by reducing sweat, while deodorants work by increasing the skins acidity to prevent body odor. The active ingredient in antiperspirants is usually aluminum-based compounds, which temporarily block sweat pores and reduce the amount of perspiration that reaches the skin. Aluminum salts are the most widely used active antiperspirant ingredient because they effectively plug up sweat ducts to temporarily stop the flow of moisture to the skin. Other ingredients in antiperspirants include emollient oils, which keep the product from flaking once it dries on your skin, and fragrances, which are often used to mask body odor. Most major brands of antiperspirants are paraben-free these days, though the preservative is still found in some products such as makeup, moisturizers, shaving products, and hair products. While there are rumors linking antiperspirants to cancer, research suggests that antiperspirants dont cause cancer. However, studies also recommend that further research is needed to study the potential link between breast cancer and antiperspirants.