Ingredient guide
What is collagen?
An introduction to collagen, the body's main structural protein, and how Collagen Science compiles the research.
Collagen is the most abundant structural protein in the human body, forming a major component of skin, tendons, ligaments, bone, and other connective tissues. Supplemental collagen is usually sold as hydrolyzed collagen (also called collagen peptides) derived from animal sources. Collagen Science is an independent project that compiles peer-reviewed research on collagen and summarizes what each study set out to measure and what it reported, linking to the original sources. This page is informational only and is not a substitute for advice from a healthcare professional.
Explore the collagen guide by question
The structured guide connects this foundational page to the product comparison and focused research summaries.
Open the full collagen guide →
Collagen Types Explained
How collagen types are marketed and what product forms usually mean in practice.
Open guide →Collagen for Skin
Research context for collagen peptides, skin hydration, elasticity, and appearance claims.
Open guide →Collagen for Joints
Evidence context for collagen and joint-pain outcomes.
Open guide →Collagen for Hair and Nails
How hair and nail claims fit into the collagen evidence base.
Open guide →Collagen and Bone Density
Bone-density research context and why outcomes differ from skin and joint claims.
Open guide →Marine vs Bovine Collagen
A product-selection comparison between common collagen sources.
Open guide →Product comparison
An evidence-informed comparison of leading hydrolyzed collagen peptide powders, evaluated on form, labeled dose, sourcing, transparency, and testing.