This Dr. Axe content is medically reviewed or fact checked to ensure factually accurate information.
With strict editorial sourcing guidelines, we only link to academic research institutions, reputable media sites and, when research is available, medically peer-reviewed studies. Note that the numbers in parentheses (1, 2, etc.) are clickable links to these studies.
The information in our articles is NOT intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice.
This article is based on scientific evidence, written by experts and fact checked by our trained editorial staff. Note that the numbers in parentheses (1, 2, etc.) are clickable links to medically peer-reviewed studies.
Our team includes licensed nutritionists and dietitians, certified health education specialists, as well as certified strength and conditioning specialists, personal trainers and corrective exercise specialists. Our team aims to be not only thorough with its research, but also objective and unbiased.
The information in our articles is NOT intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice.
What Is Collagen? Benefits for Skin, Hair, Joints and More
February 16, 2023
You might recognize it as an ingredient in your favorite skin serums or perhaps noticed it in joint-supporting supplements, but what is collagen? What does collagen do, exactly, and how can you incorporate it into your life?
Collagen is the most abundant protein in our bodies, especially type 1 collagen. It’s found in muscles, bones, skin, blood vessels, digestive system and tendons.
Collagen benefits are so striking because this protein is what helps give our skin strength and elasticity, along with replacing dead skin cells. When it comes to our joints and tendons, in simplest terms, it’s the “glue” that helps hold the body together.
Unfortunately we lose collagen as we age, but certain food sources as well as supplements can help us hold on to as much as possible.
What Is Collagen?
What is collagen made up of? It is often referred to as a “complex protein,” which is not surprising considering it contains a whopping 19 different amino acids .
These include a mix of both nonessential (also called conditional) and essential types. It’s a particularly great source of arginine, glutamine, glycine and proline.
Composed of three chains, collagen protein is wound together in a tight triple helix. Each chain is over 1,400 amino acids long!
Procollagen is the “soluble precursor of collagen formed by fibroblasts and other cells in the process of collagen synthesis.” As explained in the Journal of Supramolecular Structure:
Collagen in most tissues of higher animals and in many tissues of lower animals takes the form of a rope with a high degree of order. Like a rope, which has several levels of coiling, the collagen fibril has four structural levels of which at least three are coils. The polypeptide chain, the molecule, and the microfibril are helical structures; the fibril may consist of parallel or perhaps coiled microfibrils.
In other words, collagen fibrils are what allow the shape of connective tissues to be defined and maintained. The so-called “microfibrillar structure” is what makes up collagen.
Proline and glycine are the primary types of amino acids found in collagen chains. Both proline and glycine aren’t abundant in animal meats, which is where most people eating a “Western diet” get the majority of their protein.
When you’re sick, under a lot of physical or emotional stress, or otherwise unhealthy, your body may not be able to produce enough amino acids on its own. The body then needs help from outside sources, mainly your diet or supplements, to get its fill.
The highest percentages of amino acids found within collagen, along with some of their key benefits, include:
- Proline : Proline makes up almost 15 percent of collagen. Proline and glycine, in particular, play a major role in ensuring your body’s running smoothly. Proline helps protect integrity of blood vessels, improve joint health and has various cardiovascular benefits.
- Glycine : Around one-third of the protein found in collagen is glycine . While size-wise it’s the smallest amino acid, glycine has big effects. To ensure our cells function properly, glycine helps build healthy DNA strands. It also helps form creatine, which promotes healthy muscle growth and boosts energy production during workouts.
- Glutamine : Considered to be one of the most important and abundant nutrients in the body, glutamine is both created within our muscles and also obtained from food sources. Research shows that glutamine has benefits for preventing anxiety, tension, sleep disorders/insomnia, a lack of concentration, poor digestive health, a weakened immune system and low energy. According to a report printed the American Journal of Clinical Nutrition , it’s been shown to have positive effects of production of growth hormone, which can improve aspects of mental health, such as helping with release of GABA that boosts feelings of “inner calm and tranquility.” Nitrogen, created by glutamine in high amounts, also helps with wound healing and prevents muscle wasting and joint pains.
