Where are nutrients exchanged in the body?

Nutrients are exchanged primarily in the capillaries, which are tiny blood vessels that permeate tissues throughout the body. In the capillaries, oxygen and nutrients from the blood diffuse into the surrounding cells, while waste products and carbon dioxide move from the cells into the bloodstream. This exchange occurs in various tissues, but is particularly vital in the organs such as the intestines, where nutrients are absorbed from digested food, and in the lungs, where gas exchange occurs.