Antiperspirants are formulated to prevent underarm sweating and wetness. Aluminum compounds temporarily plug the sweat ducts which reduces sweat on the skin surface. Antiperspirants are regulated by the FDA and are considered over-the-counter (OTC) drugs. The active ingredient must be an approved aluminum compound, and the labeling must include Drug Facts as outlined in the OTC monograph, which provides the FDA “rules” for antiperspirants.
Aluminum-free deodorants are formulated to neutralize or mask underarm odor. They do not prevent sweating or wetness. A deodorant without aluminum is considered a cosmetic because it does not contain an aluminum compound or other active ingredients. Cosmetics are not regulated by the FDA.
An antiperspirant/deodorant combats both sweat and odor in one product. These combination products are very common.
The antiperspirant component still requires an approved aluminum compound as the active ingredient. Because of this, all antiperspirant/deodorant products are considered OTC drugs and are regulated by the FDA.
The deodorant component comes from additional non-active ingredients that neutralize or mask underarm odor. Also, the effect of an antiperspirant on reducing underarm sweat and wetness has the additional effect of reducing odor.
Speculation regarding the use of aluminum in antiperspirants and the risk of breast cancer have been shown to be unfounded. The FDA, the American Cancer Society, and the National Cancer Institute have independently investigated and concluded there is no credible scientific/medical evidence linking the use of antiperspirants to breast cancer.
The main concern with using a deodorant or antiperspirant is skin irritation. For people with sensitive skin this can be a real issue. Most antiperspirants and deodorants contain fragrances or botanicals to help mask odor. Just because it says ‘fragrance-free’ doesn’t mean it is ‘free of fragrance’. Some products claiming to be fragrance-free, unscented, or hypoallergenic still contain botanicals, or other ingredients to impart a pleasant smell, that may be irritating to sensitive skin. Even if a product is labeled for sensitive skin, always check the label carefully for common chemical irritants or other ingredients that may be of concern for you.