It’s deemed ‘essential’ by dermatologists, but why, when and how should you be using vitamin C? Here’s your guide to one of the most powerful antioxidants on the planet…

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Vitamin C- as health and wellbeing goes, it’s a big hitter. You could call it an award-winning antioxidant, given that Dr Albert Goyrgi won the Nobel prize in 1937 for identifying a lack of it as the principal cause of scurvy, and as such, it’s also far from a new skincare fad in the vein of snail slime and unicorn juice. Much researched and respected for its skincare prowess, vitamin C seems to be having a moment in the sun currently in the beauty industry, with buzzy launches aplenty and a proliferation of bright orange packaging popping up on shelves. Add to this the fact that, according to Mintel, 85% of consumers are either likely to be using, or interested in using, beauty and skincare products containing vitamin C, and it becomes clear that our thirst for the potent antioxidant shows no sign of waning.

Just why, however, is it so feted in skincare circles, scurvy aside? Does it merit the demand, and how do you know if it’s working? Is vitamin C for all? Read on for the vit C commandments…

It lives up to the hype

Just to clarify from the outset, vitamin C is universally agreed to a very good thing for all skins. Its profile has been on the up since the 1930s it seems, and its acclaim of late owes as much to our modern lifestyle as it does scientific advances, as Dr Anjali Mahto, consultant dermatologist at the Cadogan Clinic , explains:

“The benefits of vitamin C have been known for some time, but are definitely coming more to the forefront lately. This may be because we’re much more aware of our environment and the way it’s affecting our skin – we’re a lot more aware of environmental pollutants  such as radiation, sunlight, cancer-causing free radicals and smoke, which break down collagen , stressing the skin and accelerating the ageing process. As vitamin C helps to counter that process and can be used to treat such a variety of issues, it’s become a bit of a hero ingredient.”

Oculoplastic surgeon, aesthetic doctor and founder of  MZ Skin  Dr Maryam Zamani  also emphasises that its reputation has been enhanced by its proven anti-ageing rigour and our increased knowledge as to how to handle the sensitive vitamin:

“I think that now that vitamin C has been tried and tested with efficacious results to treat discoloration while promoting collagen synthesis with a low risk profile, we are seeing a surge in products that contain vitamin C in skincare lines. We also understand that uneven skin tone is an important factor in ageing skin, and as an ingredient that helps create a more even skin tone with a low risk profile, vitamin C has gained increased popularity. And finally, we are now able to maintain active vitamin C in skincare to allow it to work more efficiently.”

It’s an all-rounder

If vitamin C were at school, it would for sure be a prefect, captain of the netball team and in possession of a clutch of A*s and an Oxbridge acceptance letter. Dr Mahto underlines why it’s top of the class in terms of skincare ingredients to prioritise:

“Vitamin C is an absolute essential for your skincare regime, because as well as being a potent natural antioxidant, it has anti-inflammatory properties, can act as a depigmenting agent and is vital for collagen biosynthesis . It is often used in dermatology to treat and prevent the signs of ageing caused by ultraviolet radiation.”

Dr Zamani seconds this, with bells on:

“Vitamin C boosts collagen to keep skin looking firm and young, it protects against free radicals to prevent premature ageing, it fades dark spots and brightens the skin and it can even boost your sunscreen's protection”

If you were previously in any doubt about recruiting vitamin C into your skincare dream team, this should seal the deal. If you’re wondering when to crack on, the next point should clear that up…

All ages should use it

Vitamin C doesn’t discriminate- it both helps to prevent skin deterioration in the first place, and aids in the repair of damage once it’s done. In short, it’s sickeningly helpful, as Dr Mahto confirms:

“Vitamin C can be incorporated into your skincare routine at any age, in fact, the earlier the better. As well as being an anti-ageing skincare ingredient which generally helps to gently brighten and smooth your skin, it's one of the most powerful antioxidants out there. Regularly applying vitamin C within your skincare routine helps to protect your skin against free radical damage caused by the environment, which can breakdown your collagen and encourage wrinkles and sagging.”

If you’re noticing some particular skin niggles now, Dr Zamani especially encourages concentrating on adding vitamin C to your bathroom cabinet for its skin-improving effects:

“Even though signs of ageing and  pigmentation  might not appear until you're into your thirties, it's good to start using vitamin C when you start seeing the signs any time after 18 years old. These might be brown spots  on the skin from sun exposure, skin losing its glow, and red marks following a breakout which refuse to fade.”

You’ve committed to adding it to your bathroom cabinet, but in the plethora of citrus themed products out there, what exactly should you be looking for?

Watch out for potency and packaging

A Sunny Delight scent and jazzy bottle clearly speak nothing of a product’s effective vitamin C content. To ensure you’re hitting the sweet spot it terms of vitamin C that actually works, heed the pros’ advice. Dr Zamani gives us the numbers:

“When looking for a suitable Vitamin C product, finding the right concentration is important. A potency of 10-20 per cent means that results for the skin will be seen quicker and more uniformly across the skin. The way the vitamin C is produced is a key factor in how efficacious its will be on the skin.”

