Collagen supplements have become a hot commodity for gut health enthusiasts, especially in the last decade. But not all collagen is created equal when it comes to gut health or leaky gut repair.
In this article I’ll share a round-up of the best collagen for gut health and leaky gut, based on my first-hand experiences and expertise as an integrative, holistic, functional gut health dietitian (and as a former IBS sufferer).
- This article is intended to be informative and educational. This is not medical nutrition advice! Make sure to consult a qualified doctor and a gut health nutrition expert for individualized care if you’re navigating digestive issues of any kind.
- One size never fits all! What has worked for others still may not work for you, since everybody is unique.
- No single food or supplement of any kind as a stand-alone intervention should ever replace a balanced diet or be treated as a “be-all-end-all” solution or quick-fix to any health issue.
Affiliate disclosure: This article contains some affiliate links* for products that meet my high standards as a holistic registered dietitian. I only recommend and endorse products that I love and use personally. As an Amazon Associate, if you make a purchase using any of my affiliate links, I will make a small commission at no extra cost to you. 🙂
Okay, now let’s dive in!
Table of Contents
First things first: what is collagen?
Collagen is a type of protein made up of amino acids (building blocks of protein).
From a physiological standpoint, collagen is the most abundant protein in the body (1) – not just in humans, but in many types of animals too. Collagen is a primary matrix for skin, bones, tendons and ligaments.
In the health and wellness industry (and for the context of this article), collagen has evolved into a type of “functional food” – aka a food or nutraceutical supplement which offers health benefits beyond general nutrition (2) because of the benefits it has to offer!
Collagen in the body
While there are said to be 28 different types of collagen existing in nature, most of the collagen types found in the body and in our supplement industry are type I, II, III or IV, with type I making up close to 90% of collagen in the human body in that it forms the basis of connective tissue. (1)
Collagen in supplements
In the supplement industry, you’ve likely seen various types of collagen powders and pills, some for topical use and other brands meant for internal use. But it’s important to keep in mind, not all collagen supplements are created equal!
For example, some collagen is sourced from animals such as bovine (cows), porcine (pigs) or poultry (chickens/turkey), while other collagen supplements are marine-based or vegan.
The collagen most often taken for gut health purposes is collagen peptides (or hydrolyzed collagen).
What is the gut?
When you hear someone refer to the “gut,” they’re not just talking about your stomach! Your gut encompasses your entire digestive tract or “gastrointestinal tract” which begins in your mouth, and also includes the throat, esophagus, stomach, intestines, colon, rectum and anus.
Research from a 2014 study in the Scandinavian journal of gastroenterology established that the surface area of an adult’s gut is actually big enough to cover about half of a badminton court! (5)
The gut is not considered to be inside the body, but rather a mucosal barrier (much like the skin) which serves as a boundary in charge of what can enter our bloodstream (inside the body) versus what must stay out. The gut is sort of like the inside of a donut hole, if that makes sense!
The gut (alongside the liver, kidneys and skin) also serves as a primary detoxification organ responsible for digesting and absorbing nutrients from food while eliminating waste.
Why care about gut health?
Aside from serving as a powerful selective gatekeeper, taking what we need and leaving the rest (when it comes to foods and chemicals), your gut is also majorly synced up with pretty much every other aspect of health in one way or another.
(You may or may not be familiar with ancient philosopher and doctor Hippocrates’s famous quote, “All disease begins in the gut!”)
Your gut and your immune system
It’s been well-established by researchers nowadays that about 70% of the immune system is synced with the gut. This branch of the immune system is often referred to as “Gut-Associated Lymphoid Tissue” (or GALT for short). (6, 7)
That said, it’s no surprise that so many people with autoimmune disorders and allergies are also found to have an imbalanced microbiome (aka “dysbiosis”) and a subsequently compromised gut barrier (aka “leaky gut” or “intestinal hyperpermeability”). (6, 8)
To say that a healthy gut is fundamental to maintaining a healthy, balanced, resilient immune system is an understatement!
The gut-brain axis
You may or may not have heard the gut referred to as the “second brain” – and that’s for good reason! Much like the immune system, research has also uncovered that your gut is intimately connected with your central nervous system. In fact, the gut has its own special network of nerves, referred to as the “enteric nervous system!” (9)
- Fun fact: Did you know there are more neurons in the gut than in the entire spinal cord?!
- Over 90% of the neurotransmitter serotonin (5-hydroxytryptamine or 5-HT) receptors are also located within the enteric nervous system (10, 11).
All of that said, it should come as no surprise that a healthy gut is one of the secret keys to feeling calmer and happier (aka less anxious and less depressed) more often!
The gut-skin axis: as within, so without
“As within, so without…” – Paracelsus
This is a famous saying according to Paraelsus, an ancient medical philosopher and alchemist. While there are lots of different directions an interpretation could go, one way this rings true is in the realm of the gut (within) and the skin (without).
Of course, in some ways, the gut and the skin are two completely different organs – but in certain other ways, two are actually pretty parallel! Your gut is to your skin as “yin” is to “yang.” In other words, the gut is the inner version of the “outer” (skin). They both serve as a barrier between the inside of our body and the outside world!
Your gut and your skin are also the two primary “homes” of the human microbiome (ecosystem of microbes which live in and on us, impacting virtually every aspect of health).
