This article was written by Jonny Bowden, Ph.D., C.N.S., and originally published in Amazing Wellness magazine.

Everyone from beauty junkies to biohackers are dumping packets of collagen into their coffee, blending it into smoothies, and even cooking with it. But what’s this important protein really all about? Glad you asked…

What Is Collagen?

First, a few basic facts about collagen. The most abundant protein in our body, collagen is found in our skin, nails, hair, joints, muscles, bones, and more. It gives our connective tissues their structure, and works with the protein elastin to keep them firm.

While our bodies can produce collagen on their own, that ability to do so declines as we age. We don’t know why collagen production declines with age, but it does—and dramatically. After age 20, we produce one percent less collagen in our skin per year. By the time we hit our 40s, we essentially stop making it altogether.

The result: wrinkles, thinning skin, brittle hair and nails, and joint, bone, and muscle issues (like stiffness and aching). Since the protein isn’t part of the average modern American diet, supplements made of the protein have taken off.

Collagen vs. Gelatin

If we’re going to talk about collagen supplements, we first need to sort out the gelatin-collagen relationship.

Raw collagen comes from animals—particularly parts of the animal that we usually don’t eat, like gristle, cartilage, tendons, and bones. When we cook those animal parts—as we do when we simmer bones in a broth for extended periods of time to make bone broth—that collagen heats up and turns into gelatin. Yep, that gelatinous, waxy yellow substance floating around in your bone broth? That’s it.

The Bone Broth Situation

Issue is, bone broth isn’t a particularly efficient way to get collagen into your body. At least not if you want that collagen to do what it’s known for (like improving joints and skin).

Gelatin, the form of collagen found in bone broth, is made up of strings of amino acids called peptides. These big molecules need to be broken down further for you to make the most of them. Though your body will absorb collagen protein in this form, it won’t effectively break it down into small enough particles for it to be of maximum use.

That’s where hydrolyzation comes in. Hydrolyzation breaks collagen down into tiny, microscopic particles that the body can just suck up and put right to use where it need it. It’s this form of collagen that’s used in collagen supplements designed to support skin, hair, nails, and joints.

Bone broth is a terrific food that supplies a rich array of vitamins, micronutrients, and some collagen in the form of gelatin—but if you want collagen for more specific purposes, hydrolyzed collagen supplements are the way to go.

Collagen I, II, and III

Though there are many varieties of collagen supplements out there, most fall into one of two categories: products that provide collagen types I and III, and products that provide collagen type II.

There are actually at least 16 different types of collagen found throughout the body, but types I, II, and III make up about 90 percent of our total collagen. Collagen I and III, which are almost always found together, are mainly found in our skin. Collagen II, meanwhile, is found in our joints.

Related: I Drank Collagen Every Day For A Month—Here’s How It Went

Thus, collagen supplements intended for skin-related benefits typically combine collagens I and III. Those intended for joint support, though, contain type II.

Collagen Protein Powders

While collagen supplements have long been a great way to support skin and bones, the recent collagen protein powder trend has one major advantage: A high-quality collagen protein powder offers a much greater dose of collagen than your average capsule.

Clinical studies suggest that 10 grams per day of pharmaceutical-grade collagen improves chronic joint issues. A second, 24-week study found that athletes who took a collagen hydrolysate supplement also experienced improvement joint discomfort. What’s more, one recent review concluded that collagen hydrolysate is of interest as a way to address joint and bone related issues associated with aging.

Fish or Beef?

If you’ve done your homework on collagen, you know supplements typically source the protein from one of two animals: beef or fish. (Nope, there’s no such thing as vegan collagen.)

Though fish collagen hasn’t been around as long as beef collagen, it does boast a few definite selling points. Most notably, fish collagen peptides are smaller than beef collagen peptides, and studies have shown that they are very well absorbed and digested. Since they are so easy on the gut, many naturopathic doctors recommend fish collagen supplements for patients with any gut issues or sensitivity. Plus, fish collagen is also high in a particularly valuable amino acid—hydroxyproline—which seems to play a particular role in stimulating collagen synthesis. A recent study showed that people who supplemented with antioxidants and fish collagen experienced improved measures of skin elasticity and moisture.

If you go for beef collagen, though, make sure the product you choose comes from healthy, sustainably-raised cows.

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