How do antiperspirants keep you from sweating?

Is It Really Possible to Prevent Sweating?

No, and you wouldn't want to, either. Perspiration is a natural body function, regulated by your autonomic nervous system, which helps the body regulate your temperature by releasing a fluid made up of water, sodium and other substances, which evaporates to cool you [sources: Medline Plus, MIT School of Engineering]. Sweating is so important to your body that it has about 2 to 5 million sweat glands all over its surface, which pump out several liters of perspiration each day [source: Moninger].

Instead of shutting down the perspiration process entirely, what antiperspirants aim to do is control it in certain areas — like your armpits and groin — that are especially prone to be stinky. These areas are equipped with a special type of sweat gland called apocrine glands, which form around hair follicles [sources: Hansen, Williams and Schmitt]. The apocrine glands kick into gear during puberty and are stimulated by stress or excitement as well as heat [source: Grossman].

The yucky smell that we associate with underarm perspiration actually is caused not by the sweat itself, but by bacteria and other microorganisms. They feed on the perspiration and produce waste byproducts such as trans-3-methyl-2-hexenoic acid, which cause the distinctive odor we all abhor [source: Everts]. The armpits, which are covered most of the time, are a great medium to grow those microbes [source: Ramirez].

Since the late 19th century, when chemists first started tackling the problem of body odor, there have been two primary solutions. One is to mask the stinky smell with a more pleasant aroma. The other is to use chemicals to actually inhibit the release of sweat from our skin's pores, to starve those stink-producing bacteria of food. In the next section, we'll explain how that works.