The annoying thing about being a sweaty person — and I am, I am a bit ashamed to admit, a fairly sweaty person — is the way it sneaks up on you. It's never "Oh, the temperature is rising, therefore I am about to get sweaty." Rather, it's always, "How the hell did I get sweaty? It isn't even that hot!" For we sweaty folks, there's a certain helplessness to our condition, and this is right around the time of the year when it manifests itself the most, because the population's distribution of sweatiness seems so randomly, unfairly determined. All around us, we see friends, co-workers, family, and strangers with enviously dry skin. How do they do it? Why can't we be likethem?
To find out more about why some people sweat more than others, and whether there's anything that can be done about it, I reached out to Dr. Laure Rittié, a dermatologist and researcher at the University of Michigan Health System. Five really interesting points came out of our emailconversation.
1. Yes, you start sweating before you get that hot. The evolutionary purpose of sweating is, of course, to keep our temperature regulated. So the body responds pretty quickly even to subtle changes in temperature. As Rittié explained, "we sweat before we feel uncomfortably hot, and at lesser rates (instead of all of the sudden and profusely)." So that clamminess that comes before you even feel noticeably hot may be annoying, but it's normal and bydesign.
2. A lot of your sweatiness comes down to stuff you can't control, and was partially "set" when you were really young. Explaining why some people sweat more than others, Rittié said that "[w]e think this is because of the following interesting fact. Everyone is born with virtually the same number of sweat glands, but sweat glands mature during the first 2 years of life. Not all sweat glands become able to produce sweat (it depends on the need during that time). So people who grew up in warm climates tend to have more active sweat glands than people who grew up in a climate-controlled environment or in cold climates. As adults, we keep all our sweat glands but only a portion of them are able to produce sweat. This percentage varies betweenindividuals."
I asked her if she was aware of any genetic factors contributing to this, and she said no. So that leaves the environment you spend your early years in as a major contributing factor to how sweaty you are later in life. And parts of the developed world are so carefully and obsessively climate-controlled that it's easy to imagine that many of today's adults grew up in situations where their "climate" indoors had little connection to the part of the world they were from. All things being equal, one might expect people who grow up in hot parts of Africa without air conditioning to be much less sweaty than those who grow up in, say, the American Southwest with access toAC.
3. Your sweat glands also help your wounds to heal. Rittié's research has shown, as one recent press release put it, that "eccrine sweat glands, which are located throughout the body, are important for wound closure. They are major contributors of new cells that replace the cells that were lost due to injury." What this means is that the sweat glands that don't get "switched on" during those early years still have an important function. But as Rittié and her colleagues recently discovered, that wound-fixing function degrades as we age — "100 percent of sweat glands contribute to wound healing ... in young adults," she told me, but that number dips as weage.
4. You can maybe become less sweaty by not overdoing it with the AC all the time. "If you're exposed to 85 degrees often, the body will respond by starting sweating at maybe 82 instead (please note that in fact the body responds to internal temperatures, not external)," Rittié explained. "This is why 65 degrees in the spring usually feels warm while 65 degrees in the fall feels chilly. Why? The body is trained at the end of the summer but not in thespring."
I asked if our summertime behavior might have an impact here: Since scurrying from air-conditioned building to air-conditioned building prevents us from acclimating to hot temperatures, could going easier on the AC help out people who feel they sweat too much? "Definitely!" she said. "That would be part of sweat-gland training to achieve more regular and controlledsweating."
5. If you want to sweat less, cold water is probably a much better bet than an ice pack. This isn't all that surprising, but it points to an important, underappreciated fact about sweating: Our body is responding to our internal temperature, not our external temperature, as Rittié pointed out. Holding a cold pack up to your forehead (or anywhere else) "would cool you off somewhat by cooling down the blood that circulates in the skin that is in contact with the cold pack," and "might also provide a sense of relief, especially when applied to areas where skin blood flow is the highest (cheeks for instance). But a cold pack remains a relatively small surface area compared to the rest of the body so this may not be obviously the most efficientway."
Drinking cold water is much more effective, though, because of that external/internal thing — you get a lot more internal cooling out of a cup of chilled water heading down your throat and into your stomach. "Visualize cooling down the content of your stomach and thereby cooling down internal organs," Rittié suggested. For those of us not looking forward to being drenched for large portions of the next three months, it's definitely worth ashot.