Because adrenaline can make people's blood vessels dilate (called vasodilation) and speed up blood flow and oxygen delivery, blood vessels will respond to the signal sent by the chemical transmitter adenylate cyclase, so that adrenaline will prevail, the veins on the face will expand, resulting in more blood flowing through the blood vessels, and people's capillaries will expand, which will lead to blushing.

To put it bluntly, when you feel embarrassed, it is the cerebral cortex that stimulates the adrenal gland and secretes a small amount of adrenaline, so your face is hot and red.

Extended data:

Blushing can also be cancer.

Frequent facial flushing, frequent diarrhea, abdominal pain, recurrent hypoglycemia and even asthma ... These seemingly unrelated symptoms may actually point to the same disease: it once took away Steve Jobs, the founder of Apple, who was admired by many "fruit fans", and also devastated male and female patients from cardamom teenagers to elderly people.

Although it mostly occurs in the digestive system such as gastrointestinal pancreas, it has a strange name "neuroendocrine tumor". Experts pointed out that the symptoms of the disease are complex and changeable, and the treatment should not rely on specialists to fight alone, but should take the road of "multidisciplinary diagnosis and treatment".

Neuroendocrine tumors are a group of highly heterogeneous tumors, not a single tumor that is usually recognized, but a general term for a large class of tumors. Neuroendocrine tumors can occur in many organs and tissues of the whole body, and gastrointestinal and pancreatic neuroendocrine tumors are the most common, accounting for about two-thirds of all such tumors.

People's Daily Online-Why do people blush when they are shy?

People's Daily Online-Blushing may actually be cancer. How to see health from the face?