- Arginine : Arginine (also commonly called L-arginine ) breaks down into nitric oxide within the body, which is an important compound for arterial and heart health. Arginine has also been shown to improve circulation , help strengthen the immune system and has a positive influence on male libido.
Related: Threonine: The Amino Acid Needed for Collagen Production
Collagen peptides contain the same exact set of amino acids and nutrients as collagen but have undergone a process called hydrolysis to break them down into shorter chains of proteins.
Not only can hydrolyzed collagen be dissolved in both hot or cold water, but it’s also much easier for your stomach to break down and digest. It also has a high bioavailability and can be absorbed into the bloodstream more readily than regular collagen protein, giving you more bang for your buck when it comes to nutrition.
Best of all, collagen peptides can help improve skin and hair, relieve joint pain, and optimize the health of your gut.
Collagen vs. Gelatin
Curious if collagen is different than gelatin and how it differs from other proteins already found inside in the body? You might have heard collagen and gelatin mentioned in the same breath. That’s because gelatin is derived from collagen — when collagen breaks down, it becomes gelatin.
The process can be found in bone broth : Bones are loaded with collagen, and as the bones simmer in broth during the cooking process that takes place over one to two days, the collagen slowly breaks down into gelatin.
Gelatin was actually one of the first foods used as medical treatment in ancient China.
Gelatin great for people with food allergies or sensitivities. It even helps their bodies manage difficult-to-digest foods better long term by helping repair parts of the gastrointestinal tract.
As a rich source of gelatin, sources of collagen like bone broth can facilitate healing of the mucosal lining, which means improvements in nutrient absorption and less risk for leaky gut (particles leaching out from the gut to where they shouldn’t be). In other words, gelatin is full of the same good stuff as collagen, just in a different form.
Collagen Benefits and Uses
What does collagen do for your body? Below are some of the top benefits associated with this critical protein:
1. Improves Health of Skin and Hair
Why is collagen good for skin? It’s considered the No. 1 collagen benefit for a reason.
Increasing collagen levels can help your skin look firmer , increase smoothness, and help your skin cells keep renewing and repairing normally. According to one randomized, triple-blind, placebo-controlled study, it also helps counteract the effects of aging and collagen loss, such as looser skin, more wrinkles and less elasticity.
Other double-blind, placebo-controlled studies investigating the anti-aging properties of collagen have found that 2.5–5 grams of collagen hydrolysate used among women aged 35–55 once daily for eight weeks can significantly improve skin elasticity, skin moisture, transepidermal water loss (dryness) and skin roughness, all with little to no side effects.
This makes it one of the best natural skin care ingredients available. Collagen benefits also include reducing cellulite and stretch marks.
When skin loses its elasticity as a result of decreased collagen, there’s another side effect: more visible cellulite. Because your skin is now thinner, cellulite becomes more evident — no more hiding what’s happening below the surface.
Collagen for skin helps maintain elasticity and reduce potential dimpling.
2. Reduces Joint Pains and Degeneration
Have you ever felt like you have “skeleton legs,” the types that feel extra stiff and cause pain when you move? That’s likely a loss of collagen rearing its ugly head.
When we lose this vital protein, our connective tissues (including our tendons and ligaments) start moving with less ease, leading to stiffness, swollen joints and more.
With its gel-like, smooth structure that covers and holds our bones together, collagen allows us to glide and move without pain. Think of ingesting more collagen like greasing a creaky door hinge: It helps your joints move more easily, reduces pain often associated with aging and even reduces the risk of joint deterioration.
It’s no surprise then that a 2019 study even found that collagen is an effective treatment for osteoarthritis and other joint pain and disorders.
A double-blind, placebo-controlled, randomized, clinical study on the effectiveness of collagen peptides for osteoarthritis demonstrated that collagen is a “potential therapeutic agent as a nutritional supplements for the management of osteoarthritis and maintenance of joint health.”
Another study published in the International Journal of Medical Sciences found that people with osteoarthritis joint pain treated with type 2 collagen show significant enhancements in daily activities, such as walking up stairs, ascending or sleeping, and a general improvement in their quality of life.
3. Helps Remedy Leaky Gut
If you suffer from leaky gut syndrome, a condition where bad-for-you toxins are able to pass through your digestive tract, collagen can be super-helpful. It helps break down proteins and soothes your gut’s lining , repairing damaged cell walls and infusing the gut with amino acids.
