I stopped armpit sweat overnight with one neat trick: I switched from antiperspirant to deodorant. Backwards, I know. Read on...
About 8 months ago, I developed a rash in my armpits. It turned out to be a nasty-ass case of ringworm. It's all gone now, thanks to a fuck ton of cream and maybe tea tree oil soap. Before I knew what it was, I decided to try an experiment. I'd heard bad things about antiperspirant use and, while I'm not normally one to just try something that some uneducated yahoo suggests on the Internet, I decided to give it a shot - maybe antiperspirant was somehow giving me a rash?
The serendipitous results were instant and dramatic. Within two days of switching to deodorant, I had virtually no sweat in my underarms, as evidenced by the lack of gross-ass wet spots on my undershirt. I thought maybe it was residual antiperspirant still hard at work, but after several days and showers, still no sweat.
Some background: I've been using antiperspirant my entire teen/adult life, with varying levels of success. I've always sweated somewhat while wearing it, but chalked it up to "it works ok I guess but holy shit imagine how much I'd be sweating if I didn't use antiperspirant". In fact it's always baffled me that people would use deodorant when antiperspirant is right there next to it on the shelf. Why would you use an inferior product? That's like ordering a cheeseburger, hold the cheese.
Several years ago, the sweating got worse, to the point where I had to start wearing undershirts to absorb the sweat so that it didn't show. So I was at a point where my outer shirts were no longer drenched, but my inner shirts looked like hell even after I washed them because oh hey neat side effect of antiperspirant: it turns out that it ruins your shirts. From the yellow armpit stains to the actual glitter that you can see in strong light, it's aluminum-based compounds in your antiperspirant that are to blame. Click here to read more.
This whole thing is counter-intuitive. Antiperspirant is supposed to stop you from sweating, with chemicals and medicine and shit, whereas deodorants are just there to make you smell nice, right? I was surprised to learn that deodorants, besides the fragrance aspect, actually have antimicrobial compounds that kill the bacteria that makes your armpits smell in the first place. Oh did I mention that it's not the sweat that stinks, it's the bacteria? The bacteria thrive in a moist environment, so the strategies are to either a) reduce the moisture (antiperspirant) or b) reduce the bacteria in the first place (deodorant).
I'm confused because I'm now performing scenario b) above, and yet experiencing scenario a) for a final result of c) not sweating and also smelling nice. How is this happening? No fucking clue. Maybe it's some sort of sweat feedback loop, where my body overcompensates for the blocked sweating by somehow being able to sweat more? I don't know. It's bizarre but hey it works and I'm not the only one.
There are other examples of people having the same experience as me, but there are also people who swear by antiperspirant over deodorant. So you'll have to figure out your special recipe. But if you, like me 8 months ago, seem to sweat buckets despite daily antiperspirant use... this might be right for you. Do some reading, don't just listen to me. If you come across this in your internet research... don't believe the hype about aluminum compounds in antiperspirant causing breast cancer and Alzheimer's, those claims have been thoroughly disproven.
Oh and here's fun: enjoy listening to bodybuilders talk about sweaty armpits. Those guys sound about as educated as you'd expect, brah