INGREDIENT GLOSSARY

Glycolic acid is the smallest of the alpha hydroxy acids. How does it act on the stratum corneum, what percentages are permitted in cosmetics, how is it used in the evening, and which skin types should avoid it?

Aescin, extracted from horse chestnut seeds, acts on capillary permeability by reducing the passage of fluid into the tissues. What do studies say, what can a cosmetic do, and where does its field of action end?

No antioxidant works alone: some act in the aqueous phase, others in the oil phase, and several regenerate one another. How they really work and how to read an INCI list.

Mallow mucilages do not merely retain water: they slowly release it into the stratum corneum over the course of several hours. Why the skin stops feeling tight, how it differs from marshmallow, and who it is truly suitable for.

Papain directly breaks down the proteins that hold dead skin cells in place, and stops when it runs out of substrate. How it differs from acids, why leaving it on longer doesn’t help, and who should be cautious.

Glycogen is the cells’ energy reserve, and it decreases with age. How it affects the skin, why the plant-based version derived from corn changed the game, and which LeLang product contains it.

Persistent redness, visible capillaries, skin that burns with everything. Acetyl Tetrapeptide-40 targets the inflammatory mechanism behind them: what studies say and when it makes sense to use it.