The Joy of Sweat: The Strange Science of Perspiration | Author: Sarah Everts
The book tackles the physiology, culture, and science of sweat. Understanding why we need to sweat provides an appreciation and gratitude for our body’s way of regulating temperature. It also makes us question the social forces that tell us to hide our sweat or feel shame.
We Love It. We Hate It.
Society’s aversion to sweat is two-pronged: optics and the odor. For all our efforts to regulate and minimize the effects of sweat in certain situations, we also associate sweat with health and purification. Take for instance the sauna or hot yoga.
Unpacking society’s relationship with sweat, the author provides a historical explanation of the marketing strategies that engrained deodorants and antiperspirants into our grooming rituals. The author elaborates on the misguided notion of how we detoxify when sweating. This is an antiquated knowledge from the Greek physician Galen. We know that our kidneys filter toxins.
The author clarifies that “sauna is not a detox strategy or exercise. Kidneys are responsible for detoxification”, but points to some benefits:
The heat in the sauna causes blood vessels to dilate, or to widen, which allows more blood to travel through your circulatory system. Wider veins means it takes less thrust from your heart to push your blood around your body, so your blood pressure drops.
The Joy of Sweat
The book also dedicates the last chapters to the ongoing research on sweat and society. The author talks about how law enforcement can use sweat to solve crimes. The book explains the types of surgeries and medical procedures to control excessive sweating or the condition of not sweating at all.
The book answers some fundamental questions about sweat. What is in our sweat? Can you transfer sweat odor form one person to another?
Why Do We Sweat?
Compared to other animals, sweating to keep us cool and alive makes us more efficient. Australian fur seals pee on themselves to cool off. Honeybees vomit. Storks defecate. In fact, evolutionary biologist argue that humans dominate the natural world because of our cooling system.
And it’s not just hot weather that leads to body heat. Our bodies produce heat from all the work our cells need to do to keep us alive.
You can’t be physically active without sweating and we can’t control sweat, unlike urine for example. Although as a society, we are fine sweating at the gym or outside on a hot day, some situations can make us feel awkward. Such as sweating at the office.
Our Sweat Glands: Eccrine and Apocrine
The millions of microscopic organs responsible for dispatching salty, cooling sweat to skin are called eccrine glands.
The salty cooling sweat is one of two kinds of perspiration produced by human bodies. Our other sweaty discharge comes from apocrine glands, which become active at puberty. These are the sweat glands notorious for morphing armpits into stink zones during adolescence. These are bigger than eccrine glands.
The Joy of Sweat
What Makes Up Sweat?
Eccrine sweat is chemically similar to blood’s watery base—it’s pretty much blood minus the red blood cells, platelets, and immune cells.
(Aside from bodily fluids), food and drugs…can percolate out in perspiration. Nicotine, cocaine, garlic odor, food dyes, amphetamines and antibiotics, they all trickle out this route…
…sweat’s chemical components also include hundred of molecules normally found in bodies: waste products from exercise, such as lactic acid, and urea, as well as glucose and some metals.
The Joy of Sweat
Sweat also contains proteins from our immune system and sweat carries markers of disease.
Why Does Sweat Have a Smell?
…apocrine glads begin oozing waxy, fatty molecules into the armpit. Although expelled in microscopic quantities and odorless themselves, the waxy molecules are like candy to the millions of bacteria living in armpits…as microorganism devour and metabolize the greasy apocrine molecules, they produce chemical waste. It’s the waste–in effect, bacterial poop–that makes us stink.
If you have a higher percentage of Corynebacterium, there’s a good chance you’ll produce a more potent and objectionable aroma.
The Joy of Sweat
Do Men and Women Sweat Differently?
On average there’s little evidence to support major sex difference in sweating: Women tend to have more sweat glands per unit area and men tend to have a higher max sweating rate, but many of the sex differences reported can be attributed to other factors such as body size, aerobic capacity, or exercise intensity.
The Joy of Sweat
Why Do I Sweat When I’m Anxious?
Sweat glands don’t just open when we’re hot. They can also go rogue in moments of anxiety…the hormone adrenaline and its sibling noradrenaline, which kick open both eccrine and apocrine glands. These hormones circulate in our blood when we are sexually aroused, emotional, or just plain stressed.
The Joy of Sweat
Can We Transfer Body Odor from One Person to Another?
The author references a researcher from the University of California, San Diego, @DrArmpit and his experience on how sleeping with someone with a particular odor got transferred to his own.
How Were Antiperspirants and Deodorants Marketed When They First Came to Market?
The logic for marketing the products seem to follow this evolution:
- Scare women into thinking that they can’t get a man with sweaty pits.
- Even if women marry, keeping him means maintaining fresh smelling dry pits.
- Getting women to buy one for your man. He especially needs deodorant and antiperspirant at the office.
- Teenagers need it.
The Takeaway
Witty writing, engaging stories, and laden with knowledge on the physiology of sweat, this book makes you appreciate this important bodily function. Perhaps one of my favorite quotes from the book:
Why don’t we delight in our ability to produce perspiration the way we revel in the ability of a spider to produce silk? I’d wager your average spider isn’t self-conscious about the sticky stuff flowing from her body.
The author tells stories of people that sweat too much or don’t sweat at all. These conditions hamper life beyond cultural norms. I get why some people opt to have surgeries. But if the inconvenience of sweating doesn’t extend beyond social stigma against sweat, it might be time to rethink our practices.
There are celebrities that have admitted to ditching deodorants or antiperspirants, Julia Roberts, Brad Pitt, Cameron Diaz, Kourtney Kardashian, and Shailene Woodley to name a few. Maybe that makes a difference. But more than celebrity endorsement, it’s on us to refrain from making assumptions about people who sweat in places and situations we deem inappropriate (i.e. office, date) and appreciate the life we get to live because of our sweat.
As always, this review is not meant to forgo the reading of the book. But the provide nuggets of core information to make you want to read more.
