How is water different from other nutrients?

• A. It provides your body with energy.
• B. It transports oxygen around your body.
• C. It is a single substance.
• D. It helps clot your blood.

Answer: (C)

Water is a pure substance—a single chemical compound (H2O). That sets it apart from other nutrients because it has no calories and isn’t a source of energy. Water’s role is to hydrate, support digestion and circulation, and act as a solvent, but it doesn’t transport oxygen by itself (oxygen is carried in the blood by hemoglobin in red blood cells) and it doesn’t directly cause blood to clot (clotting involves platelets and clotting proteins). So, the defining point is that water is a single, pure substance.