The Collagen Users Manual

No More Achy Joints, Saggy Skin, or Leaky Gut

The Collagen Users Manual
Categorized under Eating

It’s mea culpa time. Here goes: I used to be one of those meatheads that maligned collagen.

“Why Mongo eat collagen? Collagen not grow muscle like slab of ox that Mongo eat for breakfast.”

Back then I might have argued that collagen lacks certain essential amino acids, that it was an “incomplete” protein, and even the amino acids it does contain are in too short a supply to build muscle.

I also use to repeatedly point out that protein bar companies often jam collagen into their products (mostly for taste and texture) but then include it, kind of disingenuously, in the grams of protein advertised on the label, but I now regard that as a misdemeanor supplement crime instead of a capital one.

So yeah, I’ve done an about face in regards to collagen. The truth is, I think collagen as a supplement is hot shit right now, not for any muscle building properties, but for a host of other reasons, chief among them the following:

  • Restoring lost collagen in ligaments, tendons, cartilage, and skin.
  • Reducing joint pain.
  • Potentially speeding up wound healing.
  • Potentially helping to heal damaged digestive tracts and leaky guts.
  • Sparing protein. (Collagen lacks certain essential amino acids and sufficient amounts of others, making it an incomplete protein. Even so, it can still augment your total amino acid intake and thereby help facilitate muscle growth.)

What Exactly is Collagen?

Collagen is a family of proteins that forms the “cabling” in ligaments, tendons, cartilage, and skin. The protein contains 20 amino acids and chief among them are three specific ones: glycine, proline, and hydroxproline.

These three amino acids form part of three-dimensional triple helixes that generally consists of two identical chains and a third chain that’s slightly different in chemical composition.

For instance, typical amino acid sequences in collagen are glycine-proline-x and glycine-x-hydroxyproline, where “x” is any amino acid other than glycine, proline, or hydroxyproline.

All told, these collagen molecules constitute about 33% of all protein in the body.

Normally, humans make their own collagen, but that super power diminishes as we grow older. Excess stress, sunlight, or sugar can also muck up production, eventually leading to achy joints and the “bag of bones” physio-type that can often be seen nursing their cups of coffee in McDonald’s restaurants on weekday mornings.


Are There Different Types of Collagen?

Depending on how nitpicky you get about it, there are between 16 and 28 different types of collagen in the human body, but probably only five to seven of them are important to human health. Of these, just three of them make up the vast majority of the collagen found in the body.

These three are known simply as type I, type II, and type III collagen. Of these three, type I is the most prominent, forming over 80% of the total collagen in the immature human body and over 90% in mature articular cartilage.

Generally speaking, each type has the following functions:

Type I Collagen

This form of collagen is most closely associated with improving skin elasticity and hydration. It also plays a role in the health of your nails and the thickness and tensile strength of your hair.

Type II Collagen

This form is found in tendons, ligaments, and cartilage.

Type III Collagen

This form is native to your muscles, blood vessels, intestines, and uterus. It, like Type I, also plays a role in skin elasticity.

There are a couple of other collagens that might be important to human health, too. They’re known as type V and type X. The former coexists with type II, supporting many of the same functions, while the latter helps form cell surfaces, hair, and a pregnant woman’s placenta.

You probably don’t need to overly concern yourself with these last two.

Why Not Just Eat a Lot of Regular Protein?

I used to think that eating another animal’s collagen to make more of your own collagen was a ridiculous notion. My thinking was that proteins, regardless of the type, would all be broken down by the digestive system into their constituent amino acids and then used by the body to make the proteins it needs.

For example, the body would take amino acids from the whey or casein or chicken salad you ate earlier and use them to form whatever tissues it needed, in this case collagen.

While this is of course true, it also seems that specific collagen peptides – small chains of amino acids that pass into the blood stream through the digestive system – are able to initiate collagen production more efficiently than forcing the body to “forage” for individual amino acids.

Further, oral ingestion of some of these collagen di- and tripepties, e.g. proline hydroxyproline, can stimulate fibroblasts to produce hyaluronic acid, which is the same stuff often injected by skincare specialists as a cosmetic filler.

Where Do Collagen Supplements Come From?

Manufacturing wise, there are two main sources of collagen: cows and fish, otherwise known as bovine collagen and marine collagen. Marine-sourced collagen is rich in type I while bovine collagen is particularly rich in I and III. Collagen from chicken sternums is also common and it’s rich in type II collagen.

But there’s another important distinction you need to be aware of: Collagen supplements are not only classified as type I, type II, and type III, etc., but also as undenatured (“native”) collagen and hydrolyzed collagen.

Type II collagen is undenatured and retains the three-dimensional structure I described earlier. It allegedly works by an immune-mediated process and causes the body to produce substances that fight pain and swelling, thus enabling far smaller dosages to be used.

The other types of collagen, however, are hydrolyzed. Manufacturers employ digestive enzymes to cut the triple helix molecules into smaller, more easily assimilated pieces. These peptides and amino acids are then used as building blocks to construct more cartilage. Larger dosages are typically required.


What Do the Studies Show?

