If you are a regular reader you know that I am always interested in the newest things, but skeptical about products and procedures making claims that aren’t proven with hard evidence from clinical trials. Collagen supplements are becoming increasingly popular, but because they are not required to undergo FDA trials, I have long had doubts about whether they could actually make a difference for aging skin. But some companies have tested their collagen products with double-blind prospective studies, so I decided to review them to see where the trail of bread crumbs led. What I found surprised and impressed me.
There is good reason to think that collagen supplements would be bogus. Collagen is the main structural protein in the skin and connective tissues of the body, and like all proteins it is comprised of chains of molecules called
amino acids. There are different types of collagen, such as elastin which provides elasticity, but with all of them the chains wind together to form long interweaving strands. The job of the digestive system is to break proteins down into the individual amino acids, so they can be reassembled into things that the body needs at the time; it shouldn’t matter whether it came from steak, spinach, or a collagen pill. But as it turns out
there are short sequences of amino acids called peptides that escape total digestion. These are actually absorbed and transported to the skin, where certain ones signal collagen production. Here is a summary of studies supporting the use of collagen supplements:
- A dietary supplement improves facial photoaging and skin sebum, hydration and tonicity modulating serum fibronectin, neutrophil elastase 2, hyaluronic acid and carbonylated proteins. Di Cerbo et al, 2015. This 2 part study first identified blood serum markers associated with visual signs of skin aging, correlated to decrease in skin hydration, elasticity and increased skin pH and sebum compared to “healthy” controls. A specific supplement improved all of these features after 4 weeks of use.
- An Insight into the Changes in Skin Texture and Properties following Dietary Intervention with a Nutricosmeceutical Containing a Blend of Collagen Bioactive Peptides and Antioxidants. Genovese et al, 2017. This double blind, prospective study demonstrated a significant increase in skin elasticity and an improvement in skin texture after daily oral consumption of the nutricosmeceutical for 90 days.
- Dietary Supplementation with Specific Collagen Peptides Has a Body Mass Index-Dependent Beneficial Effect on Cellulite Morphology. Schunck et al, 2015. This double-blind, placebo-controlled clinical study investigated the efficacy of specific bioactive collagen peptides (BCP) on cellulite. The degree of cellulite including skin waviness and dermal density was evaluated before starting the treatment and after 3 and 6 months of intake. BCP treatment led to a statistically significant decrease in the degree of cellulite and reduced skin waviness on thighs in normal weight women. The efficacy of BCP treatment was also confirmed in overweight women, although the impact was less pronounced in comparison with women of normal body weight.
- Ingestion of bioactive collagen hydrolysates enhance facial skin moisture and elasticity and reduce facial ageing signs in a randomised double-blind placebo-controlled clinical study. Inoue et al, 2016. This randomized double-blind placebo-controlled clinical trial compared ingestion of two types of collagen hydrolysates (partially broken down collagen), which are composed of different amounts of bioactive peptides, on improvement of skin conditions such as moisture, elasticity, wrinkles, and roughness. Compared with a placebo group at baseline, and 4 and 8 weeks after the start of the trial, this study demonstrated that the use of the collagen hydrolysate with a higher content of peptides Pro-Hyp and Hyp-Gly led to more improvement.
- Oral Ingestion of Collagen Hydrolysate Leads to the Transportation of Highly Concentrated Gly-Pro-Hyp and Its Hydrolyzed Form of Pro-Hyp into the Bloodstream and Skin. Yazaki et al, 2017. This study analyzed the plasma concentration of collagen-derived peptides after ingestion of high tripeptide-containing collagen hydrolysate in humans. They identified 17 types of collagen-derived peptides transiently, with a particular enrichment in Gly-Pro-Hyp, proving that these peptides survive digestion and can be delivered to the skin and other organs.
- Oral supplementation of specific collagen peptides has beneficial effects on human skin physiology: a double-blind, placebo-controlled study. Proksch et al, 2014. This double-blind, placebo-controlled trial randomized 69 women aged 35-55 years were to receive 2.5 g or 5.0 g of collagen hydrolysate (CH) composed of specific collagen peptides or placebo once daily for 8 weeks. At the end of the study, skin elasticity in both CH dosage groups showed a statistically significant improvement in comparison to placebo. After 4 weeks of follow-up treatment, a statistically significantly higher skin elasticity level was determined in elderly women.
Despite these well-done studies, a few caveats remain. For one, scientifically measurable changes in skin do not always translate to visual improvement. While these studies clearly go beyond the claim that every skin cream makes that you will see “improvement in the appearance of fine lines,” individual results will vary. And it is probably important to make sure that the supplement you decide on has the actual collagen peptides that have been studied. Most likely they are not actually serving as building blocks for collagen production, but as signaling molecules.
So with collagen supplements, the truth may be more than skin deep!