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How do skin blood vessels help regulate body temperature?

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Learn how regenerative properties of the skin helps to protect the human body from the external environment — human skin Human skin, whose cells are generated continuously by the body, serves as a protective barrier between the inside of the human body and the environment.

Human skin functions as a vital cooling device for the body by utilizing its extensive network of blood vessels to manage heat dissipation. This process is governed by a heat-regulating centre in the hypothalamus, which acts like a thermostat to control blood flow based on internal and environmental temperatures.12

When the environment is warm: The blood vessels dilate, allowing a free flow of blood to the skin's surface. This increases skin temperature and promotes heat loss to the external environment. During physical exertion, this flow becomes maximal to dissipate the heat generated by the body.21
When the environment is cold: The cutaneous blood vessels contract in rhythmic successions, restricting blood flow to the surface to conserve internal body heat.1

Additionally, the skin can control blood flow by using sphincterlike vessels to either direct blood through peripheral capillary beds or shunt it directly from small arteries to veins, bypassing the surface to further regulate temperature and blood pressure.1