Collagen is a protein that literally holds the body together. Joints, tendons, skin and bone are high in collagen. We can lose collagen due to age and inflammation.
There are numerous types of collagen with the majority being labeled type I, II or III. Collagen type I is the most common and is distributed in bones, ligaments, tendons, and skin, where it imparts skin’s elasticity and strength. Wrinkles and an aged appearance of the skin is due to collagen degradation. Collagen type II is primarily distributed in cartilage. Collagen type III, which is always found with type I, is most prevalent in skin, blood vessels, and internal organs.
Food sources of collagen, other than supplements, include any meat that contains muscle or connective tissue. Fish, egg whites, spirulina, and bone broth contain collagen. The amount of collagen in bone broth varies.
The body doesn’t absorb collagen molecules in their whole form, but breaks collagen down into the amino acids that make up collagen. The body then uses the necessary amino acids to synthesize its own collagen and other proteins. It is thought that the body can make collagen when needed from any protein source. Vitamin C is needed for collagen synthesis and to keep collagen from degrading. Zinc and sulfur are also important to collagen production. Some experts point out that our bodies decide how to use the amino acids and if collagen will be made or if the protein will go toward some other function like wound healing. So it may be impossible to direct where collagen will be used in the body.
Some research on collagen is promising but still questionable with more large studies (not industry funded) needed. Most research has been done on collagen supplements and not collagen from food and has mostly been funded by industry. It is not clear yet as to if one type of collagen is superior. Most collagen supplements consist of hydrolyzed collagen, which is collagen that is broken down so that it is highly digestible. The amino acid composition is the same in gelatin and collagen but the difference is in bioavailability with gelatin not very bioavailable. Some arthritis studies have looked at un-denatured type II collagen (UC-II), which acts differently. UC-II is collagen that hasn’t been broken down. UC-II stimulates oral tolerance and tempers immune reactions that cause inflammation and joint pain rather than promoting collagen synthesis. Collagen may offer potential for bone health and preventing osteoporosis. A few small human studies indicated that collagen supplementation may help improve bone mass and prevent bone loss, but we need more studies.
If more collagen research indicates collagen supplements are beneficial it is doubtful that collagen alone would be enough. Exercise and overall diet would still be crucial.
Smoking, and sun and pollution exposure can affect collagen integrity. Interestingly, refined sugar molecules bind to collagen fibers and result in the formation of a substance that causes irreversible loss of strength and flexibility in collagen fibers. This has been specifically noted to make skin more prone to sagging. Could it also affect our bones? Just one more reason to limit our refined sugar intake.