Common proteins are partially digested into free amino acids, but collagen peptides are not completely digested into free amino acids. Instead, they are partially digested and absorbed as oligopeptides, such as Proline-Hydroxyproline (Pro-Hyp) or Glycine-Proline-Hydroxyproline (Gly-Pro-Hyp). It has been demonstrated that 30-40% of Hyp is absorbed in these peptides.
When collagen peptide is digested, the free amino acids can be utilized as raw materials for protein synthesis. On the other hand, Hyp peptides circulate in the blood and stimulate cells in the skin, joints, and bones. This stimulation affects cell activation/suppression and/or growth, leading to collagen synthesis or other cellular responses. This indicates that collagen plays a unique role in the body, beyond simply serving as a protein.
Nippi has demonstrated that oral intake of Nippi Fish Collagen Peptide offers various beneficial effects.