Retinoid
Retinaldehyde
INCI: Retinal·Studied at 0.05–0.1%·Strong evidence
The retinoid one conversion step closer to retinoic acid than retinol, so it works at a lower percentage. It is studied for the appearance of fine lines and an even tone, and like retinol it oxidises fast in air and light.
Studied for
- ·The appearance of fine lines and wrinkles
- ·The look of a smoother, more refined surface
- ·The appearance of an even tone
How it’s thought to work
Skin converts it to retinoic acid in a single step, one fewer than retinol, and it is studied for association with the appearance of renewed skin; it oxidises readily, so packaging matters.
Layering note
Often kept apart from: direct L-ascorbic acid (vitamin C) in the same layer.
Questions
- Is retinal stronger than retinol?
- It is one conversion step closer to the active form, so it tends to work at lower percentages and can act a little faster. That also means it can feel more assertive at first, so most people ease into it.