Information for Preteens:
Body Science, About Armpit Odor
(AKA stinky pits)
Have you recently started to notice that your armpits don't smell quite so nice? Well, armpit odor – also known as axillary malodor – is caused by bacteria!
You, and everyone else, have two types of sweat glands: apocrine (ah-poe-krin) and eccrine (ek-krin). Glands are special pockets in your body that store and then release things as needed. The eccrine gland stores mostly water to help cool you down when you're hot. The apocrine stores sweat.
Harmless bacteria live full-time in your armpit. A smelly odor develops when these bacteria eat your sweat. This type of bacteria, called coryneform (ke-rin-neh-form), breaks down sweat and releases the chemical 3-methyl-2-hexenoic acid, basically a fancy form of that distinct armpit smell that sort of burns your nose.
Interesting Puberty Fact
Ever noticed that little kids don't have stinky pits? That is because your sweat glands become more active during puberty, leading to stinky pits.
The odor starts around the same time you start getting hairs around your genitals and under your arms and about one year before you have your first period (for girls) or a wet dream (for boys).