Hydrolyzed collagen

Hydrolyzed collagen is a form of collagen. It is also called collagen hydrolysate, collagen peptide, gelatine, gelatine hydrolysate and hydrolyzed gelatine. Hydrolyzed collagen contains a different type of collagen depending upon its source. Hydrolyzed collagen derived from gelatin has primarily collagen type I and III while hydrolyzed collagen made from chicken sternal cartilage contains type II collagen and also coexisting glycosaminoglycans (GAGs) such as hyaluronic acid and chondroitin sulfate.

Production
Hydrolyzed collagen is produced from collagen found in the bones, skin, and connective tissue of animals such as cattle, chicken, fish, horses, pigs, and rabbits. The process of hydrolysis involves breaking down the molecular bonds between individual collagen strands using heat and either acid or alkali solutions. Typically, with skin sourced collagen, hides are put in a lime slurry pit for up to 3 months, loosening collagen bonds; the hides are then washed to remove lime, and the collagen extracted in boiling water. The extracted collagen is evaporator concentrated, desiccated with drum driers, and pulverized.

There are different types of hydrolysis, some are done with either an acid solution (gelatin) or fruit enzymes process. In contrast, hydrolyzed collagen type II sourced from chicken sternal cartilage employs an enzymatic process to break down polypeptide chains to produce low molecular weight collagen type II peptides.

Characteristics
The hydrolysis process results in reducing the collagen proteins of about 300,000 Da into small peptides having an average molecular weight between 2000 and 5000 Da.

Amino acid content
The amino acid content of hydrolyzed collagen type I/III or type II is the same as that its collagen source. Hydrolyzed collagen contains both non-essential and essential amino acids, predominantly glycine, proline and hydroxyproline, which together represent around 50% of the total amino acid content, but lacks or contains very low levels of amino acids such as tryptophan and asparagine.

Nutrition
Glycine and proline concentration is as much as 20 times higher than other food sources of protein. Hydrolyzed collagen contains 8 out of 9 essential amino-acids, including glycine and arginine —two amino-acid precursors necessary for the biosynthesis of creatine. It contains no tryptophan and is deficient in isoleucine, threonine, and methionine.

Digestibility
The bioavailability of hydrolyzed collagen was demonstrated in a 1999 study; mice orally administered 14C hydrolyzed collagen digested and absorbed more than 90% within 6 hours, with measurable accumulation in cartilage and skin. A 2005 study found hydrolyzed collagen absorbed as small peptides in the blood.

Skin Health
A preclinical study investigated the effects of oral ingestion of hydrolyzed collagen, along with vitamin C and glucosamine, suggested that the moisture content of skin, its viscoelastic properties, and smoothness benefit.

A published study reports that the oral intake of hydrolyzed collagen type II (BioCell Collagen) reduces facial aging signs. A human study enrolling 26 female subjects demonstrated that BioCell Collagen was well tolerated with no serious adverse event and led to a significant reduction of skin dryness and wrinkles from baseline. An increase in collagen and blood circulation was also observed. More studies are needed to confirm the observation.

The mechanism of action of ingested hydrolyzed collagen on skin may be the increased density of collagen fibrils and the fibroblasts' density (the fibroblasts being the main cells of the dermis, and those producing collagen). It may be that that the peptides of ingested hydrolyzed collagen have chemotactic properties on fibroblasts or an influence on growth of fibroblasts.

Joint & Bone Health
Clinical studies report that the oral ingestion of hydrolyzed collagen decreases joint pain, those with the most severe symptoms showing the most benefit.

A published study reports that the oral intake of hydrolyzed collagen type II (BioCell Collagen) reduces joint discomfort. A randomized controlled trial (RCT) enrolling 80 subjects demonstrated that BioCell Collagen was well tolerated with no serious adverse event and led to a significant improvement of chronic joint discomfort. More studies need to be performed to confirm the observation.

Other clinical trials have yielded mixed results. Four studies reported benefit with no side effects; however, the studies were not extensive, and all recommended further controlled study. One study found that oral collagen only improved symptoms in a minority of patients and reported nausea as a side effect. Another study reported no improvement in disease activity in patients with rheumatoid arthritis. Another study found that collagen treatment may actually cause an exacerbation of rheumatoid arthritis symptoms.

Beneficial action is likely due to hydrolyzed collagen accumulation in the cartilage and stimulated production of collagen by the chondrocytes, the cells of cartilage.

Several studies have shown that a daily intake of hydrolyzed collagen increases bone mass density. It seems that hydrolyzed collagen peptides stimulated differentiation and osteoblasts activity- the cells that build bone- over that of osteoclasts (cells that destroy bone).

Efficacy assertions
It has been claimed that hydrolyzed collagen may promote lean muscle mass through and the burning of fat rather than carbohydrates and proteins, toning and thickening skin, joint rebuilding, arterial strengthening, increased energy, organ rebuilding, alleviate osteoporosis, as well as lessening the symptoms of arthritis, high blood pressure, bladder weakness, chronic fatigue, shallow breathing, autoimmune, skin problems, and splitting nails.

Safety concerns
Hydrolyzed collagen, like gelatin, is made from animal by-products, including skin, bones, and connective tissue. It is possible that consumption of hydrolyzed collagen risks contraction of Transmissible spongiform encephalopathy.

The U.S. Food and Drug Administration (FDA), with support from the TSE (Transmissible spongiform encephalopathy) Advisory Committee, has since 1997 been monitoring the potential risk of transmitting animal diseases, especially bovine spongiform encephalopathy (BSE). The FDA study concluded: "...steps such as heat, alkaline treatment, and filtration could be effective in reducing the level of contaminating TSE agents; however, scientific evidence is insufficient at this time to demonstrate that these treatments would effectively remove the BSE infectious agent if present in the source material."

Cosmetics
In Cosmetics, hydrolyzed collagen may be found in topical creams, acting as a product texture conditioner, and moisturizer.