Collagen – large and small molecules

Collagen can be divided into: large molecule collagen and small molecule collagen peptides.
The gums in the food we normally eat contain large molecules of protein with a molecular weight of 300,000 daltons or more, which are not directly absorbed after consumption, but are broken down into amino acids in the digestive system, waiting to be reorganized, and it is unknown whether they eventually make up collagen, which has a very low absorption rate.

People have controlled collagen with molecular weight up to 6000 daltons by acid-base and enzymatic cleavage techniques and called it collagen peptide. A peptide is a substance between amino acids and macromolecular proteins. Two or more amino acids are dehydrated and condensed to form several peptide bonds to form a peptide, and multiple peptides are folded at multiple levels to form a protein molecule. Peptides are precise protein fragments with nanometer-sized molecules, which are easily absorbed by the stomach, intestines, blood vessels and skin, and their absorption rate is much higher than that of large molecule proteins.

Collagen peptides with a molecular weight of 6000 daltons or less are subdivided into peptides with a molecular weight of 1000-6000 daltons and peptides with a molecular weight of 1000 daltons or less. Generally, the number of amino acids in oligopeptide is from two to nine. According to the number of amino acids in the peptide, there are different names: the compound formed by dehydration condensation of two amino acid molecules is called dipeptide, and by the same analogy, there are tripeptide, tetrapeptide, pentapeptide, etc., until nine peptides; usually the compound formed by dehydration condensation of 10-50 amino acid molecules is called polypeptide.
In 1960s, it has been proved that oligopeptide can be absorbed without gastrointestinal, which can greatly reduce the burden of gastrointestinal and liver and improve the bioavailability; and it can directly participate in the synthesis of human collagen without breaking down into amino acids, while peptide cannot achieve these.
Therefore, you should pay attention to the molecular weight of collagen peptides when you buy them.