The Science Behind Sweat (And Why We Smell)

We love sweating at aSweatLife, and there are a few good reasons why. It’s good for you — when paired with exercise it means you’re working hard, getting stronger and burning calories. But there is one downside to a sweaty life: you don’t smell as hot as you may feel.

I’ll never forget the first day in my youth that I became aware of my newfound teen spirit. It was a warm spring day in fifth grade and my teacher, Ms. Gold, told the class, “If anyone hasn’t already started wearing deodorant every day, you need to start. You guys stink!”

From then on I wouldn’t go anywhere without first applying deodorant, but I never really bothered to learn about why exactly sweat smells. So recently I did what any sensible person with a question does in this day and age: I Googled it – and found everything one would want to know (and more) about the science of perspiration.

Science Behind Sweat


Why we sweat 

As we all know, sweating can occur when you exercise and when your body temperature is too high, but it can also happen when you’re nervous, anxious or feeling stressed out.

Sweat is the body’s self-cooling mechanism. When body temperature rises, sweat — which is composed of mainly water and salt — is secreted and cools your skin as it evaporates, according to the Mayo Clinic.


The science of body odor

The body has two main types of sweat glands that produce very different types of sweat, according to the Mayo Clinic. Both types are odorless, but can create a bad smell when combined with normal bacteria on your skin.

Eccrine glands are located over most of you body and excrete sweat directly onto the surface of the skin. The other type of gland, called apocrine glands, develops in areas that have a lot of hair follicles, such as your armpits and groin. The sweat that comes out of these glands empties into the hair follicles and then open onto the surface of the skin.


How to not stink

One can take very simple measures to ensure his or her BO is under control. First, practice good hygiene. While our skin always has some bacteria on it, making sure your body is clean will prevent excessive bacteria from mixing with sweat and producing an unpleasant aroma. Also, antiperspirants, which contain aluminum-based compounds, help reduce sweating by temporarily blocking sweat pores, thereby decreasing the amount of perspiration that reaches your skin.

The other topical solution is deodorant. Regular deodorant — without antiperspirant — can eliminate the odor caused by sweat but doesn’t actually prevent you from sweating. Deodorant is usually alcohol based, which makes your skin acidic and a less welcoming host to bacteria. It often contains perfumes to mask the odor, too.

Individuals for whom regular antiperspirants don’t work, a physician might prescribe a stronger form that contains aluminum chloride. However, some people’s skin might become irritated by this, according to Mayo Clinic.

When it comes to selecting the right deodorant or antiperspirant – or really, what it means to put anything on your skin – we did some digging on our own. We don’t often think about what we put on our bodies in the same way we think about what we put into them, but the verdict is out about the potential negative effects of certain antiperspirants and deodorants, and many companies are working to create products that work without the health concerns.


When you should see a doctor 

Sweating is healthy and normal, but certain symptoms could be a sign of trouble, so it’s good to know what they are. Mayo Clinic says go see your doctor if you suddenly begin to sweat much more or less than usual, if excessive sweating hinders your daily routine, if you experience night sweats and if you notice a change in your body odor.

Fitness Trends Move

About Tamara Rosin

Tamara Rosin is a native Chicagoan but a Wisconsin Badger at heart with a degree in English literature and creative writing. In addition to her six years practicing yoga, Tamara loves biking, running outdoors and trying out different group workout classes. By day, Tamara is a writer/reporter for a healthcare publication. In her spare time, you can find her cooking, reading, or upside down in a headstand.