🦴Collagen
The most abundant protein in the human body — collagen peptide supplements provide the specific amino acids hydroxyproline and glycine that stimulate the body's own collagen synthesis, with clinical evidence for improving skin elasticity, reducing joint pain, supporting gut barrier integrity and contributing to bone density.
What It Is
Collagen is the most abundant protein in the human body — comprising approximately 30% of total protein and forming the structural scaffolding of skin, joints, bones, blood vessels and the gut lining. Collagen production declines approximately 1% per year after age 20, with this decline accelerating dramatically after 40, contributing to skin aging, joint deterioration and gut permeability.
Hydrolyzed collagen peptides are collagen that has been enzymatically broken into small peptide fragments (primarily dipeptides and tripeptides) that are absorbed intact into the bloodstream. Clinical research has shown these peptides — particularly hydroxyproline-containing dipeptides — accumulate in skin and cartilage tissue where they stimulate fibroblasts and chondrocytes to produce more of the body's own collagen, creating a self-amplifying collagen synthesis effect.
Nutritional Highlights
Health Benefits
- Randomised trials confirm collagen peptides significantly improve skin elasticity and hydration after 8-12 weeks
- Reduces the appearance of wrinkles by stimulating fibroblast collagen and elastin production
- Hydroxyproline dipeptides accumulate in skin where they directly signal collagen synthesis
Why it works: Collagen peptides — particularly prolyl-hydroxyproline dipeptides — are absorbed intact from the gut and transported to skin tissue where they activate fibroblast receptors, triggering increased production of type I collagen and elastin. Multiple randomised controlled trials confirm significant improvements in skin elasticity, hydration and wrinkle depth with 8-12 weeks of daily supplementation.
- Clinical trials in athletes and osteoarthritis patients confirm reduced joint pain with collagen supplementation
- Hydroxyproline peptides accumulate in cartilage and stimulate chondrocyte collagen production
- Associated with reduced need for pain medications in osteoarthritis patients in research
Why it works: Collagen peptides accumulate selectively in cartilage tissue where they stimulate chondrocytes (cartilage cells) to produce more type II collagen — the primary structural protein of articular cartilage. Clinical trials in both athletes with joint pain and osteoarthritis patients confirm significant pain reduction and improved joint function.
- Glycine and glutamine in collagen support intestinal epithelial cell function
- Collagen provides the structural proteins of the gut lining that maintain barrier integrity
- Associated with reduced gut permeability in early clinical research
Why it works: The gut lining is a collagen-rich structure whose integrity depends on adequate glycine and proline availability for collagen synthesis. Collagen peptide supplementation provides these amino acids in highly concentrated form, supporting the structural maintenance of the gut barrier that prevents "leaky gut" — the excessive intestinal permeability associated with inflammatory conditions.
- Bone is approximately 30% collagen by weight — providing the flexible organic matrix into which minerals are deposited
- Collagen peptide supplementation combined with calcium and Vitamin D improves bone mineral density in postmenopausal women in clinical research
- Reduces bone resorption markers while increasing bone formation markers
Why it works: Bone mineral density depends on both the mineral content (calcium, phosphorus) AND the organic collagen matrix into which minerals are deposited. Collagen peptides support the organic matrix component of bone — the aspect most neglected by conventional calcium supplementation alone. Clinical research finds collagen supplementation combined with minerals produces superior bone density improvements than minerals alone.
- Glycine in collagen supports creatine synthesis in the liver and kidneys
- Combined with resistance exercise, collagen supplementation increases lean mass more than protein alone in elderly men in clinical research
- Reduces exercise-induced muscle damage markers
Why it works: Collagen provides glycine — the amino acid required (alongside arginine and methionine) for creatine biosynthesis in the body. Adequate glycine intake supports endogenous creatine production that fuels high-intensity exercise. Clinical research finds collagen combined with resistance exercise more effective for lean mass gains in older adults than resistance exercise alone.
- Provides the amino acid building blocks for keratin synthesis — the structural protein of hair and nails
- Associated with reduced nail brittleness and breakage in clinical research
- Supports scalp collagen that anchors hair follicles
Why it works: Hair and nails are primarily composed of keratin, whose synthesis requires proline, glycine and hydroxyproline — the amino acids most concentrated in collagen peptides. Collagen supplementation provides these substrates in quantities that support improved keratin production, explaining the hair thickness and nail strength improvements documented in clinical research.
How to Use It
Recommended Products
Safety & Considerations
- Generally safe at recommended doses of 10-15g daily for most people
- Marine collagen is derived from fish — those with fish allergy must avoid marine collagen and choose bovine or chicken instead
- Collagen is an animal product — not suitable for vegans
- Quality varies significantly — choose brands with third-party testing
- High glycine content may cause mild digestive discomfort in some individuals at high doses
This content is for informational purposes only and is not intended as medical advice. Always consult a qualified healthcare professional before making changes to your diet, supplement use, or treatment plan.
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