Why Wool Doesn't Stink
by Mary Stipe
There are two kinds of sweat glands: apocrine glands, the type found in your armpits, andeccrine glands, the type found everywhere else. Eccrine gland secretions don't smell, and thank goodness. But apocrine gland secretions are released through the same pores as the oil glands, and when bacteria on the skin's surface feeds on the fats in these secretions, run for cover and plug your nose!
When this happens, the last thing you want to do is trap the moisture on your body and in your clothing. Unfortunately, that's exactly what happens with most synthetics. But not with wool. Wool is "hygroscopic," which means it easily absorbs moisture. Although other natural fibers have this ability, none beats wool. Moisture passes through it and is released into the air instead of remaining on the skin.
Wool absorbs about 30 percent of its weight in moisture, so it can hold that much without making you feel clammy. Nylon absorbs 4.5 percent, and polyester, just 0.4 percent. With these fibers, moisture remains on the skin and the surface of the fabric, giving that bacteria a veritable feast. You get the leftoverssticky skin and a pungent aroma.
A fabric's ability to wick moisture does not make it immune to this, as anybody who has sweated in high-wick fabrics can attest.
Mary Stipe is a freelance writer specializing in textiles. At least, she was when she wrote this about ten years ago. Mary, what are you doing now?