Absorption of bioactive peptides following collagen hydrolysate intake: a randomized, double-blind crossover study in healthy individuals

Virgilio N, Schön C, Mödinger Y, van der Steen B, Vleminckx S, van Holthoon FL, Kleinnijenhuis AJ, Silva CIF, Prawitt J · Frontiers in Nutrition

Source and molecular weight mattered less than the marketing for either implies. Free hydroxyproline uptake was comparable across all hydrolysates regardless of animal origin or molecular weight, and total hydroxyproline exceeded free hydroxyproline in every case — the signature of substantial di- and tripeptide absorption. The authors state plainly that nobody yet knows what circulating concentration is needed to trigger anything in a target tissue.

Population

Healthy volunteers, randomized double-blind crossover

Intervention

Single doses of collagen hydrolysate from fish, porcine and bovine skin and hide, bovine at 2,000 and 5,000 Da

Limitations

Single-dose pharmacokinetics with no physiological endpoint. All authors are employed by Rousselot, BioTeSys or Triskelion — the manufacturer and its contract laboratories. Group size is not given in the abstract.