Vitamin C: Everything you need to know about the skincare ingredient

All your questions answered on why you need it and the products that deliver results

A gold-standard anti-ageing ingredient, vitamin C also works to brighten the skin and to reduce pigmentation (iStock)

Shopping for skincare can be tricky, with so many products and performance claims being constantly sold to us in branding and marketing campaigns.

However, there are only a handful of ingredients in skincare that have stood the test of time, with clinically proven results that make them worth the money.

These include retinol, hyaluronic acid, peptides, AHAs, BHAs and vitamin C. You’ll see them on many product labels when you start skincare shopping and the reason is simple – they actually work.

While you can find our carefully curated skincare ingredient glossary here, ahead we’ll be deciphering vitamin C, answering why you need it, how to use it and the products we recommend.

You can trust our independent round-ups. We may earn commission from some of the retailers, but we never allow this to influence selections, which are formed from real-world and expert advice. This revenue helps us to fund journalism across The Independent.

Why do you need vitamin C?

“Vitamin C has three big benefits,” says Dr Anjali Mahto, consultant dermatologist at 55 Harley Street.

“It’s essential for collagen synthesis, it helps shield against the damage from UV rays, and it inhibits the production of an enzyme that causes pigmentation, making it really brightening.”

This makes the ingredient a universal winner, as not only is it renowned for its anti-ageing properties, but it also works to even out your skin tone and to protect you from sun damage.

It is also less irritating than other active ingredients such as retinol, making it suitable for all skin types.

How do you use it?

It comes in lots of different forms in skincare, which can be confusing, but ascorbic acid is the one that is backed up by the most research, so if in doubt, that's the type to look for.

It's worth noting that vitamin C is a tricky ingredient – it is difficult to formulate in a way that makes it pleasant to apply to skin, and ascorbic acid breaks down with regular exposure to air and light (to prevent this, choose products that come in airtight, opaque packaging, or are even one-use) – all of which makes it an expensive ingredient, but we’d argue the results are worth it.

You might find you experience mild irritation when you first use vitamin C; if this is the case, start using it three times a week and build up to daily use.

If you use retinol in your skincare regime, it’s best to apply vitamin C in the mornings and retinol in the evenings to minimise the risk of irritation.

While it doesn't make your skin more susceptible to sunburn, it's important to accompany the ingredient with an SPF, as vitamin C is vulnerable to light exposure. Using an SPF should be the last step in your skincare routine as a protective barrier against the sun. Find everything you need to know about sunscreen and UVA rays here.

Which vitamin C products are the best?

In our IndyBest guide to vitamin C products, the Clinique fresh pressed 7-day system with pure vitamin C (Clinique, £25) walked away with the top spot.

A “week-long boot camp for dull and lined skin,” the kit contains two products, a powder and a “daily booster”, both of which contain the brightening ingredient.

This vitamin C kit gave some of the best brightening and anti-ageing results we saw (Clinique)

To apply, empty a packet of the powder into wet hands and massage into skin, leave for one minute and then remove with a flannel. Double up by adding a couple of drops of the “daily booster” to your regular moisturiser morning and evening.

The Ole Henriksen truth serum (Boots, £43) was also highly rated in our round-up. We found that after a few weeks of use, our skin was noticeably less red and brighter.

This fast-acting vitamin C serum, to be applied after cleansing and before moisturising, reduced redness and brightened skin when we tried it (Boots)

It has a delicious, if slightly medicinal, orange scent, that makes it feel good for you before you've even applied it. The light, silky texture little spreads across the face easily, and feels slightly tacky on the skin for the first couple of minutes before it sinks in.

The Banana bright eye creme (Boots, £32) from the same range also impressed us, instantly lifting our eye area and reducing the appearance of dark colouration. Inspired by the banana powder – a make-up must-have which similarly brightens under the eyes – this contains colour correcting pigments, vitamin C and collagen to plump and reduce those pesky eye bags.

Pat gently under the eye to reduce dark circles and eye bags (Boots)

For a brightening agent in your cleanser, the Super Facialist Vitamin C + brighten skin renew cleansing oil (Feel Unique, £10.99) is superb for a daily dose of the ingredient. It works wonders to shift even the most stubborn of mascaras and feels a lot more luxurious than the price tag suggests.

This vitamin C infused cleansing oil leaves skin silky soft, brighter and smoother (Feel Unique)

Simply massage into dry skin to melt down make-up, SPF, dirt and grime from the day, then rinse with lukewarm water or a flannel. As it’s a rinse-off product it won’t have the same potency as a vitamin C serum, but it will add an instant brightness to your skin before you finish the rest of your routine and go about your day.