The biggest digestive benefit of consuming more collagen is that it helps form connective tissue and therefore seals and heals the protective lining of the gastrointestinal tract. Today, we know that many illnesses can actually be traced back to inflammation or irritation stemming from an unhealthy gut.
Studies have found that in patients with inflammatory bowel disease, serum concentrations of collagen are decreased. Supplementing with collagen peptides may help treat gastrointestinal symptoms and inflammation, including leaky gut syndrome, IBS, acid reflux, Crohn’s disease and ulcerative colitis.
In addition to helping treat leaky gut, the benefits of collagen include helping with the absorption of water within the intestines, keeping things moving more freely out of body.
4. Boosts Metabolism, Muscle Mass and Energy Output
A boost in collagen may help increase your metabolism by adding lean muscle mass to your frame and helping with the conversion of essential nutrients.
One of glycine’s most important roles is helping form muscle tissue by converting glucose into energy that feeds muscle cells. Remember that retaining muscle mass is crucial as you age, since it helps support posture and bone health and burns more calories than fat.
When consuming collagen, you can benefit from also consuming vitamin C to ensure your body can convert the collagen into a useable protein. This can begin to restore the source or your energy and vitality.
That’s not all that glycine can do for your metabolism. Research shows glycine also has important roles in both functions of the digestive and central nervous systems, which play big roles in maintaining a healthy, youthful body.
Glycine seems to help slow the effects of aging by improving the body’s use of antioxidants and is also used in the process of constructing healthy cells from DNA and RNA.
In addition, it’s been found that arginine
boosts the body’s ability
to make proteins, which is important for repairing muscle tissue, treating wounds, sparing tissue wasting, boosting the metabolism, and aiding in proper growth and development.
5. Strengthens Nails, Hair and Teeth
Ever had peeling and splitting nails? Well, a lack of collagen could be to blame.
Collagen protein is the building block of your fingernails, hair and teeth. Adding it into your diet regimen can help keep your nails strong and possibly reverse signs of hair loss.
A study published in the Journal of Investigative Dermatology found that there’s an “essential relationships between extracellular matrix (ECM) and hair follicle regeneration, suggesting that collagen benefits could include being a potential therapeutic target for hair loss and other skin-related diseases.”
Another double-blind, placebo-controlled study concluded that adult women taking collagen experienced improvements in overall hair volume, scalp coverage and thickness of hair body after 90 days. Additional improvement after 180 days included hair shine, skin moisture retention and skin smoothness.
6. Improves Liver Health
If you’re looking to detox your body of harmful substances, improve blood flow and keep your heart young, collagen is extremely helpful. That’s because glycine helps minimize damage your liver experiences when it absorbs foreign substances, toxins or alcohol that shouldn’t be passing through it.
One of the easiest ways to cleanse your liver is with a bone broth fast . I often recommend a three-day bone broth detox to rapidly help repair leaky gut. This may help your body rid itself of chemicals and “reset” your gut, improving overall immune function.
Studies have even found that glycine can be used to help reduce alcohol-induced liver damage and other forms of acute or chronic liver injury.
7. Protects Cardiovascular Health
The amino acid proline helps your artery walls release fat buildup in the bloodstream, shrinking the fat in the arteries and minimizing fat accumulation. Proline is needed for tissue repair within the joints and arteries — plus it helps control blood pressure.
As part of collagen found within joints, it buffers our bodies from the effects of vibration or shock and helps us hold on to valuable cartilage as we get older. It’s also linked with the prevention of arteriosclerosis (hardening of the arteries) since it helps our arteries stay clear of dangerous plaque buildup.
In addition, arginine helps with nitric oxide production, which allows for better vasodilation — meaning the widening of arteries and relaxation of muscle cells and blood vessels that allows for better circulation.
What Causes Collagen Loss?
Our body’s collagen production naturally begins to slow down as we age. We can thank this degenerative process for signs of aging, such as wrinkles, sagging skin and joint pains due to weaker or decreased cartilage (hello, skeleton legs).
Other lifestyle factors — like eating a diet high in sugar, smoking and high amounts of sun exposure — also contribute to depleting collagen levels.
