Why Does the Armpit Tend to Sweat Excessively?

In hot summer, excessive sweating in the armpits can not only make the clothes look wet and unattractive, but also sometimes emit unpleasant odors, which can be embarrassing when people are in close contact with others. In fact, some reasons for excessive armpit sweating are normal and do not require treatment. However, other reasons may indicate an underlying medical condition that requires timely treatment. So what are the causes of excessive armpit sweating? Let's take a look.

1. Temperature: Sweating is a natural way to regulate body temperature and dissipate heat. During the hot summer, the temperature is high, and the armpits naturally sweat more than usual.

2. Diet: Regular consumption of spicy foods such as garlic, onions, cruciferous vegetables, peppers, and curries can raise body temperature. Caffeine, often found in coffee, can stimulate the nervous system and also contribute to excessive armpit sweating.

3. Strenuous Exercise: During exercise, when the environment is too hot or the workout is intense, nerve cells send messages to the hypothalamus. As a response to heat, the hypothalamus activates the sweat glands, leading to sweating in the armpits.

Tips: Generally, healthy individuals tend to increase sweat gland secretion during exercise or exposure to high temperatures. This is a physiological mechanism to lower the rising body temperature. Therefore, obese individuals often sweat more than thinner individuals. This is not due to their larger surface area but rather because their higher body weight leads to an easier increase in body temperature, necessitating more sweating to regulate it.

Apart from the above reasons, excessive armpit sweating when not normally expected may indicate issues with the sweat glands. Localized excessive sweating can be caused by sympathetic nerve damage or abnormal responses, leading to increased acetylcholine secretion and overactive sweat glands.

1. Abnormal Apocrine Sweat Gland Secretion: The apocrine glands in the armpits secrete organic substances. When these substances are broken down by bacteria, they produce unsaturated fatty acids, causing sweating and emitting an odor in the armpits. During summer or slight physical activity, influenced by endocrine factors, the apocrine glands secrete more, resulting in a slight odor.

2. Diseases: Medical conditions such as thyroid hyperfunction and diabetes can affect sweat gland secretion, leading to armpit sweating. Sympathetic nerve damage or abnormal responses can increase acetylcholine secretion, causing excessive sweating from the small sweat glands. Additionally, hypertension, menopause, and the effects of adrenal cortical hormones can also contribute to armpit sweating during summer.

3. Hyperhidrosis: Hyperhidrosis is a condition characterized by frequent, excessive, and unexplained sweating. Primary hyperhidrosis results from overactive sweat glands, leading to excessive armpit sweating. Secondary hyperhidrosis is associated with health issues such as menopause, hypertension, and heart disease.