Is skin temperature as constant as body temperature?

Because human beings are warm-blooded animals, their body temperature is constant between 36℃ and 37℃, so some people think that the skin temperature is as constant as the body temperature, which is actually wrong. Human tissues, organs and skin vary greatly in different parts.

The temperature of human liver is the highest, followed by blood vessels and muscles, and finally the skin. The temperature of the skin is generally lower than 37℃, which is influenced by the blood circulation in the skin and the external temperature. The general rule is that the trunk is higher than the limbs, and the proximal end of the limbs is higher than the distal end. The skin temperature of head, face and palm with rich blood circulation is also higher, and the lowest is auricle, nose tip and fingertips. The change of outside air temperature also has obvious influence on skin temperature, such as the chest skin temperature is 36.6℃ and the thigh skin temperature is 33.6℃ in summer; In winter, the chest temperature is 36.4℃, and the hand temperature is only about 10℃, which is very significant. If the heat preservation is improper, frostbite is easy to occur.

Microcirculation of skin plays an important role in regulating body temperature. When the temperature rises inside and outside the body, the blood flow of skin microcirculation increases, the flow velocity accelerates, the blood vessels dilate, sweating increases and heat dissipates; On the contrary, when the body produces less heat and the outside temperature is low, the skin blood flow decreases, the flow rate slows down, and the blood vessels contract to prevent the skin from losing heat. Many people think that drinking can drive away the cold, which is not entirely correct. Drinking can dilate blood vessels in skin microcirculation, increase blood flow, temporarily warm the skin and dispel the cold, but at the same time accelerate the loss of skin heat. Once the effect of ethanol disappears, it will make you feel colder. Moreover, when you drink too much and get drunk, the regulation function of blood vessels in skin microcirculation will be paralyzed, and your resistance to cold will be greatly weakened, which will easily lead to frostbite and frostbite. Therefore, it is not recommended to drink to keep warm in winter, and it is forbidden to go out when you are as drunk as a fiddler.