Collagen is the main structural protein in the extracellular space in the various connective tissues in animal bodies. As the main component of connective tissue, it is the most abundant protein in mammals, making up from 25% to 35% of the whole-body protein content. Collagen consists of amino acids wound together to form triple-helices to form of elongated fibrils. It is mostly found in fibrous tissues such as tendons, ligaments and skin.
Depending upon the degree of mineralization, collagen tissues may be rigid (bone), compliant (tendon), or have a gradient from rigid to compliant (cartilage). It is also abundant in corneas, cartilage, bones, blood vessels, the gut, intervertebral discs, and the dentin in teeth. In muscle tissue, it serves as a major component of the endomysium. Collagen constitutes one to two percent of muscle tissue, and accounts for 6% of the weight of strong, tendinous muscles. The fibroblast is the most common cell that creates collagen. Gelatin, which is used in food and industry, is collagen that has been irreversibly hydrolyzed. Collagen also has many medical uses in treating complications of the bones and skin.
When hydrolyzed, collagen is reduced to small peptides which can be ingested in the form of dietary supplement or functional foods and beverages with intent to aid joint and bone health and enhance skin health.
Hydrolyzed collagen has a much smaller molecular weight in comparison to native collagen or gelatin, study suggests that more than 90% of hydrolyzed collagen is digested and available as small peptides in the blood stream within one hour. From the blood the peptides (containing hydroxyproline) are transported into the target tissues, e.g. skin, bones and cartilage, where the peptides act as building blocks for local cells and help boost the production of new collagen fibers.
Uses of collagen
The collagenous cardiac skeleton which includes the four heart valve rings, is histologically, elastically and uniquely bound to cardiac muscle. The cardiac skeleton also includes the separating septa of the heart chambers – the interventricular septum and the atrioventricular septum. Collagen contribution to the measure of cardiac performancesummarily represents a continuous torsional force opposed to the fluid mechanics of blood pressure emitted from the heart. The collagenous structure that divides the upper chambers of the heart from the lower chambers is an impermeable membrane that excludes both blood and electrical impulses through typical physiological means. With support from collagen, atrial fibrillation should never deteriorate to ventricular fibrillation. Collagen is layered in variable densities with cardiac muscle mass. The mass, distribution, age and density of collagen all contribute to the compliance required to move blood back and forth. Individual cardiac valvular leaflets are folded into shape by specialized collagen under variable pressure. Gradual calcium deposition within collagen occurs as a natural function of aging. Calcified points within collagen matrices show contrast in a moving display of blood and muscle, enabling methods of cardiac imaging technology to arrive at ratios essentially stating blood in (cardiac input) and blood out (cardiac output). Pathology of the collagen underpinning of the heart is understood within the category of connective tissue disease.
Collagen has been widely used in cosmetic surgery, as a healing aid for burn patients for reconstruction of bone and a wide variety of dental, orthopedic, and surgical purposes. Both human and bovine collagen is widely used as dermal fillers for treatment of wrinkles and skin aging. Some points of interest are:
- When used cosmetically, there is a chance of allergic reactions causing prolonged redness; however, this can be virtually eliminated by simple and inconspicuous patch testing prior to cosmetic use.
- Most medical collagen is derived from young beef cattle (bovine) from certified BSE-free animals. Most manufacturers use donor animals from either “closed herds”, or from countries which have never had a reported case of BSE such as Australia, Brazil, and New Zealand.
As the skeleton forms the structure of the body, it is vital that it maintains its strength, even after breaks and injuries. Collagen is used in bone grafting as it has a triple helical structure, making it a very strong molecule. It is ideal for use in bones, as it does not compromise the structural integrity of the skeleton. The triple helical structure of collagen prevents it from being broken down by enzymes, it enables adhesiveness of cells and it is important for the proper assembly of the extracellular matrix.
Collagen scaffolds are used in tissue regeneration, whether in sponges, thin sheets, or gels. Collagen has the correct properties for tissue regeneration such as pore structure, permeability, hydrophilicity and it is stable in vivo. Collagen scaffolds are also ideal for the deposition of cells, such as osteoblastsand fibroblasts and once inserted, growth is able to continue as normal in the tissue.
Reconstructive surgical uses
Sounds crazy, but adding powdered connective tissue from cows and fish to your morning coffee, smoothies, oatmeal, or juice is suddenly supertrendy among the clean eating crowd. What gives? We’re talking about collagen powder—the hot new “it” supplement that proponents say not only delivers a wallop of protein, but also soothes achy joints, improves gut health, and reduces the appearance of wrinkles.
So what’s the deal with this tasteless powder? As someone paranoid about premature aging (was that wrinkle there last week?), plagued by sporadic bouts of gastrointestinal distress, and with a set of knees that snap, crackle, and pop like an octogenarian, I needed to find out if this stuff was legit. First step: Do the research. Second step: Give it a whirl.
Initial impression: The science is promising. In one recent study, women who took a collagen supplement daily experienced a 20% reduction in wrinkle depth around their eyes after 8 weeks. Other research finds that daily supplementation can ease osteoarthritis-related knee pain (score!), which makes sense, as collagen provides high levels of the amino acids used to build bone and joint tissue.
And although there aren’t studies on collagen’s effect on gut health yet, there’s probably something to it, says Laura Schoenfeld, RD, holistic nutritionist at Ancestralize Me, noting that collagen’s amino acids may also help prevent intestinal permeability (i.e., leaky gut)—a condition linked to a host of and autoimmune diseases like MS and celiac disease. (Here are 4 surprising foods that may be messing with you gut.)
Alright, that’s all good, but now it’s time to try it for myself. Here’s what happened after I started adding 2 tablespoons of collagen powder to my morning coffee or smoothie for a month.