Collagen: What Is It and Why All the Hype?

Dr. Patrick Carroll, MD
Medically reviewed by Patrick Carroll, MD Written by Our Editorial Team Last updated 11/15/2019

Within the past year or two, the popularity of and curiosity surrounding collagen has skyrocketed. You want to know what’s behind the hype, but type it into Google and you’re hit with well over 100 million results — almost too overwhelming to be helpful. 

Like many popular nutrition topics, it’s difficult to weed fact from fiction when it comes to collagen, particularly with so many sources competing for your attention. But understanding the basics of this building block of your body is a good place to start. 

Here, we’ll break down the very basics of collagen: what it is, what it does in your body, things you can do to make (or get) more of it and how to begin supplementing with it. 

TL;DR What You Should Know 

  • Collagen is abundantly found within the human body. 
  • It is a compound largely found in connective tissues — including skin, ligaments and tendons — and is said to be as strong as steel. 
  • As we age, our ability to produce collagen decreases, leading to wrinkles and lost elasticity in the skin. 
  • Certain foods like bone broth and JELL-O® contain collagen, which is derived from animal sources. 
  • Smoking and sun exposure can damage or decrease existing collagen.
  • There are many collagen supplements on the market.

What Is Collagen? 

Collagen is one of the most prevalent proteins in the human body. In fact, it makes up about one-third of your body’s total protein, and if all of the moisture was removed from your skin it’d make up about 75 percent of your flesh, by weight (Lovely thought, right?). It’s found throughout your connective tissues, including your bones and cartilage, but it's also found in your eyes and blood vessels.

There are 28 different types of collagen, each named with a Roman numeral. The feature that unites these 28 different substances is the triple-helix structure of their molecules. Depending on which type of collagen you’re looking at, this structure can make up as much as 96 percent of it (in collagen Type I) or as little as 10 percent (in collagen Type XII). While this fact may seem a little more than you need to know, it’s this structure that makes collagen unique and is notable enough that researchers call it “elegant.” You so fancy, collagen. 

Collagen is not unique to humans. It’s the most common protein among all animals, which is why the overwhelming majority of collagen supplements you see are animal-derived. In fact, many — if not most — of collagens labeled as vegan or vegetarian don’t actually contain collagen. They usually contain plant-based ingredients and are often advertised as collagen builders because they ostensibly promote the body’s natural production of collagen (if you are into that idea, note that similar claims are made of vitamin C). 

The Role of Collagen in the Body 

Knowing what collagen is doesn’t necessarily explain what it does in the body. Collagen is a compound in connective tissue that is very strong — Type I, the most abundant, is stronger than steel, according to researchers. Essentially, it plays a huge role in holding your body together. As a matter of fact, collagen has been used to make glue for ages — as far back as Ancient Egypt. So it’s pretty good at holding things together. 

Your bones, ligaments, tendons, cartilage and even teeth are largely made up of collagen. It plays a major role in your skin’s health — its elasticity in particular — and the results of it degrading as we age is seen in wrinkles and saggy skin.

The various types of collagen serve different purposes within the body. Type I, for example, is the most abundant form within your body and is mostly found in the skin, bones, tendons and ligaments. Type II, on the other hand, is more common in cartilage and parts of the eye. And Type III is prevalent in the skin, intestines and blood vessels. 

When it comes to collagen in the skin, what we have isn’t guaranteed tomorrow. As a matter of fact, it’s estimated that adults produce one percent less collagen in their skin each year from age 20 on. This slowed production compounds and ultimately leads to thin, more fragile skin as we age. 

Nutritional Choices for Collagen Production

There are two main lines of thinking here: some foods contain collagen and others may help your body increase its own production of the protein. 

Vitamin C stands out as one widely researched promoter of collagen synthesis. For starters, vitamin C is required by the skin to produce collagen. So there’s that. And as one may expect, a vast array of skin care products (eg, vitamin C serums) boast vitamin C as a key ingredient. 

However, the jury is still out on vitamin C in a clinical setting. Adding foods with high vitamin C content to your diet (read: fruits and vegetables) has been shown to positively correlate with skin health in a number of studies, animal studies have shown that vitamin C supports collagen synthesis and a limited number of human studies suggest that vitamin C supplementation could have a positive effect on recovery time after musculoskeletal injuries.  

Also, while there is speculation that chlorophyll (found in plants like aloe vera) and astaxanthin (found in some seafood) can improve the skin’s production of collagen, more research is needed for it to gain scientific acceptance.  

Foods That Contain Collagen 

Foods that naturally contain collagen are largely animal products — those of us who are vegan or vegetarian may want to skip to the next section now. As with humans, collagen is an important protein across the animal world, so it stands to reason they’re a rich source of dietary collagen as well. 

Foods high in naturally-occurring collagen include things made of animal connective tissue (like bone broth or cartilage), some seafood and gelatin — yes, as in JELL-O. Believe it or not, the gelatin in your favorite childhood dessert is made from animal connective tissues.

If you’re not into the types of food that contain collagen, you can mix a collagen supplement into your food. Currently, there are numerous collagen supplements on the market. These are generally labeled as hydrolyzed collagen or collagen peptides — both referring to the fact that the collagen has been broken down to make it more easily dissolvable. 

Lifestyle Factors That May Affect Collagen Levels 

While it’s an inevitable truth that your collagen levels will decrease as you get older, there are also things you can do to damage the collagen you have. Two lifestyle choices in particular have been found to degrade collagen in your body: smoking and getting too much sun. 

Smoking damages collagen synthesis in the skin, leading to poor wound healing and increased skin aging. This is one of the many — many, many, many — reasons you’re advised to stop smoking before having an operation (and in general).  

Additionally, research shows that UV radiation causes photo-aging in skin and damage to the collagen and elastin fibers in it.

Smoking and unprotected sun exposure are bad for your health for a multitude of reasons. If you needed another reason to avoid both, here it is. 

Ways to Supplement with Collagen 

The choices are many. There are collagen peptides (aka hydrolyzed collagen) as well as snacks and smoothies with collagen already in them. While there are pill options out there, hydrolyzed collagen supplements most often come in powder form. They may be flavored or unflavored. Because the collagen has been broken down into peptides or amino acids, it dissolves easily into liquids.  

Collagen Supplements Side Effects

Just like anything you ingest, it’s good to know what potential negative consequences collagen supplements could potentially have on your body.

Check the label to ensure there are no allergens you need to worry about. If you’re allergic to any of the typical sources of collagen — like bovine, fish or poultry — you should be especially careful before adding collagen supplements to your diet and make sure the particular supplement you choose isn’t derived from something that makes you break out into a rash (or worse). 

Aside from that, most adverse effects of collagen are experienced somewhere in the digestive tract. 

If you’re unsure about starting a supplement regimen and the potential health effects it could have for you, talk to your doctor about your plans. And of course, you should always tell your healthcare provider what supplements you are taking — especially if you also take prescription medication — since some supplements interact with drugs. 





This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.