L-Lysine
An essential amino acid the body cannot make, used in the cross-links that give collagen its strength.
Substrate reasoning; no human skin trial of supplemental free lysine.
On the label: L-Lysine.
What it does for you
Supports the step that makes collagen strong rather than merely present.
Why we use it
Cross-linking is what turns collagen strands into structure. Lysine and copper are both required for it, which is why they appear together here.
Mechanism
Lysine residues are modified and then cross-linked by lysyl oxidase, a copper-dependent enzyme. Those cross-links are what give collagen its tensile strength.