Vitamin C without the sting

Ask around and most people have a vitamin C story. It tingled. It turned orange in the bottle by March. It smelled, faintly but unmistakably, of a handful of old coins. Then it went into a drawer, and the drawer kept it.

None of that means vitamin C is a bad idea. It means the most famous form of it is hard work.

The fussy one and the steady one

Pure vitamin C, ascorbic acid, is a strong antioxidant and an unstable molecule. Light, air and warmth break it down, and as it oxidises it changes colour and smell. To work on skin it also needs a very acidic formula, which is where the tingle comes from.

Ascorbyl glucoside is vitamin C with a glucose molecule attached. That small change keeps it stable in the bottle and gentle on the skin, where the glucose is gradually split off. You trade a headline-grabbing number for a steadier antioxidant you can use every day, and an antioxidant only helps on the days you use it.

Why 2%

Strength on a label is easy to sell and hard to live with. We chose 2% ascorbyl glucoside because it is a level people keep using. In a consumer study of 46 people over four weeks, 94% said the serum never stung, and 91% said their skin looked more radiant by the end of it.

2% you use every morning beats 20% in a drawer.

The partner: ferulic acid

Antioxidants work better in company. Ferulic acid, found in the cell walls of plants such as rice and oats, supports vitamin C, so at 1% it shares the front of the label with it. Add 1% sea buckthorn oil to soften and a little hyaluronic acid for moisture, and the serum feels like a light lotion rather than a science project.

Mornings, under SPF

Use it after washing and before sun protection: two pumps over face and neck, then the Sun Stick or the Tinted Sunscreen. The day is when skin meets the most environmental stress, so that is when an antioxidant earns its keep. It also sits happily under the Colour Correcting Stick, if you’re the swipe-and-go type.

If you use a moisturiser, it goes between the serum and the sun protection. Give each layer a minute to settle, which is about as long as the kettle takes.

Kept fresh

The serum lives in an airless pump: no dropper, no air let in each time you use it, nothing touching the formula until it reaches you. It stays the colour it started, and it smells of mandarin from the first pump to the last.

What it won’t do

Vitamin C is an antioxidant, not a sunscreen and not an eraser. It won’t stand in for SPF, and it isn’t there to change the colour of your skin; we’d be suspicious of anything that promised to. What it does, used every morning, is help skin cope with the day and look less tired by the end of the month.

Who it’s for

Every skin type. If yours is easily irritated, start with every other morning for a week, then every morning. If anything stings, rinse it off and stop; with 2% ascorbyl glucoside that’s rare, but skin is personal, and yours gets the final say.

Give it three or four weeks of mornings. The glow builds; it doesn’t arrive overnight.

In plain wordsVitamin C (ascorbyl glucoside): The stable kind: 2% that doesn’t sting or smell of pennies.