Of all the topics I write about, collagen garners perhaps the most questions. Not that I’m complaining. I’m happy to wax on about the benefits of collagen all day long. I’ve said before that I consider collagen the fourth macronutrient, and it doesn’t get the recognition it deserves. The more people who get turned on to it the better, as far as I’m concerned.

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Collagen used to be abundant in the human diet, back in the days before we decided that gnawing on bones, eating the stringy bits, and boiling down the skin was “icky.” We lost a significant source of critical amino acids when we started eating the lean muscle and discarding the rest, and we’re less hearty as a species because of it. And yes, Primal Kitchen produces a line of collagen products, but that’s not why I harp on it so much. The opposite, actually. I started making collagen supplements because I think collagen should be on everyone’s radar, not the other way around. Frankly, I don’t even consider collagen “supplemental.” It’s food.

Today I’m rapid-fire tackling twenty questions that have come in recently. A bunch more remain in the queue, so I’m already planning a follow-up post. If there’s something else you’d like me to cover, leave your question in the comments section below.

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Collagen Q&A

What is collagen made of? Where does it come from?

Collagen is a type of protein. Collagen peptide supplements contain specific amino acids you need in order to synthesize the more than two dozen types of collagen found in the human body. Collagen supplements are derived mostly from the skin, bones, and connective tissues of cows, pigs, chicken, and fish.

What does collagen do? Why is it important?

Collagen is the most abundant protein in the human body. It’s integral to the structure of tendons, ligaments, fascia, bones, skin, blood vessels, hair, nails, and even your eyeballs. Insufficient collagen leads to pain, weakness, joint issues, and inability to heal wounds and other injuries.

What is collagen good for? Why should I consider taking collagen peptides?

Collagen peptides provide amino acid “building blocks” that your body uses to produce and maintain collagen protein, including in hair and nails. In scientific studies, collagen supplementation alleviates joint pain,¹ speeds wound healing,² reduces wrinkles and promotes skin elasticity.³ Glycine in collagen improves sleep quality⁴ and gut health.⁵

What is the difference between hydrolyzed collagen and collagen peptides?

There is no meaningful difference. Collagen proteins are long chains of amino acids. The process of hydrolysis breaks them down into peptides, which are just shorter chains of amino acids. Collagen supplements are variously labeled as “hydrolyzed collagen” or “collagen peptides,” but they’re the same.

Who needs collagen supplements?

In my opinion, pretty much everyone could benefit. Most people don’t eat bones, skin, and connective tissues—the parts of animals that contain collagen. That means they don’t get the amino acids (especially hydroxyproline, glycine, and proline) that are found in collagen but not much in muscle meat.

How much collagen should I take per day?

There is no RDA for collagen, and to my knowledge, no studies have established optimal dosing guidelines. You might need more or less depending on your dietary intake. To be safe, it’s always a good idea to follow the dosage instructions on your collagen supplement of choice.

Can you take too much collagen peptides?

Many things in nature follow a J-shaped curve—too much or too little are both bad. The same might be true for collagen supplements, but unfortunately, there’s no indication of what would constitute “too much.” There’s also no evidence that collagen toxicity is a concern if you following dosing guidelines.

I’ve seen Mark suggest take 30 grams of collagen per day. Lots of serving sizes are 20 grams. Where did he get the 30 grams per day?

First, 20 grams isn’t wrong. I arrived at 30 by working backwards. Your body needs 16 grams of glycine, minimally, for basic metabolic processes. Most people get around 6 grams from diet and endogenous synthesis, leaving them 10 grams shy. Collagen is roughly 1/3 glycine, hence 30 grams.

Can I take collagen peptides every day? Should I?

I see no reason why not. You can consume meat and bone broth every day. Collagen peptides are just amino acids in a different form, albeit more concentrated. The only caveat is that I wouldn’t supplement if you’re getting plenty of collagen in your diet. There’s no need.

Do I have to supplement collagen if I’m getting adequate protein?

It depends. By “adequate protein,” do you mean that you are tracking your food in a macronutrient app and hitting your protein target? That’s great… but did it all come from muscle meat? What about skin, connective tissue, bone broth? If you’re not eating nose-to-tail, you probably want to supplement.

