Collagen is an interesting case of an ingredient that has been almost completely tranformed in the past 15 years or so because of accumulating scientific research. At the beginning of this journey the whole protein molecule was not particularly highly thought of, because of its poor showing on the PDCAAS (protein digestibility-corrected amino acid score) scale, a scale which matches all proteins against egg protein, which gets a perfect score of 1.0, as a standard for amino acid profile completeness.

However, the health supporting properties of collagen have led to both a burgeoning amount of research and booming sales. Here we dig into the latest published science on collagen since 2021.

Collagen scores a 0 on the PDCAAS scale because of a complete lack of tryptophan, one of the essential amino acids. This led the molecule, which is otherwise easy to formulate with, to be used as a relatively low value add-in to things like nutrition bars to plump up the protein content.

However, the health-supporting properties of collagen have led to both a burgeoning amount of research and booming sales. According to Nutrition Business Journal, collagen notched $252 million in sales in 2022 and saw 14.6% year over year growth.

A total of 24 studies published since the start of 2022 are captured using "collagen supplementation" as the search term.

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Traditional beauty

As far as its properties beyond raw protein contrubition are concerned, collagen has been most frequently studied for its benefits for healthy nails and skin and that continues to be the case.

One recent randomized, double-blind, placebo-controlled study conducted in South Korea added to the scientific backing for those effects by studying the effect of "low molecular weight collagen peptides" on skin wrinkles and other markers of epidermal health. The researchers scored the effects by comparing before and after photos of skin wrinkles (a common approach) and conclude that crow's feet wrinkles were reduced and the skin of the collagen was better hydrated.

Sports wins and losses

Some of this researhc has focused on sports nutrition endpoints, and the findings there have been mixed. A recent study in the International Journal of Sports Nutrition and Exercise Metabolism found that, for a small cohort of young men, whey protein did a better job of supporting muscle protein synthesis than did "leucine-matched collagen peptides."

The lead of the research grou[p, Prof. Stuart Phillips of McMaster University, has done a number of studies along this line. Phillips attributed collagen's relative lesser performance to its lower leucine level compared to whey. He also mentioned the absence of tryptophan.

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"With those features it becomes hard to reconcile how collagen could support muscle protein synthesis. Perhaps supporting other tissues could be a proposition for collagen peptides," Phillips said in an interview published in 2020.

Another study, published in the journal Acta Physilogica, found that collagen peptides performed getter than placebo in helping young male subjects build muscle and increase flexibility after a course of resistance training.

Bone end points

Another study conducted by a group in Greece focused on collagen peptides and their effects on bone health markers in older women. Vitamin D and calcium are a common one-two punch for bone health supplementation.

The Greek study, which is remarkable in that it ran for a full year, aimed to see if the poositive effects of those two mainstays could be improved with the addition of collagen peptides. The study compared collagen peptides in a relatively high dose (5 grams a day) in conjunction with vitamin D and calcium to the effects of calcium and vitamin D alone.

The researchers found that the addition of collagen significantly improved bone mineral density and bone structure in the population of postmenopausal women with osteopenia. This is a gradual bone demineralization which can be a precursor to outright osteoporosis.

As with sports nutrition studies, hoever, studies on collagen in connection with bone health also present mixed results. A brand new study published in the journal Bone found that a daily dose of a commercially available collagen drink that supplied 18 grams of collagen did not result in greater bone formation after a jump test meant to induce bone stress. The study was small and very short term, however, at only three days.

Peptides

But at the leading edge of collagen research are ingredient developers who have drilled down into specific collagen peptides.

To get a comprehensive look at new research and applications from collagen peptide ingredient suppliers – including resistance training, muscle tissue, joint health, digestion and more – click here to download the free Natural Products Insider digital magazine, "Collagenation."