Scents and science mingle in entertaining ‘Joy of Sweat’
By Jennifer Szalai
In “The Joy of Sweat,” an entertaining and illuminating guide to the necessity and virtues of perspiration, science journalist Sarah Everts points out that plenty of people pay good money to exude sweat while also paying good money to hide it.
Saunas, spin classes and hot yoga, yes; but also deodorant, dress shields and antiperspirants that deliberately create what Everts calls (vividly and unappetizingly) a “sweatpore plug.”
“This vital life process, one that we all possess, one that helps make us human, is deemed embarrassing and unprofessional,” Everts writes. “How did that come to be?”
Sweat helps to keep us alive. The human body produces a lot of heat, even when it seems to be doing nothing. Start to move and exert yourself, especially when the weather itself is hot, and your body will produce even more.
Our eccrine glands, which Everts describes as “tiny, elongated tubas embedded in skin” with “extensive coiled piping” at the base, release fluid that evaporates off our hot skin. Without this mechanism, our bodies would succumb to heatstroke, with organs failing, blood hemorrhaging, bacteria breaching intestinal walls.
Then there’s the other kind of sweat, which comes from the larger apocrine glands, located in places like the armpits and the groin. These glands ooze “waxy, fatty molecules” that are especially appealing to bacteria, whose feasting produces a chemical waste. This waste is what stinks. Sensory analysts have identified the component scents in human armpit odor, which include “rancid butter” and “wet dog.”
But the human cooling mechanism could be much worse, Everts says — less effective and even smellier. Nonhuman animals either don’t sweat, or they don’t sweat as efficiently as we do. (To “sweat like a pig” would entail not sweating enough, so that we would have to roll around in the mud to halt overheating.) Some scientists posit that our cooling system is what allowed humans to forage for food in the sunshine for hours while predators languished in the shade.
Everts is a crisp and lively writer, along with an ability to put abstruse scientific processes into accessible terms. She tethers her scientific interludes to scenes in which she’s doing some unlikely things — getting her armpits sniffed by an analyst in New Jersey, participating in a “smell-dating” event in Moscow, watching a man engulfed in a dry ice vapor during a “sauna theater” performance in the Netherlands.
A lot of our hang-ups about sweat turn on the issue of smell. This is especially true in the United States, where the analyst who sniffs Everts’s armpits observes that — unlike in the expert’s native France — scent consumers are looking not to complement their body odor but to ensure its “annihilation.”
Our attitude to smell isn’t exactly one-note, though. Everts also examines the cultural obsession with pheromones, and the idea that odor messages are somehow irreducibly authentic. We can try to cover them up, but we can’t calibrate them — hence the smell-dating event, or the peddling of pheromone colognes that are supposed to make men irresistible to women, though their efficacy is dubious.
“The problem is these products are more likely to attract a horny sow rather than a horny human female,” Everts writes.
The biggest crisis looming over the subject, which Everts explicitly acknowledges at several points, is global warming.
“Our ability to sweat may be foundational to the resilience we’ll need to get through the coming climate apocalypse,” she writes, though the excess humidity that comes with changing weather patterns may render our sophisticated cooling mechanism moot. When it’s too humid, sweat can’t evaporate.
One thing I couldn’t stop thinking about was how each person’s individual scent combines with another person’s individual scent receptors. “Even if you think you know your own smell,” she writes, “you may not know how others are experiencing it” — a terror or a comfort, depending on how you see (or smell) it.