Most people take collagen supplements to improve the health of their joints and skin. A lot of athletes use the supplements as a source of protein and to improve the recovery and health of their overused joints. Collagen peptides are utilized in the cosmetic industry to reduce wrinkles, rejuvenate skin, and give you that coveted glow, but did you know that the ingestion of the different types might improve your digestive health and can even affect the probiotic growth of your microbiome?

So What Is Collagen?

Collagen is a naturally occurring protein that is found the most in flesh and connective tissues. Collagen also contains many different amino acids, and most supplements are high in glycine and proline. Glycine is used by the body as an inhibitory neurotransmitter and protects against glutamate hyper-excitability and promotes relaxation and sleep. Glycine also helps improve insulin insensitivity, reduces inflammation, and improves liver function. We use proline to complete protein synthesis, proper metabolism, reduce atherosclerosis, and regulate immune responses. Glycine and proline can both be produced by our body from other amino acids, but only if you take in enough clean protein in your diet. Ingestion of collagen would provide both amino acids and more like glutamine, lysine, and arginine to improve your health.^{1 2 3 4 5 6 7}

These are three types of collagen that you can mainly supplement with:

• Type 1 – most abundant collagen in the human body. It is present in scar tissue, tendons, skin, arterial walls, cornea, surrounds muscle fibers, fibrocartilage, intervertebral disks, and bones and teeth. Its use is important in improving muscle, eye, skin, cardiovascular, bone, wound, and back health.^{8 9}
• Type 2 – found in joint cartilage, intervertebral disks, and the vitreous body of the eye. Its use is important in improving joint, back, and eye health.^{10 11}
• Type 3 – the second most abundant type of collagen in the human body. It is found in the intestinal walls, reticular fibers, uterus, muscles, blood vessels, and combined with type 1. Its use is important in improving digestive, uterine, muscle, and cardiovascular health.^{12 13}

The digestion of collagen begins in the stomach. The first step in digestion consists of the breakdown of collagen to form dipeptides and tripeptides or free amino acids in the stomach. Several proteases (proteases produced by the pancreas, small intestinal brush-border proteases, peptidase) further break down the collagen into amino acids, which some are used in the gastrointestinal tract and the rest enter into systemic circulation. Finally, some of the peptides are fermented by Bifidobacteria and act as a prebiotic, increasing both probiotic colonies and motility.^{14 15}

Here are the recommended collagen types to be used with different health issues:

• Cardiovascular – if you want healthier cardiovascular health a type 1 and 3 supplement and Biocell or alternating ingestion of chicken and beef bone broth should be supplemented.
• Eyes – type 1 and type 2 should be supplemented for proper health.
• Joints – if you are having joint issues a type 2 supplement like Biocell may help improve your joint health. Biocell collagen is a supplement that is made from the hyaline cartilage of chicken sternum. The supplement itself has type 2, hyaluronic acid, and chondroitin sulfate. The body to lubricate joints uses hyaluronic acid. Chondroitin is a chain of alternating sugars that help make up the structure of cartilage. Biocell contains all three and might be the best to improve the health of your joints. Ingestion of chicken bone broth can also be used.
• Intestinal – for intestinal health all three collagen types should be supplemented. A type 1 and 3 supplement and Biocell or alternating ingestion of chicken and beef bone broth.
• Skin – if you want healthier skin a product with type 1 and type 3 or hydrolyzed collagen peptides should be used.
• Spine – for spine health all three types should be supplemented. A type 1 and 3 supplement and Biocell or alternating ingestion of chicken and beef bone broth.
• Uterus – type 3 should be a supplement for proper uterine health.

How Does the Ingestion of Collagen Improve Digestive Health?

Ingesting collagen has many different positive effects on our digestive health. As I wrote earlier, collagen is high in the amino acid glycine which improves digestive health, regulates inflammation, protects the mucosal barrier, and improves enterocyte function in the intestinal tract. It protects against systemic endotoxin damage from leaky gut. Glycine also protects the liver and aids in detoxification and bile acid production. Finally, glycine improves fructose malabsorption.^{16 17 18 19}

Collagen can also be used as a prebiotic to increase Bifidobacteria growth and increase motility. Collagen increases all necessary amino acids to facilitate proper Bifidobacteria growth. The amino acids that are in collagen can be broken down by Bifidobacteria and used for energy and growth just like carbohydrate sourced prebiotics like GOS.²⁰

If you are on a low carb, very low carb, or no carb diet it is paramount that you ingest collagen supplements or beef and chicken bone broth regularly. The ingestion of collagen would help you maintain the integrity of your mucosal barrier, improve mucus membrane health in the entire body, protect microbiome diversity and population, and keep proper energy production by the bacteria in our microbiome.^{21 22}

If you have ulcerative colitis and Crohn’s disease or other forms of MAP overgrowth you might want to avoid bovine sourced supplement and stick with poultry and marine sources. Granted MAP(Mycobacterium avium paratuberculosis) contamination of collagen or bone broth should be very limited, it is still advised for most people to prevent flareups.

Finally, supplements derived from marine sources might be the best in improving leaky gut. Supplements derived from fish has been shown to close the tight junctions of the intestinal tract reducing permeability.²³

How to Increase Collagen Ingestion and Endogenous Synthesis to Improve Health

There are many different ways you can increase collagen intake in your daily life.

You can take type 1, type 2, and type 3 supplements. The supplements I recommend are:

• Type 1: Bulletproof Upgraded Collagen, Great Lakes collagen
• Type 2: Biocell (poultry source), Vital Proteins (beef source)
• Type 3: Ancient Nutrition Bone Broth Collagen
• Collagen peptides: Vital Proteins collagen peptides
• Marine: Seacure, Vital Proteins marine collagen

Ingestion of chicken (type 2) and beef bone broth (type 1 and 3) would also provide collagen to improve your health.

Supplementation of vitamin C and copper (if you are deficient) are both important in encouraging proper endogenous synthesis and utilization of collagen. I suggest if you are using a collagen supplement or increasing it in your diet to take a low dose of 500 mg of ascorbic acid daily to increase the potential of collagen helping your issues. For copper, most people may have elevated unbounded copper in their bodies, that being said ingestion of beef liver once or twice weekly should provide enough ceruloplasmin bonded copper to help improve collagen synthesis and utilization.^{24 25}