Shave Underarm or Not?

Doubtless for most women, hairless armpits are about looks rather than health. But some might believe it lessens sweating. Is this true?
Humans have two primary types of sweat producers, known as eccrine and apocrine glands. Both types of glands are situated directly under the skin, but that's where the similarities end.
Eccrine glands cover most of the body and work as your own personal air conditioner. If your body becomes overheated, these glands empty an odorless solution made mostly of water and salt onto the skin's surface where it evaporates and cools the body.
Apocrine glands are located in areas rich with hair follicles, such as the groin and axilla (armpit) regions. Apocrine glands are activated by hormonal changes and emotional stress, and release a milky fluid made mostly of water, protein and fatty acids directly into hair follicles.
Although the fluids excreted by eccrine and apocrine glands are initially odorless, both emit a distinct odor when metabolized by the bacteria living on the skin's surface. Apocrine glands, for example, release fluid onto the skin through openings in hair follicles where it can comingle with fluid that originated in the eccrine glands. This blend can be consumed by bacteria on the skin's surface. As the bacteria break down the protein and fatty acids in the sweat, body odor becomes the byproduct [source: Mayo Clinic].

Shaving, Sweating and Smell
Unfortunately, shaving your armpits won't make you sweat less because the practice doesn't affect the glands that produce perspiration.
The apocrine glands that produce sweat are under the skin and not in the hair itself. These glands will continue to produce perspiration even when the hair is shaved down to skin level. The perspiration will continue to leak out of the hair's openings, even if there are fewer openings because the hair is shorter or shaved down to the skin [source: Mayo Clinic].
However, shaving armpit hair can help reduce body odor [source: Willacy]. Because hair is porous, it readily absorbs odors. If you've ever sat around a campfire or spent time in a smoke-filled bar, you'll know it doesn't take long for hair to absorb the smell. Underarm hair can trap moisture, too, creating a swampy environment that odor-causing bacteria revel in. So you may feel dryer (and therefore think you're sweating less) with shaved underarms.
If you're going to shave those pits, the best way to do it is to first expose the hairs to warm water; the heat and moisture will soften and draw out the follicle, making it easier to shave cleanly. Then, exfoliate to remove debris like deodorant or dead skin cells, and apply a shave gel or cream to lubricate and protect the skin. For underarm use, a razor -- even a disposable one -- should have a flexible, pivoting head with multiple blades.
Before you start shaving, lift your arm to touch the back of your neck. This will create a flat surface under your armpit and lessen the chance of getting nicked. And, because underarm hair sprouts willy-nilly, shave in all directions – up, down and sideways – before rinsing off the shave cream. When you're done, don't apply deodorant immediately because that can sting. Instead, allow the area to air dry first [source: SheFinds]