How Much Blood Is in the Human Body?

The blood in the human body makes up around seven percent of its weight. CREDIT: Dreamstime View full size image

Enough to fill one or two one-gallon milk jugs.

Blood accounts for about seven percent of human body weight, and its density is only slightly more than that of pure water.

Blood is made up of plasma (which accounts for about 3 liters), red blood cells, white bloods cells, and platelets. Vitamins, electrolytes and other nutrients are dissolved in the blood and carried to the body's cells and organs.

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