Vitamin C has a reputation as the brightening ingredient, the one people reach for when skin looks dull or uneven. That reputation is largely earned. It's also one of the most temperamental ingredients on the shelf, and plenty of people give up on it after a stinging first week or a bottle that turned orange in a month. Here's how to get it right.
What vitamin C actually does
Vitamin C works on three fronts. It's an antioxidant, so it helps neutralise the free radicals your skin encounters from UV and pollution during the day. It interferes with excess pigment production, which is why it's associated with fading dark spots and evening out tone over time. And it plays a supporting role in your skin's natural collagen processes, which is where the firmness claims come from.
What it won't do is work overnight. Realistic timelines are eight to twelve weeks of consistent daily use before you notice a genuine difference in tone and brightness.
Morning or night?
Morning, for most people. Because its main job is defending against daytime environmental stress, vitamin C pairs naturally with sunscreen. Applied under SPF, the two work as a team: the antioxidant handles what gets past the sunscreen.
To be clear, vitamin C is not a sunscreen and doesn't replace one. It's a supporting player.
Where it sits in your routine
After cleansing, before moisturiser. The general rule is thinnest to thickest, and most vitamin C serums are light and watery.
A straightforward morning order:
- Gentle cleanse
- Vitamin C serum on clean, dry skin
- Wait a minute or two
- Moisturiser
- Sunscreen
Starting without the sting
Tingling on the first few applications is common, especially with stronger formulas. Persistent burning is not, and it's a sign to slow down.
- Start with every second or third morning for two weeks, then build to daily.
- Apply to completely dry skin. Damp skin increases penetration and irritation.
- Use a pea-sized amount. More is not better, and excess just oxidises on your face.
- If you have reactive skin, buffer it by applying moisturiser first, then the serum.
What to pair it with, and what to keep apart
Vitamin C plays beautifully with sunscreen, hyaluronic acid and niacinamide. The old advice that niacinamide and vitamin C cancel each other out has been largely walked back, and most people can use both without drama.
Where you do want separation is with retinol and strong exfoliating acids. Using them all in one sitting is the fast route to a damaged barrier. Keep vitamin C to your morning and retinol to your evening, and you've solved the problem without giving anything up.
Why your serum turned orange
Vitamin C oxidises when exposed to light, air and heat. A serum that has gone from clear or pale straw to deep orange or brown has degraded, and while it isn't dangerous, it's no longer doing much.
To slow this down, buy smaller bottles you'll finish within a few months, keep the lid closed tightly, store it away from the bathroom window, and choose opaque or dark glass packaging where you can. Some people keep theirs in the fridge, which genuinely helps in an Australian summer.
Who should be cautious
If your skin is very reactive, or you're dealing with active eczema or rosacea, introduce vitamin C slowly or speak to a professional first. Gentler derivatives exist and are often a better starting point than a high-strength L-ascorbic acid formula.
This article is general information only and isn't a substitute for advice from a qualified healthcare professional. If you have a persistent skin concern, please speak to your GP or dermatologist.