Collagen is a structural protein that acts as a building block for your bones, teeth, muscles, skin, joints and connective tissues. It can be thought of as a sort of structural glue which holds your body together. It builds our skin, connective tissue and bones but cannot be absorbed through our diet in its full form.
The collagen protein is made up primarily of three amino acids — proline, hydroxyproline and glycine — that form a long chain in a triple helix structure. This twisted triple helix structure gives collagen its unique functional properties including strength and elasticity, and makes it the most important structural protein in the body.
It is the most abundant protein in the body, making up around 30% of total protein content. Around 75% of our skin is made up from collagen protein, while 85% of our tendons and around 90% of our bone mass comes from collagen providing a structural framework.
As the most abundant protein in the body, collagen not only holds the body together but is also key to repairs. However, as we age, our body’s natural collagen production decreases, which is one reason we begin to see visual signs of aging such as sagging skin and wrinkles.
The collagen found in supplements and health products can come from a variety of sources, and can come in many forms, including bovine collagen, chicken collagen, marine collagen, and even plant-based alternatives.
There are at least 28 different types of collagen. Types I, II and III form the bulk — between 80% to 90% — of the collagen in your body. Types I and III provide structure to the skin, muscles and ligaments, while type II is found in cartilage and the eye. Type 1 collagen and Type 3 collagen are usually grouped together because they are the most abundant and have similar bodily functions.
Type I collagen forms the longest triple helixes. This makes the structure of type I collagen extremely strong and suitable to form strong fiber structures that can be stretched without breaking. These elastic structures provide support and flexibility to our body. Type I collagen makes up more than 90% of our organic bone mass, as well as making up a major part of our skin, tendons and ligaments.
You can find type II collagen in hollow organs and your artery walls. Both type I and type III can be sourced from bovine collagen. Type I can also be sourced from marine collagen, unlike type III.
Type II collagen is the collagen form present in cartilage, and makes up around 50% to 60% of all cartilage protein.
It occurs in a natural matrix with glycosaminoglycans (GAGs). While type II collagen provides strength and elasticity to the tissue, the GAGs lubricate the cartilage, together providing the perfect matrix to absorb shock and bear stress. Type II collagen is generally sourced from chicken.