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Hydrolysed Collagen Protein Oral Supplement

Collagen Peptides

Hydrolysed Collagen · Collagen Hydrolysate · Types I, II, III

"The most widely consumed peptide supplement on earth — and one of the most underrated in this book. Not because the science is overwhelming, but because it works where it matters: skin, joints, tendons, and gut. The entry-level peptide with a genuine evidence base."

Type
Hydrolysed collagen · 2–10 kDa peptides
Key types
Type I (skin/tendon) · Type II (cartilage) · Type III
Status
UK: food supplement · widely sold over-the-counter · WADA: not specifically listed · US FDA: GRAS (Generally Recognised As Safe) — highest food-ingredient safety classification
Route
Oral powder or capsule
Protocol summary
Standard dose
10–20 g/day oral
Tendon protocol
15 g + 50 mg vit C, 60 min pre-exercise
Duration
8–12+ weeks for visible skin effect
Evidence-based
10–20 g/day oral · with vitamin C · 8–12 weeks minimum for measurable outcomes
Mechanical loading (exercise) is required to direct new collagen synthesis to where it's needed
Origin & Background

The oldest peptide supplement — finally taken seriously

Collagen is the most abundant protein in the human body — accounting for approximately 30% of total protein mass. It is the primary structural component of skin, tendons, ligaments, cartilage, bone, and blood vessels. Collagen peptides are produced by hydrolysing (enzymatically breaking down) whole collagen from animal sources (bovine, porcine, marine, or chicken) into smaller peptide fragments of 2–10 kDa — small enough to be absorbed intact through the intestinal wall.

Gelatine has been consumed for centuries, and collagen supplements have been sold for decades. But rigorous clinical trials only emerged substantially in the 2010s. The systematic review by Khatri et al. (2021, Amino Acids) — 15 studies — established that collagen supplementation with vitamin C and mechanical loading significantly improves joint pain, tendon healing, and body composition in athletes. Subsequent RCTs confirmed skin elasticity improvements, wrinkle depth reduction, and nail/hair benefits.

The FDA classifies hydrolysed collagen as GRAS (Generally Recognised As Safe) — the highest safety classification for a food ingredient. This is the only peptide in this book with that status. No prescription, no cycling, no monitoring required. It is simply a food.

How it works differently from most peptides: Collagen peptides don't bind receptors or signal through hormonal pathways. They provide direct substrate (glycine, proline, hydroxyproline) that fibroblasts use to build collagen, and some fragments (like prolyl-hydroxyproline and hydroxyprolyl-glycine) act as signalling molecules stimulating fibroblasts to increase collagen production. They work through nutrition and local signalling, not systemic pharmacology.

Science & Mechanism

Substrate provision plus signalling

How Collagen Peptides Work

1
Hydrolysis and absorption: Enzymatic hydrolysis breaks whole collagen into peptide fragments of 2–10 kDa. These are absorbed intact through the intestinal wall — including the dipeptides prolyl-hydroxyproline (PO) and hydroxyprolyl-glycine (OG) which have been detected in blood after oral supplementation.
2
Substrate provision: Collagen is rich in glycine, proline, and hydroxyproline — amino acids that are rare in most dietary proteins but essential for collagen synthesis. Supplementation provides these specific precursors directly to fibroblasts, chondrocytes, and osteoblasts.
3
Fibroblast signalling: PO and OG dipeptides stimulate fibroblast collagen production — acting as signalling molecules, not just substrate. This is why collagen peptides appear more effective than equivalent amino acid mixtures (like gelatine + glycine) in some studies.
4
Vitamin C dependency: Collagen cross-linking (the step that makes fibres strong rather than just assembled) requires vitamin C as an essential co-factor for prolyl hydroxylase and lysyl hydroxylase enzymes. Without adequate vitamin C, collagen synthesis stalls at the cross-linking stage — explaining why vitamin C is always co-administered in high-quality collagen protocols.
5
Mechanical loading requirement: Collagen fibres are laid down along lines of mechanical stress. Without appropriate loading (exercise, tendon loading), newly synthesised collagen is disorganised and weaker. This is why the timing of collagen supplementation relative to exercise matters.

The Shaw et al. (2017) study established the key protocol: 15g hydrolysed collagen + 50mg vitamin C, taken 60 minutes before exercise, significantly increased collagen synthesis markers in tendons compared to placebo. This timing (1 hour pre-exercise) is now the standard recommendation for tendon/ligament applications. The Khatri systematic review (2021, 15 RCTs) confirmed benefits for joint pain, recovery, and body composition across the evidence base.

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Benefits & Evidence

What the data shows

🦴
Joint pain and osteoarthritis
Multiple RCTs and systematic reviews show significant reduction in joint pain, particularly in knee OA. Most consistent effects at 10g+/day for 12+ weeks. Khatri (2021) systematic review: significant improvement in joint pain across 15 studies. Type II collagen (undenatured) has additional oral tolerance mechanism.
● Strong — multiple RCTs and systematic review
🏋️
Tendon and ligament healing
Shaw (2017): 15g collagen + 50mg vitamin C, 60 min pre-exercise, significantly increased collagen synthesis markers in tendons vs placebo. Clark (2008): significant reduction in activity-related joint pain in athletes. Best evidence in sports medicine for any OTC supplement.
● Strong — RCT data with mechanistic support
✨
Skin elasticity and hydration
Multiple RCTs showing improved skin elasticity, hydration, and wrinkle reduction at 2.5–10g/day for 8–12 weeks. Proksch (2014): 2.5g/day for 8 weeks significantly improved skin elasticity in women 35–55. Consistent across multiple manufacturers and formulations.
● Strong — multiple RCTs
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Body composition (lean mass)
Zdzieblik (2015): 15g collagen peptides daily + resistance training increased fat-free mass and muscle strength more than placebo + training in elderly men. Mechanism: collagen provides glycine for creatine synthesis and glutamine for muscle recovery.
● Moderate — single well-designed RCT
🧠
Gut integrity (glycine)
Collagen is rich in glycine — the most abundant amino acid in the gut lining. Glycine has anti-inflammatory and protective effects on intestinal epithelium. Collagen supplements are used in gut healing protocols, though evidence is more mechanistic than RCT-based.
● Limited — mechanistic · limited direct RCT evidence
Things to know

Risks & considerations

🛡️
The safest supplement in this book by a significant margin. FDA GRAS status. No known drug interactions. No hormonal effects. No cycling required. No monitoring needed. The only meaningful risks are allergic reactions in people with fish/shellfish allergies (marine collagen) or bovine allergies (bovine collagen).
Mild
GI discomfort — mild bloating or digestive upset in some people, usually dose-dependent. Splitting doses or taking with food resolves this.
Mild
Allergic reactions — fish/shellfish allergy: avoid marine collagen. Bovine allergy: avoid bovine collagen. Chicken allergy: avoid Type II chicken collagen. Always check source.
Mild
Hypercalcaemia risk (rare) — some collagen supplements are combined with calcium. High-dose calcium supplementation carries cardiovascular risks. Check supplement composition.
🔒
Members only
Full protocol guidance — doses, timing, administration routes, stacking and member reports — available with a Pep IQ subscription.
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