Vitamin C is important to all animals, including humans, because it is vital to the production of collagen. Vitamin C is also important because it helps protect the fat-soluble vitamin A and vitamin E as well as fatty acids from oxidation. Vitamin C prevents and cures the disease scurvy, and can be beneficial in the treatment of iron deficiency anemia.
Collagen is the most ubiquitous substance in the body because it is the most abundant of the fibers contained in connective tissue. Connective tissue gives our body form and supports our organs. To give you an idea of how important collagen is, here is a list of the five types of collagen, and where they are used in the body.
- Type 1 - Connective tissue of skin, bone, teeth, tendons, ligaments, fascia, organ capsules
- Type 2 - Cartilage
- Type 3 - Connective tissue of our organs (liver, spleen, kidneys, etc.)
- Type 4, 5 - The separating layer between epithelial and endothelial cells as well as between skeletal or smooth muscle cells (basal lamina), kidney glomeruli, lens capsule, and Schwann and glial cells of the nervous system.
As you can see, collagen is everywhere in the body, and vitamin C plays a role in the formation of collagen. So, how is vitamin C involved in collagen synthesis?
When collagen is produced, there is a complex series of events, some occurring inside of the cell, and some outside of the cell. Vitamin C is active inside of the cell, where it hydroxylates (adds hydrogen and oxygen) to two amino acids: proline and lysine. This helps form a precursor molecule called procollagen that is later packaged and modified into collagen outside of the cell. Without vitamin C, collagen formation is disrupted, causing a wide variety of problems throughout the body. (see How Cells Work for more information about the biochemistry of cells.)