Collagen supplements are one of the buzziest wellness ingredients on the market today. With touted hair, skin, nail, and gut benefits, chances are you’ve seen your favorite influencer singing the praises of collagen on social media. But like many other nutrition fads, there has been quite a bit of controversy around the truthfulness of the health benefits of collagen supplementation.

From promoting skin health to strengthening nails to providing gut support, it seems as though everyone has something to say about collagen. With insight from two registered dietitians (three including myself!), we set the record straight on the different types of collagen, how they impact the body, what research tells us about the efficacy of supplementation, as well as myths about collagen.

What is collagen?

Simply put, collagen is a type of protein found abundantly throughout the body. This is thanks to the fact that it’s the main component of connective tissue. In fact, 30 to 40 percent of the body’s total protein is collagen.

“There are two key amino acids needed for collagen production: proline and glycine. Vitamin C then converts proline into hydroxyproline, another essential amino acid component of collagen,” explains Kristen Carli, RD, owner of Camelback Nutrition & Wellness and co-founder of Expert with Influence. 

Inside our cells, these three amino acids (proline, glycine, and hydroxyproline) come together to form procollagen, which becomes collagen. And while the body produces collagen on its own, eating foods rich in these amino acids, like legumes, eggs, dairy, fish, meat, and poultry, can greatly support this natural process. Foods naturally rich in collagen, including meat, fish, and poultry, can also promote collagen formation.

What is collagen good for?

Because collagen is critical in forming connective tissues, it plays many roles throughout the body. As the name implies, connective tissue attaches tissues of the body to each other. Thus, collagen is prevalently found in skin, bone, muscle, tendon, and cartilage tissues, offering both structure and elasticity. 

Many also swear by collagen supplementation for gut health. Some small¹ human and animal studies have supported this notion while others have not found² collagen to offer gastrointestinal benefits. Ultimately, there isn’t enough conclusive peer-reviewed evidence to support this claim quite yet.

The 5 different types of collagen

Interestingly, there are 28 different types of collagen⁶³, characterized by amino acid structure and where they’re utilized in the body. “However, five types are more commonly recognized,” says Lena Bakovic, RDN, registered dietitian at Top Nutrition Coaching.

Type I

“Type I collagen⁴ is the most abundant throughout the body and is found in skin, bones, tendons, and ligaments, providing structure and strength,” Carli says.

Type II

Type II collagen⁵ is vital for joint health and function as it is primarily located in cartilage, helping to cushion joints, provide stability, and promote flexibility.

Type III

Type III is found in muscles, skin, cartilage, and bone marrow. “However, type III collagen is also present in reticular fibers, which support the structure of organs, like the liver, spleen, and blood vessels,” Carli adds.

Type IV

Type IV⁷ collagen is most abundantly found in the skin. Carli explains that type IV collagen is also readily found in epithelial cells, which are the most pervasive cells throughout the body and cover the skin, blood vessels, and body cavities.

Type V

And finally, type V collagen⁸ supports the formation of bones, cell surfaces, muscles, organs, and the placenta in pregnant folks.

What happens to collagen as you age?

“With the aging process, collagen production decreases,” Bakovic says. In fact, somewhere between our 20s and 30s (depending on the person), the body’s ability to naturally replenish collagen decreases by anywhere from one to 1.5 percent, according to a 2021 review⁹ in Plastic and Aesthetic Research. 

This is partly why our skin, joint, muscle, and bone health can start to wane as we get older. Common signs of lower collagen production include fine lines and wrinkles, dry skin, dull or brittle hair and nails, stiff muscles, and achy joints.

Habits that can decrease collagen

Aside from the natural aging process, lifestyle factors can also decrease collagen levels and production throughout the body. These include smoking, excessive refined sugar consumption, and ultraviolet (UV) light exposure. 

As if we needed another reason to avoid cigarette smoking, evidence shows us that this taboo practice is tied to decreased collagen production¹⁰—not to mention elastin (the protein that gives skin and other organs elasticity) damage. Meanwhile, added refined sugars have been linked to collagen fiber cross-linking¹¹ and advanced glycation end products (AGEs) production¹², both of which damage collagen. And finally, UV light can degrade local collagen stores¹³.

How to increase your collagen levels

While opting for foods rich in collagen and amino acids, like glycine and proline, is always the best place to start, collagen supplements may also be helpful in building up your stores. “Studies¹⁴ have shown that collagen supplements can help improve skin elasticity, hydration, and reduce wrinkles, making the skin look younger and healthier. They can also reduce pain and improve mobility, especially in people with osteoarthritis¹⁵, and may support muscle mass and prevent bone loss¹⁶,” Carli explains.

Foods that increase collagen

When looking for foods that can help to naturally increase collagen levels, there are so many options. Foods rich in the foundational amino acids of collagen include eggs, dairy, legumes, nuts, seeds, meat, fish, and poultry. Alternatively, you can choose foods naturally rich in collagen, like fish, poultry, and meat.

There are also some micronutrients that support collagen production, including vitamin C¹⁷, copper¹⁸, and zinc¹⁹. Vitamin C is in tomatoes, bell peppers, citrus, berries, broccoli, melon, and kale (to name just a few). Nuts, seeds, mushrooms, whole grains, shellfish, and leafy greens are excellent sources of copper. And oats, nuts, seeds, legumes, seafood, and meat are rich in zinc.