“A concentration of between 3 and 10 per cent will still be effective, in an L-ascorbic acid or ascorbic acid form. Vitamin C can break down in UV light and lessen its potency, so I recommend that packaging is sealed and kept in a dark environment.”

Dr Mahto also tips us off on the fact that super doses of vitamin C won’t necessarily pay off:

“Maximum skin absorption of vitamin C occurs at 20% strength. Increasing the concentration beyond this limit does not result in greater skin absorption. Using agents with relatively high concentrations such as 10-15 per cent or more are likely to have the most benefit but also run the risk of causing skin irritation.”

Read the label

This is fast becoming a mantra for modern life, but identifying vitamin C in its many guises, and where it sits in  a product’s ingredients list  (high= the real deal) will help you to separate the vitamin C superstars from the imposters. Dr Mahto has your vitamin C phrasebook at the ready:

“Any type of vitamin C in your moisturising serum and lotion will likely offer some skin benefit. There are several different types of vitamin C used in skincare products, so you want to look out for things like L-ascorbic acid, sodium ascorbyl phosphate, ascorbyl palmitate and retinyl ascorbate on the ingredients label. Retinyl ascorbate has the most amount of scientific research surrounding its benefits and L-ascorbic acid helps to boost collagen production and smooths and firms skin, as well as preventing photo-ageing.”

“Other ingredients you should look for in vitamin C products include magnesium ascorbyl phosphate (this is the most stable and preferred vitamin C compounds), disodium isostearyl 2-0, L-ascorbyl phosphate, ascorbic acid sulphate and tetraisopalmitoyl ascorbic acid. The effects of topical vitamin C can also be enhanced by other agents such as ferulic acid and vitamin E.”

Investing in a skincare product that combines vitamin C with its helpful henchmen can result in even better skincare results. Dr Zamani highlights what the likes vitamin E can bring to the vitamin C party:

“Vitamin C can be combined with anti-ageing, UV damage fighting antioxidant vitamin E, or hyaluronic acid, which penetrates into the dermis boosting the elasticity and hydration of the skin. The protective barrier on the skin locks in moisture, which gives the skin a youthful appearance. It is also often combined with ferulic acid, a powerful antioxidant that combats the free radicals in your skin.”

You’ve got your product mixology down, but of the myriad of formulations out there, should you opt for a cream, mask, wash or another specific treatment?

Some delivery methods are better than others

In other words, there’s only so much C you can get if you’re washing a vitamin-rich product down the sink. The experts agree that one delivery method in particular excels above the rest. Dr Mahto gets real:

“Vitamin C is available on the market in a variety of creams, serums, and transdermal patches. Of these formats, it is usually the serum that contains active vitamin C.”

Truth serum is where it’s at, and Dr Zamani is in agreement:

“Serums are a concentrated way to get anti-aging ingredients into the skin which can then be layered with other products with no interference.”

Before you spend big on said serum, make sure it’s gone belt and braces in terms of high quality formula and physical delivery. Packaging serves a more important purpose that it’s given credit for in the skincare sphere:

“Vitamin C is an unstable molecule which oxidises quickly on exposure to light. Its stability is usually maintained by keeping a low (acidic) pH of less than 3.5. Not all vitamin C derivatives are physiologically effective so it can be helpful to check product ingredients. It's also worth noting that when antioxidants are exposed to light and air too frequently they can break down, so it's best to opt for formulas in air-tight packaging, pumps or single-use, individually wrapped products.”

It’s a morning vitamin

In general, you’ll get the most out of vitamin C in the morning. Dr Zamani supports the early bird catching the skincare worm theory here:

“Because vitamin C serum helps to shield your skin from free radicals and can help to boost the protection offered by your sunscreen, it is recommended that you apply it in the morning to prevent damage to the skin during the day- once a day is fine but I recommend it twice daily. It should go without saying that the application of sunscreen on top is essential.”

There’s growing evidence that applying at night time too won’t hurt, as Dr Mahto reveals:

“Some research suggests that free radical damage continues to affect your skin overnight, so you could add in vitamin C to your end of day routine as well.”

Just bear the following in mind before you apply willy nilly...

It’s got a few enemies

Just to bring back the school playground analogy, vitamin C isn’t best pals with all of the ingredients in your skincare repertoire. According to Dr Zamani there are a few notable incompatibilities  which could provoke adverse reactions such as stinging and redness:

“Active ingredients in skincare have different purposes and using them at the same time as vitamin C in high concentrations may result in irritation. It's best to avoid retinol, glycolic, salicylic and lactic acid when using vitamin C or to gradually implement these actives to produce less visible skin irritation.”

Go easy on the acids , but Dr Mahto notes that certain skin types may also find other ingredient combinations troublesome:

“Besides vitamin C induced irritation, some people breakout from vitamin C products because of their base. For example, some vitamin C serums may contain silicones or other inactive ingredients (to help keep the vitamin C stable longer) that can be problematic for acne-prone or sensitive skin, so make sure you read the ingredients thoroughly.”

