Collagen supplements were once dismissed as digested-before-absorbed. New research tells a different story.

What Is Collagen?

Collagen is the most abundant protein in the body, forming the structural framework of skin, joints, bones, and tendons. We produce less as we age — 1% less per year after age 25.

Why Hydrolyzed Peptides Matter

Unlike whole collagen (which is digested to amino acids), hydrolyzed collagen peptides (2–5 kDa) are absorbed partially intact and signal fibroblasts to produce new collagen.

The 2023 Meta-Analysis

A pooled analysis of 19 RCTs covering 1,125 participants found:

• Skin hydration: +12.4% after 90 days
• Elasticity: +14.2%
• Wrinkle depth: -16.8%

Dosing: What Works

Clinically effective doses are 2.5–10g daily for at least 8–12 weeks. Results below 8 weeks are often not measurable.

Collagen Types

Type I and III (bovine or marine) are best for skin. Type II (chicken) is joint-specific. Marine collagen has the smallest peptide size and highest bioavailability.