Thermoregulation

Thermoregulation is the set of physiological and behavioral processes that keep body temperature within a range compatible with normal cellular and organ function despite changes in environmental temperature or internal heat production. In humans, it depends on balancing heat produced by metabolism with heat exchanged between the body and its surroundings .^1,2

Temperature-sensitive nerve endings in the skin and internal tissues provide information about thermal conditions to the nervous system. The preoptic region of the hypothalamus is an important coordinating center that integrates thermal signals and regulates responses that alter heat production, heat conservation, and heat loss .^1,2

When the body becomes too warm, increased blood flow to the skin enhances heat transfer from the body core toward the skin and can facilitate heat loss to the environment, while sweating allows heat to be lost as water evaporates from the skin. During cold exposure, constriction of skin blood vessels reduces heat loss, and shivering increases heat production through repeated skeletal-muscle contractions. Behavioral responses, such as seeking shade, changing clothing, or moving to a warmer environment, also contribute substantially to temperature regulation .^1,2

Thermoregulation does not maintain body temperature at one perfectly fixed value. Core temperature varies normally with factors such as time of day, physical activity, and physiological state. Thermoregulation refers instead to the coordinated control mechanisms that limit and appropriately adjust these temperature changes .¹