Matrixyl

How it works

KTTKS, a procollagen fragment, on a fatty tail to enter skin. Sold to cue fibroblasts, the collagen-making cells, to make more.

What it's made of

5 amino acids (KTTKS) from type I procollagen, the piece that is trimmed off when collagen is made, with a tail of palmitic acid (a fat) so it gets into the skin. Sold by Sederma (France).

What it's for

Prescribed for

Nothing: it is a cosmetic.

Sold as

“Stimulates your own collagen”: it fills wrinkles from the inside.