It’s been found that collagen-related diseases most commonly arise from a combination of either genetic defects, poor intake of collagen-rich foods , nutritional deficiencies and digestive problems affecting production (synthesis) of the protein.
Best Sources (and Types)
Which foods are high in collagen? When it comes to sources of collagen we get from our diets, the main ones are foods very high in protein , including beef, chicken, fish and egg shell membranes.
Here’s a bit about how these differ and benefit us:
- Bovine (cow or beef) collagen: Bovine collagen comes from cows, specifically from their skin, bones and muscles. It’s made of mostly types 1 and 3 collagen, which is a good fit considering these are the most abundant types created and found in the human body. It’s a rich supply of glycine and proline and therefore useful for creatine production, building muscle and also helping the body make its own collagen.
- Chicken collagen: The type most abundant in chicken collagen is type 2, which is best for building cartilage. This makes it beneficial for joint health, especially since this source also provides chondroitin sulfate and glucosamine sulfate — both of which have anti-aging effects. Most supplements containing collagen usually use chicken collagen and provide type 2.
- Fish collagen: Collagen derived from fish has been found to be easily absorbed and provide mostly type 1 collagen, with the amino acids glycine, proline and hydroxyproline. Because type 1 can be found throughout the entire body, consuming more fish collagen has been associated with benefits for the joints, skin, vital organs, blood vessels, digestion and bones. Hydroxyproline is an important component of the collagen triple helix, and lower levels have been associated with joint degradation and therefore symptoms/signs of aging. Hydroxyproline is needed for collagen stability and is created by modifying normal proline amino acids after the collagen chain is built. This reaction also requires vitamin C (to assist in the addition of oxygen), which is why vitamin C deficiency can cause abnormalities in collagen levels.
- Egg shell membrane collagen: Egg collagen , found in the shells and whites of eggs, contains mostly type 1 collagen. It also has type 3, 4 and 10, but by far the most type 1, just like the human body (approximately 100 times more type 1 than type 4). It provides glucosamine sulfate, chondroitin sulfate, hyaluronic acid and various amino acids that have benefits for building connective tissue, wound healing, building muscle mass and reducing pain/stiffness.
A little known fact is that there are at least 16 different types of collagen within the human body. These include types 1, 2, 3, 5 and 10. However, the vast majority — between 80 percent and 90 percent — consists of types 1, 2, and 3.
Type 1 collagen specifically accounts for almost 90 percent of the body’s supply, according to some findings. There are also different types of collagen found in certain foods or used to create collagen products and supplements.
What are the best collagen types? Here’s an overview of the different types of collagen, collagen sources and their primary benefits so you can determine what type is the best:
- Type 1/Type I: This is by far the most abundant and considered to be the strongest type of collagen found in the human body. It’s made up of eosinophilic fibers that form parts of the body, including tendons, ligaments, organs and skin (dermis). Type 1 collagen also helps form bones and can be found within the GI tract. It’s very important for wound healing, giving skin its stretchy and elastic quality, and holding together tissue so it doesn’t tear.
- Type 2/Type II: Type 2 collagen primarily helps build cartilage, which is found in connective tissues. The health of our joints relies on cartilage made of type 2 collagen, which is why it’s beneficial for preventing age-associated joint pain or various arthritis symptoms.
- Type 3/Type III: Type 3 collagen is made of reticular fibers and a major component of the extracellular matrix that makes up our organs and skin. It’s usually found with type 1 and helps give skin its elasticity and firmness. It also forms blood vessels and tissue within the heart. For these reasons, deficiency in type 3 collagen has been linked to a higher risk for ruptured blood vessels and even early death, according to results from certain animal studies.
- Type 4/Type IV: Type 4 collagen has the important job of forming basal lamina, which is found in endothelial cells that form tissue that surround organs, muscles and fat. Basal lamina are needed for various nerve and blood vessel functions. They line the majority of our digestive organs and respiratory surfaces. Basal lamina can be found in the spaces between the top layer of skin/tissue and the deepest layer. They’re a thin layer of gel-like fluid that provides cushion/padding for the tissue above it.