  • 57 men were randomly and double-blindedly divided into a collagen peptide group and a placebo group. Each was given 15 grams of hydrolyzed collagen or placebo each day for 12 weeks. All subjects engaged in the same training program.
    The collagen group showed a significant increase in fat-free mass while the placebo group showed a significant increase in body fat. However, both groups showed equal levels of muscle fiber hypertrophy, causing the researchers to postulate that the collagen group’s increase in fat-free mass was the result of thickened connective tissues, courtesy of the collagen.
  • 40 grams of hydrolyzed collagen supplementation a day for 4 months improved knee range-of-motion from 73.2 degrees to 81 degrees while the placebo group showed no improvement in range of motion.
  • Taking 10 mg. of hydrolyzed collagen every day for 24 weeks reduced knee pain associated with osteoarthritis.
  • 40 mg. of undenatured collagen a day worked better in improving joint health than a combo of 1500 mg. of glucosamine and 1200 mg. of chondroitin.
  • Aussies recruited a group of 18 runners with injured Achilles tendons and divided them into two groups. Both groups did a series of eccentric exercises for their injured tendons twice a day for six months.

For the first three months, one group also received a daily 2.5-gram dose of hydrolyzed collagen while the other group got a placebo. The collagen group healed much faster.

How Much Should I Take?

Type II collagen supplements typically come in undenatured form and are available as capsules. Type I and type III collagen supplements, however, typically come in hydrolyzed form and are available in the same sort of tubs or pouches that protein powders come in.

I recommend buying a type that is a blend of types I, II, and III and if it happens to also contain types V and X, fine. While suggested dosages are all over the place, 20 grams a day of a collagen blend seems to be a pretty good sweet spot (unless you employ the efficiency-enhancing hacks I explain a few paragraphs down, in which case 10 grams a day would suffice).

You could, however, choose to go the gelatin route instead. The mass-produced substance is almost pure collagen, and given that it’s made from the skin and bones of cattle or pigs, it consists of type I and type III collagen. The raw gelatin powder contains virtually the same amount of collagen as a collagen supplement, so they’re virtually interchangeable.

Here’s How to Supercharge Your Collagen

Here’s where I confuse things a little. Remember how earlier I implied there was something magical about ingesting collagen, something that couldn’t be duplicated by eating whole, non-collagen proteins?

Well, it may be that most of collagen’s magic comes from its high concentration of glycine, proline, hydroxyproline, and lysine. If that’s true, could you reap the benefits of collagen by just eating higher concentrations of those amino acids instead of collagen? Maybe.

Spanish scientists decided to figure out the comparative contributions of each in synthesizing cartilage. To do so, they cultured bovine chondrocytes using a large range of concentrations of these amino acids.

Both proline and lysine enhanced the synthesis of collagen, but the effects decayed before reaching 1.0 mM (a measure of the concentration of a chemical in solution). Glycine also enhanced the synthesis of collagen, but the effects didn’t decay before reaching a 1.0 mM concentration. In fact, glycine continued to increase collagen synthesis by 60-75%.

The researchers involved in that study concluded the following:

“Increasing glycine in the diet may well be a strategy for helping cartilage regeneration by enhancing collagen resynthesis, which could contribute to the treatment and prevention of osteoarthritis.”

Does that mean I think you should ditch the collagen and just supplement with glycine? One study isn’t enough to cause me to adjust course just yet. However, I do think the evidence merits adding a couple of daily grams of glycine to your collagen intake.

One More Thing….

I don’t want to biohack this whole thing to death, but there’s one more easy thing you can do to get the most out of your collagen or collagen/glycine supplementation.

Scientists found that adding just 48 mg. of vitamin C to a gelatin mix (which, as you recall, is almost pure collagen) increased circulating glycine, proline, hydroxyproline, and hydroxylysine, peaking 1 hour after the supplement was given.

In fact, subjects who took 15 grams of gelatin/vitamin C 1 hour before exercise “showed double the amino-terminal propeptide of collagen 1 in their blood, indicating increased collagen synthesis.”

Again, it’s just one study, but it has the smell of truth and it’s an easy hack.

Final Recommendations

I’ve thrown a lot at you, but here are my current, best, collagen recommendations:

  1. Take 10 grams a day of a collagen blend that contains type I, type II, and type III collagen. If it also contains type V and X, all the better.
  2. Augment that 10 grams of collagen with at least 2 grams of supplemental glycine to increase collagen production even further.
  3. Lastly, take a small hit of vitamin C with your collagen and glycine to make it even more potent. You only need a small amount – 15 grams – but since most vitamin C supplements come in 250 mg. or 500 mg. tablets, go ahead and use that amount rather than X-Acto-ing up the tablets into 15 mg. bits.
  4. If, however, you don’t want to use these last two hacks to enhance your collagen “experience,” just stick with straight collagen powder but increase the daily dosage to 20 grams a day instead of 10.


  1. Praet, Stephan, et al. “Oral Supplementation of Specific Collagen Peptides Combined with Calf-Strengthening Exercises Enhances Function and Reduces Pain in Achilles Tendinopathy Patients,” Nutrients 2019, 11(1).
  2. James P. Lugo, Zainulabedin M. Saiyed, Nancy E. Lane, “Efficacy and tolerability of an undenatured type II collagen supplement in modulating knee osteoarthritis symptoms: a multicenter randomized, double-blind, placebo-controlled study.” Nutrition Journal, 29 January 2016.
  3. de Paz-Lugo P1,2, Lupiáñez JA3, Meléndez-Hevia E4, “High glycine concentration increases collagen synthesis by articular chondrocytes in vitro: acute glycine deficiency could be an important cause of osteoarthritis,” Amino Acids, 2018 Jul 13.
  4. D.C. Crowley, et al. “Safety and efficacy of undenatured type II collagen in the treatment of osteoarthritis of the knee: a clinical trial,” Int. Journal of Med Sciences, 2009; Volume 6, pp. 312-321.
  5. Shaw G, Lee-Barthel A, Ross ML, Wang B4, Baar K. “Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis,” Am J Clin Nutr. 2017 Jan;105(1):136-143.

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