Collagen side effects? Are there risks associated with taking collagen peptides?

Collagen peptides are generally regarded as safe. In studies, the main complaint associated with collagen supplementation seems to be gastrointestinal issues. At least in one review, adverse effects were no different than in control groups.⁶ Of course, stop supplementing if you notice any undesirable side effects.

How do I know if I should adjust the dose?

This is tricky. Collagen isn’t necessarily a fast-acting supplement. I’d say give it at least six or eight weeks to work based on typical study protocols. If you ever experience any issues like gas or a metallic taste in your mouth, try halving your dose.

Should collagen and complete protein (meat or whey) be taken separately?

“Don’t mix protein and collagen” is one of these pieces of advice that circulates around the internet, but I can’t find any evidence that it’s really necessary. I’ll sometimes make a point of separating them just in case it does improve absorption, but I’m not convinced it matters.

What is the best time of day to take collagen? Morning or night? On an empty stomach or with food?

There’s not enough research to say definitively one way or another. Feel free to experiment with different protocols and see if you have a preference. Since the glycine in collagen promotes sleep, it makes sense to take it in the evening if better sleep is your goal.

Does it matter if I mix collagen peptides in hot or cold liquid? Can hot liquid damage collagen peptides?

No, it doesn’t matter. According to one study, collagen starts to become denatured, or degraded, around 570 degrees Fahrenheit (300 degrees Celsius), but it probably isn’t irrevocably altered until closer to 650 degrees Fahrenheit (345 degrees Celsius).⁷ That’s much hotter than any liquid you’d ever consume.

What can I do to enhance the effectiveness of collagen peptides or make them more bioavailable?

Vitamin C and zinc both stimulate collagen synthesis.⁸ I regularly use collagen plus vitamin C as a pre-workout, and I’ve had great success rehabbing tendon issues by combining collagen peptides with 50 mg of vitamin C.⁹ (I don’t routinely supplement zinc because I get plenty from meat and shellfish.)

Are collagen peptides and gelatin interchangeable?

Yes and no. They contain the same amino acids, so they’ll deliver the same collagen building blocks. However, collagen peptides are smaller and probably more easily absorbed. In the kitchen, you can use gelatin—but not collagen peptides—to make gummies or thicken soups, stews, or pan sauces.

What do you think of marine collagen?

Marine collagen, which comes from fish scales, bones, and skin, seems to have similar benefits to collagen derived from mammals. It's a great option for folks who are allergic to bovine collagen. It might even be slightly more bioavailable than bovine collagen. However, it’s also less stable at high temperatures.¹⁰

Are there any good vegan collagen supplements?

Only animals produce collagen, so it can’t be vegan. Scientists have started to genetically engineer vegan “collagen” from yeast and bacteria, but so far, studies haven’t demonstrated that it’s as beneficial as animal-derived collagen. Vegetarians may find collagen supplements made from eggshells to be a suitable compromise.

How does bone broth stack up to collagen peptide supplements? Is one better than the other?

I love bone broth, but if you want to be sure about how much collagen you’re getting, opt for supplements. The amount of collagen in bone broth can vary significantly from batch to batch depending on what you throw in the pot and how long you cook it.

Stay tuned for round 2 soon!

References

https://pubmed.ncbi.nlm.nih.gov/18416885/ ↩
https://pubmed.ncbi.nlm.nih.gov/16557055/ ↩
https://pubmed.ncbi.nlm.nih.gov/24401291/ ↩
https://www.ncbi.nlm.nih.gov/pubmed/22293292 ↩
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5622680/ ↩
https://pubmed.ncbi.nlm.nih.gov/22521757/ ↩
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3127184/ ↩
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6204628/ ↩
https://www.ncbi.nlm.nih.gov/pubmed/27852613 ↩
https://www.ncbi.nlm.nih.gov/pmc/articles/pmc4519503/ ↩

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* This blog reflects my personal views and opinions and isn’t intended as medical advice, but I hope it will be informative and inspiring as you pursue a healthy, fulfilling life.

Collagen Peptides FAQ: Answering 20 Questions…