How did bloodletting stop the four humors?

Bloodletting was a medical practice based on the ancient theory of the four humors—blood, phlegm, black bile, and yellow bile. It was believed that an imbalance among these humors caused illness, and bloodletting was thought to restore equilibrium by reducing excess blood, thereby alleviating symptoms related to the "hot" conditions attributed to an excess of blood. By removing blood, practitioners aimed to correct this imbalance, thus helping to restore the patient's health according to the humoral theory. However, modern medicine has since discredited this practice as ineffective and harmful.