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How does the hypothalamus regulate human body temperature?

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The hypothalamus acts as the body’s primary thermostat, maintaining homeostasis by integrating temperature signals from the skin, spinal cord, and deep body tissues. It monitors the temperature of the blood flowing through it and coordinates involuntary responses to keep the core temperature near 37 °C (98.6 °F).123

When the hypothalamus detects that the body is too warm, it initiates heat-loss mechanisms:
* Vasodilation: Widening of blood vessels in the skin to increase blood flow and heat dissipation.23
* Perspiration: Increasing sweat production to cool the body through evaporation.13
* Reduced activity: Lowering metabolic and muscular activity to decrease internal heat production.1

When the body is too cold, the hypothalamus triggers heat-conservation and production mechanisms:
* Vasoconstriction: Narrowing of skin blood vessels to reduce heat loss.23
* Thermogenesis: Generating heat through shivering and the activation of brown adipose tissue.12
* Behavioral changes: Stimulating feelings of discomfort that motivate individuals to seek warmth or shelter.2

These autonomic processes ensure survival by maintaining a stable internal environment despite external fluctuations.12