I know a lot of women who do this. Maybe it is regional? I live in the South.
It's *supposed* to leave one dry and fresh. I used to do it, only occasionally, until I found out how dangerous talc is. I haven't done it in years and years, though. I have never sweated profusely; by the end of the day it was pretty much normal down there, as far as the powder.
My cousin died at a young age of ovarian cancer; it may have originated as cervical cancer, I'm not sure. But I found out later that she practiced this religiously. It was very sad; she left a husband and little ones behind.
Cornstarch is supposed to not be dangerous, but my mom insists that the talc powder "smells better" and I had to work hard to keep her from using it on my daughter.
If powder "must" be used, they recommend only a small amount of cornstarch in the bottom of the diaper, not on the diaper area, and not shaken in a puffy cloud where it can be breathed in. I also read that talc is very similar to asbestos
I've always heard cornstarch is okay but talc is definitely a no-no for babies or adults. I actually know a lot of people who do this too, in the summer. I'm from a very humid area more than anything else. Every day in the summer you can be guaranteed 90 degrees and up and humidity of sometimes 80-90%. I think it isn't just for the sweating issue, but for chafing?! I know my mom used to put it under her boobs where they were saggy from having kids and it would rub. She refused to wear underwire bras so....
Funny guano -- I went to a Tom Jones concert with my mom many many years ago. He puts powder in his pants because he sweats so much with all that movement. At one point, his son ran up on stage to tell him his black pants were turning white. He had to go change, after explaining.
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