The intimate gut-skin connection may explain why both the gut and the skin benefit from collagen supplementation.
Enter… the multitude of potential collagen health benefits!
Health benefits of collagen, according to science
From a general health and wellness standpoint, there are quite a few great reasons so many people are adding collagen supplements into their routine!
Supplementing with collagen (mostly type I for skin, muscles and gut, or type II for joints) has been shown in research studies to provide the following benefits:
- Improved skin elasticity & skin regeneration (14, 15, 16, 17)
- Faster wound healing (such as in cases of ulcers and burns) (14)
- Healthier joints and reduced joint pain in cases of osteoarthritis & rheumatoid arthritis (14, 17, 18, 19)
- Improved muscle strength/muscle mass in cases of sarcopenia (muscle wasting in the elderly) (14)
- May improve bone density (20)
- May support healthier intestinal permeability (21, 22, 23)
- Can help improve gastroesophageal reflux disease in some cases (14)
- May alter the gut microbiome in ways that benefit the immune system (15)
- May reduce bloating and mild digestive distress (24)
What’s the best type of collagen for gut health and leaky gut?
While research is suggesting that collagen capsules (of type II cartilage collagen) are most effective and user-friendly for people taking collagen for joint health, I’ve found both anecdotally and from research that taking type I collagen (peptides or hydrolysate) in powder form seems to be best for people looking to support a healthy intestinal barrier.
Are all collagen peptides created equal?
Just like all hamburgers are not the same, all collagen peptides are most definitely not created equal!
Below are some of my favorite brands of collagen peptides (in no particular order). They’re all 100% grass-fed, non-GMO, free of glyphosate (a broad-spectrum herbicide found to interfere with nutrient absorption) and third-party tested.
(Side note: I understand this stuff gets expensive! That said, if you’d like to get a lifetime discount of 15% off these products and lots of other high quality supplements, I invite you to join my online dispensary where you can get discounted practitioner-approved supplements shipped to your door in just 3-6 business days, on demand. Click on the FullScript button below to get started.)
How to take collagen peptides
If you’re taking plain, unflavored collagen peptides, they’re pretty versatile and relatively tasteless when properly blended or incorporated into your favorite beverage or recipe!
Here are a few of my favorite ways to take collagen peptides:
- Stir a scoop of plain or vanilla peptides to your morning coffee or tea
- Dissolve a scoop of collagen peptides into oatmeal or overnight oats
- Blend it into your favorite smoothie recipe for extra protein
How much collagen is good for gut health?
In the study from May 2022, about 20 grams per day of collagen peptides for 6 weeks was deemed a clinically effective dose. (24)
According to a Nutrients study from 2019, if collagen is well tolerated from a gut health standpoint, and you meet criteria as someone who can benefit from collagen peptides supplementation, the most effective amounts of functional collagen peptides are about 2.5 to 15 g per day. (25)
(In real life, the above recommendations translate to a range of about 1 teaspoon up to 2 scoops of collagen peptides powder per day, depending on the amount of grams of collagen protein per scoop serving size.)
When in doubt, read the label to verify the serving size and number of grams of collagen per serving. And of course, consult with your functional nutrition practitioner as needed! 😉
The dark side of collagen: side-effects and contraindications
As a quick reminder, there’s no “magic bullet” when it comes to food and health – and collagen is not for everyone! I’ve found in my clinic that not everyone with digestive issues will benefit from collagen. In fact, sometimes it can do more harm than good.
Some common side-effects and contraindications of collagen supplements include:
- Glutamine intolerance
- Tryptophan deficiency
- Food allergy/sensitivity
- Ammonia overload
- May increase risk of kidney stones
- High in protein (too much isn’t good for kidney disease)
(Read more about the contraindications of collagen for leaky gut here.)
So, what’s the best collagen for gut health? (The final verdict)
Not all collagen supplements are created equal!
When it comes to supporting your gut health, opt for type I (collagen peptides) and make sure you’re choosing a product that is organic, non-GMO, glyphosphate-free, 100% grass-fed (if animal-derived) and third-party tested.
- More is not always better! Even in cases of “superfoods” and functional foods, too much of a good thing becomes harmful.
But if you’re dealing with any of the following:
- Diarrhea-predominant IBS (“IBS-D”)
- Inflammatory bowel disease (IBD)
- Kidney disease
- Kidney stones
- Major depressive disorder
- Adverse food reactions
…you should err on the side of caution, and hold off on trying collagen until further notice!
Either way, please make sure to first consult your treatment team (specifically your doctor and dietitian) before trying collagen or dabbling in any new supplement that impacts your health, if you’re navigating a medical condition of any kind. 😉
Additional resources and next steps
If you’d like to learn more about how to improve your gut health via my holistic, evidence-based, mutli-dimensional approach, I invite you to check the following articles:
- What is “Leaky Gut”, and How Do You Know if You Have It?
- Collagen for Leaky Gut: Is It Legit?
- The Low-Down on L-Glutamine for Leaky Gut Repair
- Bitter Herbs for Digestion: What, Why, When, andHow to Get Started
- Does Green Tea Help With Digestion?
And/or, please feel free to check out and enroll in my Complete Gut Repair Roadmap online course!