Health / Expert Advice

Why Does My Sweat Change?

Most of the time, it's totally normal.

If your soaking-wet mat is any indication of your effort during a workout (have you tried a workout from Aaptiv?), then you’re definitely killing it. For most people, sweat is associated with an intense fitness session or hot and humid temperatures. But there are many different types of sweat, all of which give you a glimpse into what’s happening in your body.

As NYC-based Certified Personal Trainer Cary Raffle explains, people experience different kinds of sweat for a variety of reasons that are often misunderstood. “Some sweat is part of the body’s cooling system; some sweat is a reaction to stress. Exercise produces both heat and stress, so it is natural that we experience both types of sweat when we work out,” he continues. But the way you sweat during a workout may be different than the way you sweat before a big presentation which may be different than the way you sweat in your sleep. And it’s all perfectly normal. The way you sweat can also change over time and when you travel through various environments. Here, we break down anything and everything you need to know about the different kinds of sweat.

So, what happens when you sweat?

Sure, it pools on your back. Drips from your brow. Sometimes seeps through your tank top. But board-certified cardiologist Dr. Luiza Petre explains what’s happening underneath the hood, so to speak. “Sweating is the mechanism through which the body regulates its own temperature,” she says.

There are two main types of sweat glands, both controlled by the nervous system, she continues. The eccrine glands are all over your body and directly open to your skin. Dr. Petre says they produce mostly water and salt and respond to temperature changes. Naturally, this is called water sweat, and the evaporation process regulates the heat of your skin. The apocrine glands open in the hair follicles and are concentrated mostly in your armpits and groin, Dr. Petre explains. These areas secrete a milk-like fluid called scent sweat, and they respond to emotional stress—both good and bad.

What is sweat made of?

Dr. Petre says the main component of sweat is water, followed by salt, potassium, and other waste products. This is why so many folks turn to hot yoga or other high-temperature workouts for a cleansing experience. The intense heat causes a release of any buildup the body is harboring. The ability to sweat may not be the cleanest of bodily functions, but it does indicate that you’re taking solid care of yourself. “Evaporating the sweat is the way the body cools down in temperature. It’s initially odorless, but in contact with skin bacteria, sweat develops an unpleasant smell similar to an onion,” Dr. Petre notes. “Healthy sweating reflects good nervous system function.”

What are the different types of sweat?

Not all sweating is caused by an intense boxing round or a trip to the Caribbean. The body goes through all sorts of sweating practices.

Direct Heat or Physical Activity Sweating

When this happens, your skin gets warmer in reaction to the effort you’re putting in or the sunshine you’re bathing in. Dr. Petre says you’ll feel the heat radiating off your body, and your skin could sweat all over or turn red.

Emotional Sweating

This response can happen when you’re scared or overwhelmed or you experience a surge of feelings. Dr. Petre says your skin will feel cold and perhaps turn pale as your blood vessels constrict. You may notice this feeling in your palms before an interview or a first date you’re excited about. It can also happen when your blood sugar or blood pressure is on the lower side as a signal to eat something stat.

Night Sweats

There’s no real rhyme or reason why some people experience night sweats and others don’t, but certain conditions do make them more likely. These include night terrors or other sleeping problems as well as certain medical ailments, such as cancer, or infections, such as a cold, Dr. Petre notes. You’ll know you’re having a night sweat if you wake up in the morning—or the twilight hours—with a wet back.

Hot Flashes

Most common for women during menopause or pregnancy, a hot flash is a brief episode of sweat triggered by hormonal changes, Dr. Petre explains. Some women also experience a rosy flush.

Dr. Petre says your doctor may tell you other interesting facts about sweating, including the fact that women have a higher number of sweat glands, but men’s sweat glands are more active. There is also a genetic component of sweating predisposition—meaning if Mom and Dad perspire heavily, you probably will, too. Generally speaking, if you’re sweating, you’re in good health. But you know your body best, and if something feels off, it’s worth a visit to a trusted physician to express your concerns.

Expert Advice Health


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