The brightest ingredient in skincare. But not all Vitamin C is created equal.
Most studied and effective form. Use 15-20%. Unstable — oxidizes when exposed to light, air, and heat. Look for opaque or dark packaging.
pH requirement: Below 3.5 for penetration. This is why it can sting.
Stable derivative. Gentler, less irritating. Converts to L-ascorbic acid in skin. Good for sensitive skin. Use 5-10%.
Oil-soluble derivative. Penetrates deeper into skin. Very stable. Works at higher pH (less irritation). Premium formulations use this.
Stable, gentle, water-soluble. Converts slowly to active form. Good entry point for sensitive skin.
💡 How to tell if your Vitamin C has oxidized: It turns yellow, then orange, then brown. If it is dark yellow/brown, it is no longer effective and may actually harm your skin. Toss it.