Collagen supplements, shakes, and shots are everywhere, promising improved skin hydration, elasticity, and wrinkle reduction. But, is there any substantial evidence behind the claim that ingested collagen is “scientifically proven” to deliver visible results? Celebrity spokespeople and dozens of testimonials don’t equal evidence-based medicine.
What is collagen?
Collagen is the most abundant protein in the body, making up about a quarter of our weight. It’s large and considered the key structural component of bone, blood vessels, cartilage, tendon, and skin. It’s so important that it’s conserved across all animals, meaning pigs to chickens to fish to humans all have a lot of it. Diseases where collagen production fails are devastating. Think Samual Jackson’s character in the movie Unbreakable. Born with Osteogenesis Imperfecta, a rare condition where collagen synthesis is flawed, he suffered extremely fragile bones and recurrent fractures. Or think Scurvy, a disease where collagen synthesis stalls because of a lack of vitamin C. Vitamin C is an essential cofactor necessary for collagen production, and without it, transatlantic sailors lost teeth, vision, cartilage and bone.
But what doesn’t work for patients with these two diseases is eating collagen. Why? Because collagen is a large, complex protein that goes through an elaborate synthesis process. Water and sugar molecules are added to and subtracted from collagen precursor molecules as it’s assembled into its final form in body tissues. When we consume collagen in the form of food, its long-chain proteins are digested and broken down into smaller building blocks called amino acids. These are absorbed, make their way into the blood stream, and are delivered to parts of the body where they become available for new collagen synthesis. From a dietary perspective, you’re body doesn’t care and can’t tell if you ate a collagen pill, chicken, quinoa, or chick peas. They are all sources of protein, are broken down similarly, and reach your blood stream as the same amino acid building blocks. For this reason, the concept that eating collagen diminishes skin wrinkles is too simplistic. More is involved than consuming large amounts of protein.
Collagen is a critical component of the skin. It gives our skin its structure and shape. When we’re young, we have an abundance of well-organized collagen. But, as we age, the cells that make collagen begin to slow their production, and environmental stressors like UV radiation and cigarette smoke break down its structure further. Collagen fibers thin and become less organized, leading to wrinkles and facial lines. The good news is that we have tools to stimulate collagen synthesis. Resurfacing lasers like the fractionated CO2 laser can boost collagen production by creating microscopic wounds in the skin. This initiates a healing response that leads to new collagen production as a way to “fix” the injured skin. Soft tissue fillers like Restylane and Juvederm injected under the skin have also been shown to stretch the cells that produce collagen, stimulating them to synthesize more. But, back to collagen supplements. Even if the amino acid breakdown products of ingested collagen make it to the skin, and some of them definitely do, we don’t yet know if their presence alone is enough to jump start collagen production. Excess input doesn’t always translate into excess production.
But, what about the studies?
Of the studies that attempt to link ingested collagen to improved skin hydration, elasticity, and fewer wrinkles, they have problems. Many have been conducted in test tubes or in mice, where results don’t necessarily translate to humans. Of those studies performed in people, most are quite small involving a couple dozen participants; so again, it’s hard to know if results are more generalizable. Statistical significance is another practical barrier. For those studies with “positive” results, many document small “statistically significant” improvements in skin parameters, but fail to show before and after photographic improvement1-3. Although a slight statistical change may be interesting, if you and I can’t actually see a visible difference, statistics don’t matter. Finally, most of the studies to date have been funded by the manufacturers of the supplements, which of course may introduce bias…
It is possible that collagen supplements, shots and shakes provide meaningful clinical benefit to more youthful skin, but to date, there is no overwhelmingly sound evidence suggesting that’s the case. Knowing what collagen is, how it’s absorbed, and how it’s actually synthesized in the body, it seems unlikely that eating an extra 5000mg will have meaningful clinical benefit. For now, it may be just as economic to splurge on your favorite protein filet, enjoy it, but don’t expect it or any collagen supplement to be a facial fountain of youth.
- A study to assess the effect on wrinkles of a nutritional supplement containing high dosage of hydrolysed collagen” in Cosmeceuticals, Issue 3. June 2014.
- Effects of a nutritional supplement containing collagen peptides on skin elasticity, hydration and wrinkles” in Journal of Medical Nutrition and Nutraceuticals, December 2014.
- Daily consumption of the collagen supplement PURE Gold Collagen® reduces visible signs of aging” accepted by Clinical Interventions in Aging, October 2014.
