Collagen supplements and collagen-rich bone broth are hot health trends in the U.S. in recent years. And some people have been sold on the benefits of collagen for much longer. Women in China have eaten collagen-rich donkey hide to improve their complexions for thousands of years. Chinese women still line up to eat donkey hide at Wang Pang Zi Donkey Burgers in Beijing, hoping the collagen-rich hide (which resembles thick, wet leather) will keep their skin healthy and beautiful. An assortment of drinkable collagen supplements also fly off the shelves in China and Japan.
But is collagen the healthy skin, joint, and bone elixir many people believe it to be? Or is it an overhyped fad? Keep reading to find out what the scientific research says, get a primer on different types of collagen supplements, and learn the potential benefits and drawbacks of trying them.
Collagen is the most abundant protein in the body. It makes up one-third of the body’s protein, and is found in bones, skin, muscles, tendons, and fascia. It holds the body together and provides strength and structure. Collagen helps keep your skin smooth and firm, your joints flexible and pain-free, and your bones healthy.
There are three types of collagen in the body. Type I is in the skin, hair, nails, organs, bone, and ligaments. Type II is in the joint cartilage, and Type III is in cartilage, bone, dentin, and tendons.
Your body makes collagen (called endogenous collagen) out of the amino acids in food. But it’s normal for collagen formation to decrease as you age. High sugar consumption, smoking, excessive exposure to sunlight, and autoimmune disorders may hasten the loss.
Decreasing collagen levels contribute to common effects of aging, such as wrinkles, sagging skin, joint pain, and bone loss. But experts differ on whether they think taking collagen supplements (called exogenous collagen, meaning it comes from outside the body) can counteract these normal effects of aging.
Types of Supplemental Collagen
Most collagen supplements are made from the bones and tissues of fish, chickens, pigs, or cows. There are three different types of supplements: collagen protein, gelatin, and collagen peptides.
This is collagen in its whole form. It consists of three long chains of more than 1,000 amino acids. They’re tightly twisted into a helix, making them strong enough to serve as the scaffolding of an animal’s body. Collagen protein is hard to digest and the least effective way to take supplemental collagen. (But be sure to read the entire label on a supplement to find out how it was made. Sometimes manufacturers use “collagen protein” as a generic term for any type of collagen.)
This substance is formed when collagen protein is broken down into shorter chains of amino acids using a process called hydrolysis. To understand hydrolysis, think about making bone broth, where you reduce the collagen in animal bones and tissues into gelatin by boiling them for a long time. In gelatin, water partially breaks collagen down to make a gel. It’s more bio-available than collagen protein, meaning it’s easier for the body to digest and use.
These substances are formed when collagen is broken down completely using hydrolysis into much shorter chains of amino acids. (Sometimes collagen peptides are called hydrolyzed peptides or collagen hydrolysate.) Collagen peptides are the easiest type of collagen for the body to digest and use, and thus they may be the most beneficial to take.
What the Science Says About Supplemental Collagen
The body doesn’t absorb any type of exogenous collagen whole. The digestive process breaks it into separate amino acids. Some evidence suggests the body uses the amino acids derived from collagen supplements to produce more of its own endogenous collagen.
The evidence is strongest when it comes to joint health. In one study, 60 patients with Rheumatoid Arthritis took type II chicken collagen for three months. They experienced a significant decrease in joint swelling and tenderness with no side effects, and four participants experienced remission from the disease. Meanwhile, the group who took placebos saw no benefits. In another study, it reduced joint pain in osteoarthritis patients by 40 percent within 90 days of treatment.
At least one study suggests collagen may also improve bone health. In a randomized, placebo-controlled study of 131 postmenopausal women, specific collagen peptides improved bone density in the femoral neck and lumbar spine with no side effects.
The evidence that collagen supplements improve skin health is less robust. The studies conducted so far are small and some are industry-funded. But their preliminary findings suggest collagen may improve skin elasticity and hydration and speed wound healing. When elderly women in one study took collagen for four weeks, they had a statistically higher skin elasticity level. And in a double-blind, placebo-controlled study of 100 women, participants who took a specific bioactive collagen peptide for eight weeks had a 20 percent reduction in wrinkle depth around their eyes.
Potential Safety Risks
Study participants haven’t experienced side effects, but that doesn’t mean collagen supplements are completely safe. Studies tend to follow participants for only a few months and don’t track longer-term risks.
Because most collagen supplements are made from animal bones and tissues, some doctors are concerned they may contain contaminants and heavy metals. Many supplement companies claim they do rigorous testing for heavy metals, but supplements aren’t regulated by the Food and Drug Administration.
Supplemental collagen seems to be helpful for joint pain and possibly bone health. The research on its beauty benefits is thin, but preliminary studies suggest it may help improve skin elasticity, decrease the appearance of wrinkles, and speed up wound healing. Taking collagen doesn’t seem to cause short-term side effects for most people, although longer-term side effects are unknown.
Are you interested in taking supplemental collagen? As noted above, some people eat collagen-rich donkey hide. But supplements probably sound more appetizing. Look for a reputable brand with a third-party certification label, such as CL, NSF, or USP. These seals verify that supplements contain what they say and aren’t contaminated with dangerous substances, such as arsenic or bacteria. Ideally, also choose a company that sources their bones and tissues from free-range, cage-free, antibiotic-free animals.