WHAT’S THE DEAL WITH…
Vitamin C? Our beauty director myth-busts this skincare essential
Vitamin C is the volatile Mariah Carey of skincare actives. It’s one of the few guaranteed to improve the state of your skin – a good vit C brightens, beats back pigmentation and keeps collagen production from falling off a cliff. What’s a “good” one? That’s the $64 question. In the wrong formula, vitamin C keeps skin healthy but has few visible results. If you’re going to pay big for a product with an impressive-sounding dose of this diva vitamin, you need your nerdy specs.
Hit me… Ascorbic acid is the active vitamin-C molecule that does all the work. You want to spot it on your ingredient (INCI) list (any = good, 10-15% = optimal). Other “ascorb”-containing terms need converting to ascorbic acid in the skin. This process leaves only a small percentage of active that has little transformative power.
What else? Water oxidises (ie kills) ascorbic acid in days (you’ll see your serum go from clear to orange-y), so ideally you don’t want “aqua” on your INCI list at all. If there is any, look for antioxidants (such as vitamin E) to slow the degradation, and use it up in weeks. Apply your vit C in the AM (it fights off UV damage) and top with an SPF moisturiser. Any downsides? Pure ascorbic must live in an acidic formula to work, so it can sting and cause uneven pigmentation on darker skins. The next best choices (which don’t break down in water – bonus): tetrahexyldecyl (THD) ascorbate (potent despite requiring conversion) and ethyl ascorbic acid (doesn’t oxidise and doesn’t need conversion).