Skin, bones, tendons, cartilage – collagen is the most abundant structural protein in your body. Marine collagen is attracting particular interest at the moment, and the gut is one of the tissues it is discussed in connection with. Find out what the intestinal mucosa is made of and what role collagen plays as a component of connective tissue in the digestive tract.
The collagen context
Before looking at marine collagen and the gut, it is worth understanding what collagen is. It is the main building block of the supporting framework between cells in connective tissues such as skin, bones, ligaments, tendons and cartilage (source). Collagen is the most abundant protein in the human body and a component of skin, bones, tendons, ligaments and cartilage. The intestinal mucosa contains collagen as part of its connective tissue, alongside the epithelial cell layer that lines it.
Marine collagen contains the amino acids proline, glycine and hydroxyproline, which also occur in the collagen structure of the intestinal wall. Collagen peptides supply these amino acids as a dietary component.
Fish collagen: an overview
When it comes to sourcing collagen, options range from beef to pork to fish. Marine collagen comes from sources such as fish skin and bones. Researchers see it as an alternative to beef and pork because it is not subject to religious dietary rules and no transmission of animal diseases has been reported (source).
Sustainability of marine collagen
Marine collagen is obtained from fish by-products such as skin and bones that would otherwise be disposed of as waste. This resource-efficient use promotes sustainable sourcing and actively contributes to environmental protection without negatively impacting wild fish populations. The use of by-products eliminates unethical farming practices, making fish collagen an environmentally friendly alternative.
How small marine collagen peptides are
Marine collagen peptides are very small molecules (low molecular weight). Studies of marine peptides have mainly measured how quickly they appear in the blood after intake.
Origin from the deep sea - quality and purity
High quality fish collagen is sourced from deep sea fish. Like all collagen, it is rich in glycine, proline and hydroxyproline. This natural origin meets high quality standards.
Marine collagen and the gut
The gut plays a central role in overall wellbeing, and maintaining its health is crucial for efficient digestion, absorption of nutrients and a robust immune system. Whether collagen peptides affect digestive symptoms has barely been studied. In one small study without a comparison group, healthy women took 20 g of collagen peptides from cattle daily for 8 weeks, and their digestive symptoms were recorded (source). Without a comparison group, it cannot say whether any changes were due to the collagen, and it tested bovine, not marine, collagen.
What the intestinal mucosa is made of
The intestinal mucosa contains collagen as part of its connective tissue, and glycine is one of the most common amino acids there. Collagen peptides are broken down in the digestive tract and supply those same amino acids.
How collagen peptides are digested
Collagen peptides are broken down in the digestive tract into amino acids and short peptides and absorbed like other dietary proteins. Their amino acid profile is particularly rich in glycine, proline and hydroxyproline.
The body's own collagen and age
With increasing age, the body's own collagen production decreases. Marine collagen supplies the amino acids the body assembles its own collagen from. Studies of collagen peptides have recorded skin elasticity as one of their measures, over periods of several weeks.
Digestion in the stomach
Collagen peptides are a dietary protein and are digested in the stomach like other proteins. Fish collagen can be included in a balanced diet as a neutral-tasting protein source.
Combine marine collagen supplements with gut-healthy foods
The purest form of collagen is generally tasteless and can therefore be consumed in a variety of ways. Here are some foods that combine well with a collagen product.
High-fiber foods
Dietary fibre is an important part of a balanced diet. Your daily diet should include fiber-rich foods such as whole grains, beans, lentils, nuts, seeds, fruits and vegetables. These foods belong in a varied diet.
Fermented foods
Fermented foods contain live microorganisms. Yoghurt, miso soup and kimchi are among these fermented foods. Probiotic foods are easy to fit into a varied diet.
Foods rich in plant compounds
A varied, plant-forward diet is regarded as the foundation of gut-friendly eating. Examples include turmeric, green tea, green leafy vegetables and fruit such as blueberries. These foods combine well with a collagen product.
Conclusion
Marine collagen is highly soluble and supplies the amino acids from which the body's own collagen is built. Research so far has mainly examined how collagen peptides are digested and absorbed.
Sources
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7230273/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6153947/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9198822/
https://www.sciencedirect.com/science/article/pii/S1756464620305028
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9198822
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8718035/