1.？ Environmental factors: There are two kinds of sweat glands in human body, one is exocrine sweat gland, also called eccrine sweat gland (eccrine sweat gland translation: mainly distributed in armpit, areola and umbilical fossa). Its composition is similar to that of plasma, and it contains electrolyte besides water. )。 The other is apocrine gland, also called apocrine gland. Apocrine glands are distributed all over the human body. Because more than 99% of the sweat it secretes is water, it is generally colorless and tasteless. When the human body sweats a lot and fails to clean it in time, the sweat will penetrate into the stratum corneum of the skin, so that protein and lipids will be decomposed by bacteria parasitic on the skin surface, resulting in peculiar smell.
2.？ Heredity: bromhidrosis generally originated in adolescence, so it is more serious in young adults. Studies have confirmed that the disease is an autosomal dominant genetic disease. About 80% patients with osmidrosis have obvious genetic tendency. If one parent suffers from bromhidrosis, about 1/2 of their children suffer from bromhidrosis; If both parents suffer from bromhidrosis, about two-thirds of their sons and daughters will suffer from bromhidrosis; If children whose parents have bromhidrosis don't have bromhidrosis, their offspring will not suffer from bromhidrosis again.
3.？ Hormone level: the concentration of dihydrotestosterone in the sweat gland nucleus of patients with osmidrosis is higher than that of testosterone, and the levels of androgen and cytoplasmic sex hormone receptor in the sweat gland nucleus of patients with osmidrosis are higher than those of normal people. At the same time, the activity of 5α- reductase in the apocrine glands of these patients is high, and 5α- reductase type I plays a major role in androgen metabolism.
4.？ Thick hair: experts say that people with thick hair are relatively rich in sweat glands, especially under their armpits.
5.？ Endocrine disorder: excessive excitement of sympathetic nerve, increased nerve impulse of sweat secretion by sweat glands, will induce bromhidrosis.
6.？ Mental stress: when you are emotional and nervous, the endocrine balance of the human body will be destroyed, which will make the apocrine glands secrete actively and easily produce underarm odor.
7.？ Living habits: Personal hygiene is closely related to body odor. Bad living habits often lead to underarm odor. There are many places in the human body that are not conducive to cleaning, such as under the breast, groin, armpit and navel, with many wrinkles and more secretions than other parts. Many young men and women like to wear tights, jeans and so on. Cause the skin to cling to the clothes, prevent the secretion from evaporating, and make these local temperatures and humidity high, and some bacteria are here.
8.？ Interaction between sweat gland secretion and microorganism: Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus and Staphylococcus coryneform in armpit skin act on sterile and tasteless sweat gland secretion, resulting in unpleasant smell. Related studies have confirmed that diphtheria-produced enzymes play an important role in regulating the formation of bromhidrosis.
9.？ The taste is fat, sweet and thick: especially red meat containing protein and high fat, people who eat more meat are acidic, and too many acidic substances are produced during metabolism, and sweat will be acidified to produce odor.