The Functions of Proteins in the Human Body

Chemical messengers for hormones

Some proteins act as chemical messengers, regulating body processes. (Not all hormones are proteins.)

Provide essential energy

Protein can be used to provide calories (four calories per gram) to help meet the body's energy needs.

Acid/Base balance

Proteins act as buffers to maintain the normal acid and base concentrations in body fluids.

Provide antibodies

Proteins assist the body in maintaining its resistance to disease by acting against foreign disease-causing substances.

Provide enzymes

Proteins facilitate numerous chemical reactions in the body; all enzymes are proteins.

Form essential body structures

Proteins form vital parts of most body structures such as skin, nails, hair, membranes, muscles, teeth, bones, organs, ligaments, and tendons.

Facilitate fluid balance

Proteins help regulate the quantity of fluids in body compartments.

Transportation of substances throughout the body

Proteins move needed nutrients and other substances into and out of cells and around the body.

Growth and maintenance

Proteins provide building materials - amino acids - for growth, replacement and repair of body tissues.