How much blood does the average adult body contain?

The average adult body contains approximately five litres of blood, which is roughly 7-8% of the total body weight. This volume can vary based on factors such as body size, age, and overall health. Blood plays a critical role in transporting oxygen, nutrients, and hormones to cells, as well as removing waste products from metabolism. Maintaining this blood volume is essential for effective circulation and overall physiological function. This quantity is well within the range accepted in medical literature, which states that a healthy adult usually has between 4.5 to 6 litres of blood. Therefore, the choice indicating five litres aligns with established medical knowledge on human physiology.