Underarm Sweating
Eccrine Gland
The eccrine gland is the workhorse of sweating — the gland doing the actual cooling almost everywhere on the body.
Eccrine glands are the most numerous sweat glands, spread across nearly the whole body. They produce the thin, watery sweat that cools you as it evaporates, and they respond mainly to heat and physical effort. They are the body's primary temperature-control glands.
What an eccrine gland is
Eccrine glands are small sweat glands found over most of the skin, in especially high numbers on the palms, soles, and forehead. They open directly onto the skin surface and release a thin, watery, largely odorless sweat.
Their main job is temperature control: as that watery sweat evaporates, it carries heat away and cools the body. They answer chiefly to heat and exertion, though the palms and underarms also respond to stress.
Their role in cooling
Because eccrine sweat is mostly water and evaporates readily, it is the body's core method of shedding heat. This is why you sweat more in warm weather and during exercise, and why the sweat itself does not smell.
Eccrine versus apocrine
The other main type, the apocrine gland, is concentrated in the underarms and groin and makes a thicker secretion tied to odor. The underarm is one of the few areas rich in both, which is why it responds to heat and to emotion at once.
Frequently asked questions
What is the difference between eccrine and apocrine glands?
Eccrine glands are everywhere and make watery sweat that cools you in response to heat. Apocrine glands are concentrated in the underarms and groin and make a thicker secretion tied to odor and to stress and hormones.
Where are eccrine glands most concentrated?
They are densest on the palms, soles, and forehead, which is why those areas sweat so readily — including in response to stress, not only heat. They are present across almost the entire skin surface.
Sources & further reading
Reputable organizations with more on sweating and related topics. Offered for further reading and general education, not as citations for any specific claim on this page.
General educational information about sweating. Not medical advice, and not a substitute for diagnosis or treatment by a qualified healthcare professional.