Prevent Perspiration Stains On White Shirts With Baby Powder

The August 2007 issue of Real Simple magazine contains this tip: "Sprinkle a little powder on the underarms and the collar of a shirt, then iron. The powder forms a barrier that prevents oil and grime from seeping into the threads. " I assume you have to iron the powder into the inside of the shirt in order for this to be effective. At any rate, I haven't tried it yet, but if this tip works, then I will have recouped the magazine's subscription price ten-fold. Woohoo! Here's the link to the feature (hope it works): http://www.realsimple.com/realsimple/content/0,21770,1642864,00.html