Powder your bum with food.

May 15, 2009 2:15 PM

Starch is food. So, why do we put cornstarch on skin to prevent, and dry up, topical skin infections, like diaper rash? I know from experience that it works. Why can't the infection use the starch as a food source?
posted by Foam Pants to Health & Fitness (5 answers total)

You're talking about applying cornstarch to topical inflammations, not infections. There are no bacteria to feed.
posted by mudpuppie at 2:17 PM on May 15, 2009

Yeah..you don't want to put cornstarch on an infection. I know for a fact that cornstarch will exacerbate a yeast infection.
posted by zerokey at 2:27 PM on May 15, 2009

Corn starch is useful largely due to its hygroscopic properties. It gets rid of that wetness that causes irritation of the skin. This also helps prevent fungal or bacterial infections because it dessicates the microorganisms.
posted by chrisamiller at 2:27 PM on May 15, 2009

Sugar is a food as well but jam preserves work because there's too much of it relative to the water available in a mixture and the micro-organisms don't function properly.
posted by bonobothegreat at 2:32 PM on May 15, 2009

Bacteria need moisture to thrive, not just a source of food. Also, like mudpuppie said, nobody puts starch on infections, just on inflammations and sometimes burn blisters, where typically no harmful bacteria is present. Cornstarch also forms a silky smooth barrier on the skin to prevent exacerbation of the rash due to chafing.
posted by halogen at 2:36 PM on May 15, 2009