- Type 5/Type V: This type is needed to make the surface of cells, as well as hair strands and tissue found in women’s placentas (the organ that develops in the uterus during pregnancy, provides oxygen and nutrients to the growing baby, and removes waste).
- Type 10/Type X: Type 10 helps with new bone formation and forming articular cartilage. It’s involved in the process of endochondral ossification, which is how bone tissue is created in mammals. It’s been found to be beneficial for bone fracture healing and repairing of synovial joints.
Related: Beef Gelatin: What Are the Benefits & How Does It Compare to Collagen?
Supplements and Dosage
When it comes to choosing a collagen supplement, you want to consider which form is best for you — for example, powder or capsules — and also which types best suit your needs.
While some supplements may contain only one or two types of collagen, other collagen products may offer a blend of several different types.
When looking for an oral collagen supplement, ideally choose a hydrolyzed collagen peptide product, such as a powder, which features the type that’s most absorbable. Look for terms like “collagen peptides,” “collagen hydrolysate” or “hydrolyzed collagen” on the ingredients label of your supplement to ensure you get the real deal.
How to Use:
Is it good to take collagen every day? For most people, yes.
The top ways to consume more include:
- Making or drinking real bone broth.
- Using protein powder made from bone broth in recipes. You can consume bone broth on its own or use it in all sorts of sweet and savory recipes depending on the type of product.
- Taking collagen supplements. A collagen supplement can be found typically as hydrolyzed collagen, which helps form new collagen — this may take the form of collagen protein powder or collagen pills. When you hydrolyze collagen, collagen peptides become bioavailable.
- Eating a well-rounded diet that helps increase absorption of the collagen peptide you consume.
How to Prevent Collagen Loss
Our ancestors chowed down on quite a bit of collagen as a natural way of life, since earlier traditional diets incorporated whole-animal eating. Simply put, they ate many animal parts, like skin, tendons and ligaments, that we now commonly avoid or discard.
Luckily, it’s becoming easier than ever to “get back to the basics.” One of my favorite ways to increase collagen consumption is by making a homemade bone broth, like my chicken bone broth recipe , or the find some made from beef. It’s a healthy, delicious and cost-effective way to use parts of an animal that can’t be eaten directly — no waste here!
Bone broth is also insanely good for you. As these inedible animal parts simmer for hours or days, they release collagen in an easy-to-absorb broth.
Collagen supplements, like collagen protein powder, are another easy way to increase your collagen intake. Make sure that you get your powder from grass-fed, pasture-raised cows (with no antibiotics or chemicals).
Collagen supplements can be mixed into smoothies, soups or even into baked goods to provide healthy benefits without adding any taste to your favorite meals.
For your skin, you can also try microneedling , or collagen induction therapy. It’s a minimally invasive skin treatment in which a dermatologist or aesthetician intentionally creates tiny punctures in the top layer of skin using micro-fine needles.
Fortunately, any negative collagen side effects are rare. Most people who experience negative side effects from collagen either went over recommended dosages or have pre-existing allergies.
Check the sources of collagen on the supplement bottle. If you’re allergic to fish and fish collagen is used in the product, then obviously avoid.
If the supplement only lists the collagen types, then it’s important to know that type 2 collagen is usually chicken, while types 1 and 3 can be bovine, fish or egg whites. If you are allergic is any of those proteins, then steer clear.
It’s not really a collagen powder side effect, but one complaint some users register may be a bad aftertaste from the powder or pills. This bad taste will go away in a few minutes, but it can usually be avoided altogether by taking the powder in a smoothie, for example.
- Collagen, a type of structural protein that helps to form and repair connective tissues throughout the body, is responsible for health benefits including support for joints, skin, hair, nails and digestion.
- There are many factors that support the formation and use of it in the body — such as vitamin C, manganese, copper, proline and foods high in anthocyanidins (such as blueberries, cherries and blackberries).
- Make sure to opt for collagen peptides to optimize the bioavailability and digestion of your supplement.
- Lastly, be aware that certain foods promote collagen growth more than others. Animal products, like eggs, poultry, fish and milk, can all help boost collagen formation. But veggie lovers, fear not! You can also use collagen in recipes for your family or kids, such as homemade healthy jello or all-natural fruit snacks.