Why do people sweat in their underarms?

Humans have apocrine glands in their underarms, which produce a milky fluid when stimulated by hormones such as adrenaline. Bacteria on the skin feed on this fluid, breaking it down into waste products that smell like body odour. When a person is sweating, the moisture provides an ideal environment for these bacteria to grow and multiply, which can make body odour worse.

People sweat in their underarms for several reasons, including:

Genetics: Some people are simply more prone to sweating than others due to their genetic makeup. This can be due to the number of sweat glands a person has, as well as how sensitive these glands are to heat and other triggers.

Hormones: Sweat glands are stimulated by hormones such as adrenaline, which is produced in response to stress, anxiety, and physical exertion. This is why people often sweat more when they are nervous or stressed. Hormonal changes during puberty and menopause can also lead to increased sweating.

Heat: Sweating is the body's way of cooling down, so it's natural to sweat more when the temperature is high. This is why people often sweat more in hot weather or during physical activity.

Clothing: Wearing tight-fitting or restrictive clothing can trap heat and moisture in the underarms, which can make sweating worse. Certain materials, such as polyester, can also irritate the skin and make it more prone to sweating.

Health conditions: Some health conditions can also cause excessive sweating, such as hyperthyroidism, diabetes, and obesity. If you are concerned about excessive sweating, it is important to talk to a doctor to rule out any underlying medical conditions.