Perspiration 101: Your sweatiest questions, answered.

Sweat is a natural, necessary part of being a human being. It can also make us stinky and self-conscious, especially if we’re heavy sweaters or anxiety sweaters. Staying naturally dry may seem advantageous, but not sweating enough can actually be more dangerous than sweating too much.

Where do you fall on the sweatiness spectrum? Are you a super-sweater or dry as a desert? There are people who don’t sweat much and there are people who sweat like it’s their job. One woman’s mother doesn’t even glow, much less perspire, yet she herself sweats like a soaker hose. Of course it’s perfectly normal to sweat a little or a lot. Here’s everything you need to know:  

What are the factors that generally determine how much you sweat?

Size. Smaller people generate less heat because they have less body mass to move. They also have a smaller physical surface area to cool. That translates into both sweating less and requiring less sweat to cool off. Logically, larger people generate more heat, have more surface area to cool, and therefore require a bit more perspiration to cool down. 

Age. You may have already noticed this: we become less able to easily tolerate heat as we age. Research has shown that some sweat glands, especially those under the arms, shrink and become less prolific as we age. They also become less sensitive, meaning they may not ‘notice’ that it’s gotten hot enough to sweat. They also go a little bonkers for women during menopause thanks to hormone surges, but hot flashes and night sweats are a whole other story, which you can read here. (https://integrisok.com/resources/on-your-health/2018/september/hot-flash-news-flash )

Muscle mass. Muscle mass produces more heat than fat. So even if two people have the same body weight and are similar in size, their sweat rate will differ based on their percentage of muscle mass with the more muscular people sweating more than those with a higher fat-to-muscle ratio.    

Health status/conditions. Health conditions and life stages can impact how much you sweat. Colds, flu and even mental health conditions such as anxiety and depression can impact how much you sweat. Hormone fluctuations in particular are often linked with an increase in internal body temperature. (Just ask any perimenopausal, menopausal or pregnant woman!)

Fitness. People who are very fit sweat more than their less-fit counterparts. But if fit people and less-fit people are performing the same task, the less-fit person will sweat more because they have to expend more energy to perform the same task.

Are there different kinds of perspiration? 

Yes, because we have three kinds of sweat glands: eccrine, apocrine and apoeccrine. Eccrine glands produce sweat made of electrolytes and water. We’ve got eccrine glands on most of our body surface, and they release their sweat directly onto the surface of your skin. This sweat is what we release when we’re exercising or when it’s hot outside. 

Apocrine sweat glands are found in areas where you have hair, such as your armpits and groin. These glands release a milky fluid when you're stressed. Ceruminous glands, which make ear wax, mammary glands and the ciliary glands in your eyelids are subsets of apocrine glands. 

Apoeccrine sweat glands are sort of hybrids in that they have some characteristics of both eccrine and apocrine glands. They’re larger than eccrine glands and smaller than apocrine glands and are primarily located in the armpits and perianal regions. Apoeccrine glands make more sweat than either apocrine or eccrine glands. 

Sweat glands are activated by nerves responding to a variety of stimuli including:

• messages from the brain indicating that the body is too hot
• hormones
• emotions
• physical activity/exercise

Why does my sweat stink?

It doesn’t. The trouble starts brewing the second your sweat hits your skin and meets up with the bacteria that live there. The bacteria break our sweat down into acids, and that is what we smell. We call this body odor, aka B.O., but it is also called bromhidrosis, ozochrotia or osmidrosis. 

Most body odor comes from these body parts:

• armpits
• behind the ears
• belly button
• feet
• genitals
• hair
• the rest of the skin, but not as much

What’s it called when you don’t sweat enough?

Anhidrosis. If you don’t sweat normally, meaning if you don’t sweat you may be dealing with anhidrosis. We’re not talking about light sweaters, here. Anhidrosis is when your body literally cannot make sweat, which means it cannot cool itself, and that can be dangerous. Overheating can lead to heatstroke, which is potentially fatal.  

Treatment for anhidrosis varies, depending on whether the condition affects a large or small portion of the body. Anhidrosis that affects a small part of your body usually isn't a problem and doesn't need treatment. Treatments for larger areas of diminished perspiration depend what's causing the anhidrosis. If a medication is the culprit, your doctor may advise that you discontinue taking that drug, if possible. If you’ve got clogged sweat ducts, using a gentle exfoliant on the affected area might help.

What about when you sweat too much?

That’s hyperhidrosis. There are two types, primary focal hydrosis and secondary generalized hyperhidrosis. Primary focal hyperhidrosis is excessive sweating which is not caused by another medical condition. It’s also not a side effect of a medication. This type of excessive sweating is a medical condition in and of itself, occurring on particular areas of the body, on the left and right sides simultaneously. Usually, it will be hands, feet, armpits, face and head. People with primary focus hyperhidrosis will sweat in more than one of these. For example, if your hands are affected, your feet probably will be as well. Primary focal hyperhidrosis usually begins in childhood or adolescence and can run in families.

Secondary generalized hyperhidrosis is either a side effect of or caused by another medical condition or medication. That’s why it’s called secondary - it’s secondary to something else. People with secondary hyperhidrosis experience sweating on larger, generalized areas of the body. Another distinction between the two primary focal and secondary generalized hyperhidrosis is that people with secondary generalized hyperhidrosis sweat while they’re asleep. Secondary hyperhidrosis tends to start in adulthood. Primary hyperhidrosis starts in childhood or adolescence.  

Treatments can include prescription antiperspirant, creams containing glycopyrrolate, nerve-blocking medicines, antidepressants and/or botulinum toxin injections which blocks the nerves that cause sweating. Other treatments are sweat gland removal, nerve surgery or microwave therapy to destroy sweat glands.

Can you ‘sweat out’ toxins?

Nope. Sweat is NOT made up of toxins and therefore you don't 'sweat out' toxins. Rather, sweat is made up of 99 percent water and small bits of carbs, salt, protein and urea. Your liver and kidneys are the organs whose job it is to detox your body (not the sweat glands). 

If you have questions if your sweat levels are normal, contact an INTEGRIS Health primary care physician for further guidance.