While the evidence on collagen is far from conclusive, most clinicians agree there's little downside in trying it if you wish -- as long as you keep expectations in check and a few things in mind.
Collagen is the most abundant protein in the body. It provides structure and support to tissues, including skin, hair and nails, as well as muscle, bone, cartilage and tendons.
"It's like the frame within your mattress," said Dr. Joshua Zeichner, the director of cosmetic and clinical research in the Department of Dermatology at Mount Sinai Hospital in New York. "Within skin, the frame is the collagen, the springs are the elastic fibers, and the stuffing is the hyaluronic acid."
Our body continuously makes new collagen, but the process begins to slow down after about age 30. This is what contributes to wrinkling and a crepey appearance of skin, according to Zeichner.
Other factors, such as stress, sunlight, pollution, smoking and a diet high in sugar, can also accelerate collagen loss. On the other hand, eating a protein-rich diet, along with proper sunscreen use and a good skincare routine, can preserve collagen.
What's inside a collagen supplement
Beef, pork and marine life are all popular sources for collagen supplements, which offer the protein in a hydrolyzed form. That means it's broken down into smaller units, including amino acids and peptides, that are easily absorbed and can find their way into tissues, including the skin.
The supplements specifically contain high amounts of three amino acids that are key building blocks for collagen synthesis in the body: glycine, proline and hydroxyproline.
The supplements usually come in a protein powder form, or as a pill -- although collagen protein bars and gummies also exist. The powders can be flavored or unflavored, and can be added to any warm liquid, like coffee; tea; oatmeal; soups; sauces; and even baked goods.
Bone broth liquids and powders derived from beef or chicken can also be a good source of collagen, though there isn't much evidence of skin or joint benefits, according to Dr. Patricia Farris, a dermatologist and fellow of the American Academy of Dermatology.
How ingestible collagen works
Taking a collagen supplement, Zeichner said, "is similar to what your body would experience after a steak dinner, except without the fat."
The way they work is twofold: One is that the supplement's amino acids may protect the body's existing collagen by functioning as antioxidants, where they block the action of enzymes that break down collagen and ultimately prevent the development of wrinkles, Farris explained.
The other is that you simply produce more collagen by feeding your body peptides, the short chains of amino acids your cells use as collagen building blocks. In fact, according to Zeichner, high levels of collagen peptides may actually trick the body into thinking its natural collagen is breaking down, stimulating the formation of new collagen as a result.
There isn't much definitive data on ingestible collagen, but preliminary research suggests that supplements may help build lean muscle mass; improve skin hydration and elasticity; reduce skin wrinkling; and reduce joint pain and/or stiffness -- although it may take at least three months to experience benefits, according to ConsumerLab.com.
Should you use it?
According to experts, there's simply not enough data and standardization to make good clinical recommendations on ingestible collagen.
"I won't tell you not to do it if you want to take it, but I don't have a product that I can steer people to that's been fully tested," Farris said.
The studies that have been performed "have been small and mostly company-funded, and it can take about eight weeks of daily use to see a benefit," added Dr. Tod Cooperman, president and founder of ConsumerLab.com.
Research results also haven't given a clear picture of how collagen may visibly impact a person's skin. One study
measured a 17.7% reduction in eye wrinkle volume after 8 weeks of ingesting a hydrolyzed collagen, but it remains unclear whether that reduction is significant enough to produce visibly appreciable changes, Farris explained.
Then there's the fact that demographic groups may be limited in studies -- for example, a study may find improvements in skin elasticity
among a group of women with fair complexions, but that doesn't tell you anything about those in other demographic groups, such as older, male or darker-skinned individuals, said Dr. Anne Chapas, a dermatologist and the medical director at Union Square Laser Dermatology in New York.
Additionally, it's often hard to tease out if it's the collagen that's responsible for any benefits, or if it's something else in the formula, people's diets or their skincare routines.
"I think the hard thing about my patient population is that they're not doing this in isolation -- they're using antioxidants, retinoids, laser treatments and fillers, and sunscreen," said Dr. Karyn Grossman, a clinical professor of dermatology at the University of Southern California and owner of Grossman Dermatology in Los Angeles and New York City.
Another factor to consider is that mild side effects may occur. These can include gastrointestinal symptoms, headache, dizziness or rash, according to ConsumerLab.com.
Overall, a collagen supplement may be best suited as an add-on to a healthy diet that is rich in nutrients but might have minor gaps in consistency, said Jen Scheinman, a Colorado-based registered dietitian nutritionist who takes collagen and recommends it to about half of the women in her private practice.
"I use collagen a few days per week ... and my skin definitely looks firmer and healthier. It has a more youthful look and feel, and my hair and nails seem stronger too," Scheinman said. "[Results] are not an overnight thing, but from a good three months of regularly taking it. Part of why I like it is because it's a good, easy source of protein. If people are struggling to get protein in, it can dissolve tastelessly in most warm beverages and up people's protein intake while also offering benefits to skin health."
Grossman agrees. "If you are eating very minimal calories, and you're not eating a lot of protein, you may experience a greater benefit by taking a collagen supplement than someone who regularly eats salmon, lean chicken, turkey, broccoli, red peppers, and tomatoes -- all foods that help support collagen synthesis," she said.
But if your diet is a junk food diet, "the collagen addition by itself will not have the same benefit as someone whose diet is healthy and well-balanced," Scheinman added.
How to choose a collagen supplement
"If you are generally healthy, and your kidneys are functioning well, there's no harmful health effect that I know of," said Zeichner. "I am not usually proactively recommending (collagen supplements), but for patients who ask I'm certainly supportive of it, along with a healthy diet and a good skincare routine."
Yet as with other dietary supplements, manufacturers of collagen supplements do not have to prove that their products are safe and effective
before they line store shelves. Because of this, it's important to consult with a board-certified dermatologist on whether the ingredients are right for you, Chapas advised.
Here are some other things to consider when choosing a collagen supplement:
- Go for quality. Scheinman recommends that bovine collagen peptides be sourced from organic, grass-fed cows, while marine collagen supplements should be non-GMO and wild caught. "Ultimately what this means is a cleaner collagen supplement with less contamination," Scheinman said.
- Know your allergies. Those with sensitivities to fish, for example, should steer clear of marine-sourced collagen.
- Research the manufacturer. Check to make sure the company has been tested for heavy metals or other contaminants. You can review ConsumerLab's newly released test results on collagen supplements, including approved and not-approved sources, here. Zeichner also advised choosing a supplement from a company that has some published data showing effectiveness.