How It Works

Provides specific amino acids (glycine, proline, hydroxyproline) that are rate-limiting for collagen synthesis. Stimulates fibroblasts to produce new collagen. May work via glycine's anti-inflammatory and sleep-promoting effects.

Dosage & Timing

Dosage Guide

Daily Dose10-20 g

TimingAnytime. Often taken with vitamin C (cofactor for collagen synthesis). 30-60 min before bed may improve sleep via glycine.

BioavailabilityHydrolyzed collagen (peptides): ~90% absorption. Undenatured type II collagen works differently — immune-modulating for joints at much lower doses (40mg).

Optimal Timing

Take with food. Consistency matters more than timing for most supplements.

Cycling & Duration

No cycling required — safe for continuous daily use.

Best Forms (Ranked)

Bovine Collagen (Types I+III) — ★★★★★

Best for skin, hair, nails. Most researched. Our top pick.

Marine Collagen (Type I) — ★★★★☆

From fish. Better absorption claimed. More expensive.

Undenatured Type II — ★★★★☆

For joint health specifically. Much lower dose (40mg). Different mechanism.

Evidence-Based Benefits

Skin elasticity and hydration improvement (8-12 weeks)
Joint pain reduction (moderate evidence)
Nail strength and growth
Gut lining support (glycine)
Sleep quality (via glycine content)

Side Effects & Safety

Digestive discomfort at high doses
Fishy aftertaste (marine collagen)
Not a complete protein — don't count toward daily protein target

✅ Good For

Skin aging prevention
Joint pain (especially athletes)
Gut health support
Those eating mostly muscle meat (low glycine intake)
Nail/hair strength

⚠️ Skip If

Vegetarians/vegans
Those getting enough glycine from bone broth/whole-animal eating
Kidney disease (high protein load)

Stacks Well With

Vitamin C Hyaluronic Acid Glycine Magnesium

💊 Collagen Peptides