Composite: The Guardian/Getty Images View image in fullscreen Composite: The Guardian/Getty Images Call the doctor Well actually Is it unhealthy to suppress sweat? Sweat has important functions, including cooling you down when it’s hot outside. Here’s what science says about using antiperspirants and deodorants
Prefer the Guardian on Google Jump to What’s the purpose of sweat? Are antiperspirants and deodorants the same thing? Does blocking sweat in your armpits interfere with cooling? Should I use a whole-body deodorant? What if I sweat excessively? Is my usual deodorant routine OK? Every day, 5 billion people around the world reach for deodorant. Many of us assume that managing, modifying and hiding sweat is an absolute necessity – and not just in your armpits.
Routine underarm antiperspirant and deodorant use are unlikely to cause harm. But do you know what sweat is actually for, and what these products actually do?
Sweating to cool down is a genuine superpower: a well-trained human can shed nearly 4 liters an hour , keeping the body functional in heat that would incapacitate most other animals.
Sweat also has a social dimension. The odor that rises from your body – not the sharp armpit kind, but the ambient chemistry that makes you recognizable to your loved ones – results from compounds circulating in your blood, the output of your oil glands, and the unique microbial ecosystem living on your skin. Siblings can identify each other by smell and the scent of someone you love can surface a memory faster than any other sense.
No, and the difference matters more than most people realize.
Antiperspirants physically block your sweat ducts using aluminum-based compounds, which form a temporary gel plug that prevents sweat from getting through. Because they alter how a body part functions, the US Food and Drug Administration classifies them as over-the-counter drugs . This plug continues to move out of the duct over time, which is why you need to reapply periodically.
Deodorants target sweat once it’s already on your skin, using fragrances, acids that make the skin’s surface less hospitable to odor-causing bacteria, or compounds that chemically neutralize smelly molecules. In the US, they’re regulated as cosmetics, not drugs, which means companies aren’t required to prove they’re safe or effective.
The claim that antiperspirant aluminum causes breast cancer or Alzheimer’s disease has been extensively studied and consistently disproven .
Not in any meaningful way. Eccrine glands, which are responsible for cooling you down, cover almost your whole body.
The apocrine glands in your armpits and groin produce a thicker, waxier fluid that certain bacteria love to eat; those bacteria produce what we call body odor as they digest it. Blocking a few sweat glands in an area not primarily responsible for temperature regulation won’t compromise your ability to stay cool.
If you’re considering whole-body products, it’s worth pausing to ask what problem you’re actually trying to solve. The eccrine sweat covering the rest of your body is largely inoffensive; it doesn’t give bacteria much to work with. If you’re cleaning your body regularly, there is likely no genuine hygiene problem to solve on, say, your shins or your forearms.
Certain foods and medications can temporarily affect the odor of your eccrine sweat , and certain medical conditions can cause a strong unpleasant odor in a range of body sites. But for most people, the ambient smell o…