Best types of collagen powders

“There are many varieties of collagen supplements on the market, which may be helpful in combating declining collagen. And while many of these products have differing sources, they all offer many of the same benefits, ” Bakovic says.

So, whether you’re having lobster for dinner, adding a bovine-based collagen to your morning smoothie, or sipping on some bone broth, all of these practices are going to help you reap the benefits of collagen. Though they may offer different types of collagen.

In the world of collagen supplements, there are three main options: marine, bovine, and hydrolyzed. Here’s more info about them.

1. Marine Collagen

As the name implies, marine collagen is derived from seafood sources and often contains types I, II, or III collagen, though it is especially high in type I²⁰. This is a major benefit as type I collagen tends to be more bioavailable²¹—perfect for supplementation. “Though, some individuals may be allergic to the fish or shellfish source and should take extra care to read the label of these products,” Carli says.

2. Bovine Collagen

Collagen derived from the bones, hides, and cartilage of cows is more commonly known as bovine collagen. This variety tends to be rich in type I and III collagen²², however evidence points to this type of collagen being less bioavailable than marine options²³.

3. Hydrolyzed Collagen

When optimal absorption is your top priority, hydrolyzed collagen may be your best bet. This is because the proteins in hydrolyzed collagen supplements have been partially broken down into smaller molecules, helping the body to better absorb them²⁴. You may see hydrolyzed collagen advertised as “super collagen” or “collagen peptides,” and these options will usually be either bovine or marine-based. But because of this extra processing, these products may be a bit pricier than other collagen supplements.

FAQs

What type of collagen is the best?

Due to its increased bioavailability, marine collagen (bonus points if it’s hydrolyzed) can be one of the most effective varieties. Plus, many people feel a little less off-put by the marine collagen sourcing process. 

One of the most popular marine supplements, that just so happens to be hydrolyzed, is California Gold Nutrition Hydrolyzed Marine Collagen Peptides. Given that this product is both marine-derived and hydrolyzed, it’s highly absorbable and easily added to smoothies or water. The fish used to create this product are wild-caught and it is a single-ingredient product which is a very rare find.

In terms of bovine options, Vital Proteins has been a top brand in the collagen space for several years—and for good reason. With hundreds of thousands of positive reviews, customers are beyond satisfied with how well this grass-fed, kosher product works. Plus, it has only three recognizable ingredients and no added sweeteners, additives, dairy, or gluten.

What should I look for when buying collagen?

One of the most important things to look for when shopping for collagen supplements is ethical sourcing. Opting for products that are made from wild-caught fish or organic, grass-fed, and pasture-raised animals is a great way to ensure this. You also want to make sure that there aren’t excessive amounts of additives, fillers, sweeteners, or any other sort of mystery ingredient, as many of these can be pro-inflammatory—or at the very least unnecessary.

As for what types of collagen to look for, “using a supplement that includes multiple types of collagen can provide a more comprehensive range of benefits for the body and are safe to take together,” Carli says. While this specific information won’t necessarily be readily available on supplement packaging, you can determine this from the collagen source.

Do collagen supplements really work?

“There are many varieties of collagen supplements present on the market, which may be helpful in combating declining collagen, though further research is warranted to continue to understand true efficacy,” Bakovic says. However, the studies Carli references above do show that there is peer-reviewed evidence illustrating the efficacy of these supplements for skin, muscle, joint, and bone health.

At the very least, collagen supplements are rich in protein and amino acids that will help your body to build up its own collagen stores naturally.

So, what happens if you take collagen every day?

“Most studies and experts actually suggest taking collagen supplements daily for the best results. This is a safe practice and typical dosage ranges from 2.5 to 15 grams per day, depending on the specific product and the health benefit you are aiming for,” Carli says. However, it’s important to follow the instructions on the collagen powder label and consult with your healthcare professional prior to starting any new supplement, collagen included.

What happens when you stop taking collagen?

This will vary from person to person, but you can expect any positive effects experienced as a result of initiating a collagen supplement to potentially fade away. This could mean increased joint aches, fine lines, or brittle hair—if those were present prior to starting the collagen supplement. But this also may not happen, it’s truly individualized, and there’s no serious harm in stopping a collagen supplement after taking it for any period of time.

Are there any downsides to taking collagen?

Most collagen supplements are safe for most people. “However, some individuals may be allergic to the source of the collagen,” Carli says. Because of this, it’s vital to check the label of whatever product you’re after. 

“People with certain medical conditions, such as advanced kidney disease without dialysis, may not be able to safely tolerate the extra protein content provided from collagen supplements,” Bakovic adds. If you think you might fit within this category, it’s crucial that you speak with your healthcare provider prior to starting a collagen supplement.

It’s also important to note that dietary supplements are not tested for purity, safety, or effectiveness by the Food and Drug Administration (FDA). This places the responsibility on supplement producers to follow honest practices and consumers to do their research. To ensure you’re buying a safe supplement, look for a brand that has been verified by a third party like the National Science Foundation (NSF) and U.S. Pharmacopeia (USP). 

Is there a vegan version of collagen?

Unfortunately, there aren’t any vegan collagen supplements on the market today. “True collagen is derived from animal sources, so there are no vegan collagen products in the traditional sense,” Carli explains. “However, there are vegan-friendly supplements and products marketed as ‘collagen boosters’ or ‘collagen builders,’ that typically contain plant-based ingredients to support the body’s own collagen production rather than providing collagen directly.”