Photo by Shashank Shekhar on Unsplash.

After a relatively gentle and temperate spring, summer has well and truly arrived in force. And as temperatures rise, humans start sweating to help keep cool. Perspiration is but one finely tuned part of your body’s many regulatory systems, and it turns out that getting sweaty is a bit of a human specialty. While many other mammals perspire in small amounts, humans and horses are the only ones to use sweat as a primary means of regulating temperature: other mammals like dogs have to pant to cool themselves down on a hot day. While the modern human would probably rather take advantage of air conditioning, fans, and trips to the river to cool down, during our hunter-gatherer phase, our ability to sweat was a crucial part of the toolkit which allowed us to become the planet’s premier exhaustion hunters and apex predators. It didn’t matter if our prey was faster, stronger, or more stealthy: we didn’t stop. Sweating was a surprisingly big part of that capacity for endurance. And it worked because here we are today writing articles about it.

Smell

The “smell” commonly associated with sweat is produced by the bacteria which live on your skin.

There are two types of sweat glands on the human body. The ones in our armpits are called the apocrine glands and they produce the kind of sweat we associate with human body odor. The ones everywhere else are called eccrine glands, and they produce a less-pungent sort of sweat. Through the phenomenon of evaporative cooling, sweat keeps our body temperature at a safe level and also helps cool down any muscles which have heated up from use. The “smell” commonly associated with sweat is actually produced by the bacteria which live on your skin, who feast on your sweat and produce an aromatic byproduct free of charge. How much and on what areas of the body a human will sweat are determined by the age, fitness level, sex, and genetics of the human in question. Generally speaking, more physically fit individuals will sweat more readily, but heavier and less-fit folks are also likely to sweat more when they heat up, but less efficiently than those whose bodies are more acclimated to heat and exertion.

Attraction

Sweat is mostly composed of water, although trace amounts of minerals (including sodium, potassium, calcium, and magnesium), lactic acid (from hard-working muscles), and urea (you can look that up yourself) are usually present as well. Sweat also contains pheromones, which grants each of us a unique scent profile. Acclimation to these scents plays an important part in human reproductive signaling, sexual attraction, and bonding – simply put, it is likely that mate selection is influenced by whether or not someone’s sweat smells “good”.

Immunity

Do not hesitate to speak to a medical practitioner if you think you’re sweating more than normal.

In addition to helping us stay cool and keep up in the dating game, our sweat has antimicrobial qualities, helping to evict unwanted bacteria and fungi that might be setting up shop on the old epidermis. Earwax, tears, saliva, and even breast milk have been shown to have similar defensive capabilities, making our sweat an effective if sometimes stinky part of our innate immune systems.

While most of the time sweating is a natural part of our body’s many processes, strong emotions, recreational drugs (including caffeine and alcohol), excitement, fear, and trauma can all cause an excess of sweating. Furthermore, a number of potential medical issues are often accompanied by hyperhidrosis or excessive sweating, including diabetes, heart issues, and leukemia: do not hesitate to speak to a medical practitioner if you think you’re sweating more than normal. Hypohidrosis often goes untreated and undiagnosed due to embarrassment or a lack of awareness, and can lead to further physiological and emotional complications if ignored.

Galen Lastko, submitted on behalf of the SoHum Health’s Outreach department.