Photography by Paul Buceta

Up there with birthdays or a brand new pair of sneakers, there are few better feelings than a solid sweat session. Whether you’re glistening from a 5k run or dripping after a killer weight room circuit, a sweaty glow can feel sexy and strong, and even be coveted confirmation that you left it all on the floor (literally).

Of course, sweating isn’t always a welcomed accessory, particularly when it shows up in the form of embarrassing pit stains or accompanied by an unpleasant aroma—a problem that plagues some of us more than others.

The complexity of this bodily function made us wonder exactly how much sweat is too much (or too little) when we exercise, and can we control the amount we perspire outside of the gym? And while we’re on the subject: is sweat really your “fat crying”?

For these answers and more, keep reading. We wring out the details of this misunderstood process of thermoregulation, just in time for the sweatiest season.

What is sweat, really? 

Sweat involves the release of fluid from the sweat glands of the skin. It’s designed to regulate body temperature, cooling you down when your body temp gets too high, be it from pounding the pavement, a hot day, stress, eating spicy food, even illness and fighting infection. As the fluid evaporates, you cool down. 

While a popular misconception is that sweat automatically comes with germs and a stench, sweat isn’t actually unhygienic or naturally smelly—it’s 99 percent water, and the rest is salt, minerals, chemicals such as ammonia, and fat (sometimes). So the “sweat is your fat crying” cliché isn’t entirely untrue, but more on that later.

In addition to acting as a thermoregulator, sweat has other small benefits. For one, it contains an antibiotic chemical called dermcidin, which defends your body against bugs and bacteria (very handy when you spend a lot of time in the gym). What’s more, new research from the American Physiology Society suggests that perspiration can even help protect your skin’s blood vessels from sun damage. Although we wouldn’t recommend ditching the SPF  just yet.

Give two sweats

There are actually two types of sweat glands. While both tend to kick in simultaneously, the type of sweat they produce are very different and perform different functions.

Producing a clear, odourless fluid, eccrine glands are the most common, occurring all over the body and doing the most work to keep us cool.

But for those times you catch of whiff of yourself and have to reach for the deodorant, you can blame the apocrine glands. Not only do they produce more sweat than their counterparts, the fluid they release also contains an oily substance which breaks down and produces an odor. 

“Concentrated in the hair follicles of your scalp, armpits, and groin, the smelly kind of sweat happens when the apocrine glands release the fatty-secretions which then mixes with bacteria on the skin,” says Australian-based dermal therapist Dr Giulia D’Anna.

And here’s a fun fact: in mammals, apocrine glands produce pheromones that help to attract a mate, which might explain why they are most active in humans during sex. Lucky us. 

How much is too much?

While you may have to wring out your soaked sports bra after spin class, the woman next to you may go straight to brunch without so much as smudged mascara. So what gives?

Most people have anywhere from 2-4 million sweat glands, but how much sweat each produces comes down to the person and their genetics. Gender, the weather, and age also play a part, as will fitness level. “There have been several studies that show fitter people sweat sooner and more efficiently than less fit people,” says DR. D’Anna. “So sweating can actually be a sign of your body functioning optimally.”

But determining how much profuse perspiration is too much, is easier said than done.

During exercise, the average person will sweat between 27–47 oz per hour, depending on the activity. One way to roughly measure your own sweat rate is to weigh yourself before and after an hour on the treadmill (just don’t drink any fluids or go to the bathroom). Each pound you lose on the scales equals 15.4 ounces of sweat you’ve lost.

If you suspect you might be an excessive sweater, ask yourself if it’s enough to derail your daily life, happiness, or confidence. “Sweat quantity is very difficult to measure,” says Dr D’Anna. “It usually comes down to the impact sweating has on your life.”

Incidents of excessive sweating, especially when you get nervous or when the temps start to rise, could be a symptom of hyperhidrosis, a condition caused by overactive sweat glands, leaving you up to 10 times sweatier in response to emotions or temperature changes. Hyperhidrosis tends to stick to one or two areas of the body, such as your feet or underarms, and while there’s no denying it can be embarrassing, it’s not harmful to your health.

Other reasons you might sweat more than most include hormonal fluctuations during your period or menopause. Nerve damage, an overactive thyroid, low blood sugar, and even certain medications can also cause excessive sweating, so if you do notice an unusual spike in your sweat status, check with your doc to find out what’s going on.

Sweat solutions

While you can’t control your age or DNA, there are steps you can take that may help control your perspiration and odor.


Some deodorants contain aluminium chloride, which clog the sweat glands and can help keep stronger smelling sweat sessions at bay. Even better news is that there isn’t any current evidence that the clinical-strength stuff is cancer-causing, despite initial fears. 

Laser hair removal

It might sound strange, but laser hair removal won’t just save you time and dollars on monthly waxes. It can also help to control sweaty body odors. By removing the hair, you also pluck away at the places where bacteria (and smells) breed. Win, win.

Stress less

Spend some time getting zen! Yoga or meditation can help calm the nerves and control emotional stressing when your fight or flight responses kick in.


Sweating that’s really bad and diagnosed as having more sinister causes by your doctor can potentially be treated with Botox. Bigger doses are used at the armpits, while tiny doses have been used more recently to reduce face and scalp sweat.

Sweat Myths Busted

Dr. D’Anna sets the record straight, busting some of the most common perspiration misconceptions:

Myth 1: Sweat is yellow.

“Sweat itself is clear. It is the breakdown of the fat within sweat by bacteria that causes the yellowing effect.”

Myth 2: Sweating = Weight Loss

“Sure, sweat will cause your body weight to fluctuate, but this isn’t fat being lost—just water! As soon as you replenish that water, your body weight will return right back to where you started.”

Myth 3: Sweating causes breakouts.

“To have a breakout, you need to have dead skin that blocks the oil glands, as well as acne producing bacteria in your skin. That said, it’s important to wear sports clothing that allows the sweat to escape, so you don’t get infections caused by sweat building up and keeping the skin hot and moist for long periods of time.”

Myth 4: Sweat is a sure sign you’re detoxing.

“Sweat is water, some salts or electrolytes, and some fat or oils. Little else is lost in the process of sweating. The liver and kidneys are responsible for toxin release.”