Still struggling to show face after a vitamin C session? Dr Zamani advises ‘baby steps’ for beginners:

“Vitamin C is formulated at a low pH which can be irritating to the skin and cause flaking. You can avoid these side effects by using it properly; don’t start off using the strongest serum, you can work up to it.”

Wondering how? See below for your handy vitamin C skincare shopping list.


No7 Youthful Vitamin C Fresh Radiance Essence , £19.50

A two week vitamin C ‘course’ rather than a serum per se, this gel like elixir has an element of the DIY about it- you click of the cap of a 5% strength vitamin C powder and shake it together with the essence (which incidentally also contains vitamin B) to make a stable solution, although it’s vital to keep your bottle away from light.

Repavar Active Vitamin C Ampoules , £21 for 20 capsules

Lightweight, oil-free and fragrance-free and with 5.5% ascorbic acid, this is a gentle, easy way to slip vitamin C into your daily routine in the perfect dosage. Snap off the top, smooth under your usual skincare and go.


Clinique Fresh Pressed™ Daily Booster with pure Vitamin C 10% , £58 for a month’s supply

Another ‘course’ lead vitamin C option, the month-long Fresh Pressed™ booster pack was favoured over the range’s powder cleanser option in terms of return on investment in the radiance stakes. Our tester noticed a difference in terms of brighter, healthier looking skin in a week (which was as promised by the brand) by mixing it with moisturiser AM and PM, and the nifty packaging isolates a vitamin C powder until you’re ready to use it by shaking it into an emulsion.

Skinceuticals Phloretin CF Gel , £150 for 30ml

Pricy, yes, but Phloretin is prized by the world’s top dermatologists for its status as a superior, scientifically proven topical antioxidant. The serum has a water base, so is particularly suited to oily or breakout prone skin, and the much prized ferulic acid enhances the effects of the 10% strength vitamin C.

MZ Skin Brighten & Perfect 10% Vitamin C Corrective Serum , £255 for 30ml

Dr Maryam Zamani’s very own vitamin C based serum aims to nip pigmentation in the bud in particular, with added azelaic acid and peptides to regulate the pigmentation cycle and inhibit the formation of future dark spots.

Beauty Pie Superactive Capsules Pure Double Vitamin C & E Serum , £50 for 60 capsules or members pay £11.92

Encapsulated  for maximum stability (the orange serum pods are biodegradable), this 10% vitamin C ‘shot’ tingles very slightly when applied, but the fact that it’s combined with moisturising vitamin E in a fragrance-free formula lowers the risk of irritation - just introduce it gradually if you’ve got sensitive skin.

Tandem Brightening Booster , £20 for 30ml

Tandem believes skincare should be simple - why overcomplicate a routine rather than just use a few prodicts that really work? like this serum, for example. For the slightly more advanced vitamin C user, this booster (applied before moisturiser) has two forms of vitamin C; 20 per cent oil-soluble ascorbyl tetraisopalmitate (a format of vitamin C less prone to oxidation than other vitamin C formats) and Australian Kakadu plum (with 55 times more vitamin C than an orange) - a daily dose of this little powerhouse helps stimulate collagen production to brighten up tired, dull skin. It's also blended with squalane to deliver smoothness and softness.


Perricone MD Vitamin C Ester 15 , £79 for a month’s supply

At 15% strength, these four vials give your skin a relatively potent hit of vitamin C in one go (roughly five ‘dabs’ per application), along with small amounts of vitamin E to help it along its antioxidant way. Not cheap, but at this percentage you should notice results in terms of a more unified skintone and texture within the month, as our tester did.

Skinceuticals C E Ferulic , £113 for 30ml

Skinceuticals’ more hard-hitting vitamin C option, the cult C E Ferulic combines 15% L-ascorbic acid with vitamin E and ferulic acid to knock free radicals out of the park/ away from your face. A few drops go far- I eked my bottle out for almost a year.

Drunk Elephant C-Firma Day Serum , £67 for 30ml

This brings the jazz hands to all-day vitamin C action, combining 15% L-ascorbic acid with vitamin E, exfoliating fruit enzymes and hydrating sodium hyaluronate to leave skin smooth and bright from every angle. Plant oils provide additional nourishment which makes this newbie to the UK particularly suitable for dry skin.

The Ordinary Vitamin C Suspension 23% + HA Spheres 2% , £4.95 for 30ml

This one’s throwing the kitchen sink at skin brightening and barrier strengthening with whopping 23% strength powdered L-ascorbic acid and spheres of dehydrated hyaluronic acid added to the formula for additional skin barrier support. Expect tingles, especially within the first fortnight- you may wish to add it to your regular moisturiser in small quantities until your skin is accustomed to the C sensation. Go especially easy if you’re sensitive of skin.

In the dark about retinol?  Check out the skin experts’ guide to another sought-after skin vit

Follow Dr Zamani on Instagram  @DrMaryamZamani , and Dr Mahto on  @DrAnjaliMahto