Vitamin C is one of those ingredients we’ve all heard of, but chances are, you only know the half of it. For starters, vitamin C is found in more than just oranges. In fact, the Australian native ingredient Kakadu plum contains 100 times more vitamin C than an orange and is one of the world's highest sources of vitamin C. Vitamin C is also so much more than a skin-brightening superhero. Here’s everything you need to know about the popular skin care ingredient, plus our favourite vitamin C serums for brighter, younger skin.
What is vitamin C?
“Vitamin C, also known as ascorbic acid, is a potent antioxidant that is renowned for its benefits across a wide range of skin concerns. It is also one of the most researched active ingredients used in skin care for protection against photoageing, evening out the skin tone, and promoting more youthful-looking skin,” says Prudvi Kaka, Chief Scientific Officer at DECIEM.
Vitamin C benefits for skin
So what does vitamin C do for the skin? We suppose the question should really be what can’t it do, because the benefits of vitamin C for skin are wide-spread. “Vitamin C has the ability to neutralise free radicals, including those induced by excessive exposure to ultraviolet radiation,” says Kaka. “In addition to that, vitamin C plays a major role in recycling antioxidants that are naturally present within the skin, such as vitamin E and glutathione. Vitamin C helps to regenerate vitamin E and together they work in conjunction to provide photo-protection to the skin.” But hold up, there’s more. “Moreover, vitamin C helps to preserve existing collagen by influencing the enzymes responsible for its degradation. Various clinical research demonstrates the ability of vitamin C to encourage the proliferation of dermal fibroblasts. This in turn promotes collagen production within the skin, which would reduce the appearance of signs of ageing and enhance the look of smoother skin texture,” explains Kaka.
So we guess you could say it’s a pretty vital ingredient in your skin care line-up. You know, if you’re into looking younger and protecting your skin from future damage.
Who should be using vitamin C?
“Given its multifunctionality, vitamin C can be used by a wide range of skin types and can be used to address several skin concerns,” notes Kaka. “For those with younger skin, vitamin C can be used to provide antioxidant support as a preventative measure from the damaging effects of oxidative stress and excessive exposure to UV radiation in the long term. For those with ageing skin who are experiencing visible signs of ageing, such as fine lines and wrinkles, vitamin C is a great skin care ingredient to use to help promote the look of smoother, youthful skin.”
In summary - we all should be using vitamin C. But, start off slow and work your way up to regular use, as some skin may be sensitive to the active ingredient.
What percentage of vitamin C is best?
“When it comes to functional ingredients like vitamin C, percentage is commonly misconceived as denoting the level of efficacy i.e. the higher the percentage, the better the results. The reality is that there are many factors involved when it comes to delivering the claimed benefits of vitamin C,” says Kaka.
“It is important to take into account that exposure to UV radiation, plus, the half-life of vitamin C affects the level of vitamin C within the skin. For instance, when the skin is exposed to UV radiation, the concentration of vitamin C depletes as it is being used up for photoprotection purposes,” she explains. “Unless you have sensitive skin, you should ideally have a decent percentage of vitamin C within your regimen.”
“One must also take into consideration the format of the formulation in which the active is incorporated in. For instance, vitamin C oxidises rapidly when present in an aqueous formulation [a formula that contains water], which may reduce its efficacy. In addition to that, vitamin C has an increased stability and better transportation across the stratum corneum in formulations below a pH of 3.50 or when present in anhydrous (water-free) formats,” says Kaka.
Choosing the right concentration of vitamin C
“When it comes to choosing the right concentration, we recommend starting at a low concentration of vitamin C and working your way up to higher concentrations. This would not only ensure the build-up of vitamin C reservoir within the skin, but will also help to gradually increase your skin’s tolerance to the potency of vitamin C,” recommends Kaka.
What you need to be careful of when using vitamin C skin care
“As vitamin C has an acidic pH, it is important to take into consideration skin sensitivity. If your skin is not familiar with acidic ingredients, we always recommend a patch test prior to facial application,” suggest Kaka. “Subsequently, based on the results, you may prefer to start using vitamin C at a low concentration, then work your way up to higher concentrations as your skin develops its level of tolerance.”
“We do not recommend using more than one [vitamin C] product in a single regimen as this may enhance or induce skin sensitivity,” adds Kaka.
A note about mixing vitamin C with other ingredients
“When it comes to mixing vitamin C with other functional ingredients, it is important to remember that vitamin C has a low pH value (due to it being an acid) and a powerful antioxidant capacity,” says Kaka, who notes that these two factors may affect the stability or integrity of other ingredients. “For example, we do not recommend combining niacinamide with vitamin C products as the acidic conditions may induce the production of niacin, which may cause flushing. Furthermore, we do not recommend combining vitamin C with peptides as its acidity may increase the susceptibility of the peptides to hydrolysis. It is also our understanding that copper ions can accelerate the oxidation of vitamin C. In this instance, copper ions have the potential to interact with the vitamin C and cause its colour to change from colourless to dark orange. Therefore, we would not recommend combining vitamin C with other products containing copper ions,” says Kaka.
Can you over-use vitamin C?
We get it - vitamin C is a pretty amazing ingredient so it can be tempting to practically bathe in the stuff. But Kaka warns about over-using the ingredient. “In the case of vitamin C, there are indicators that one can look out for as a sign of overusing the ingredient. For instance, when it comes to suspensions of pure vitamin C, they are gritty upon application at first, but over a short period of time, the moisture within the skin solubilises the powder particles and the skin draws the vitamin C in. However, when applied in excessive amounts, a gritty residue will continue to remain on the skin, which is an indication of over-usage. In addition to that, if the skin’s tolerance to high exposure of pure vitamin C is not developed gradually, a strong tingling but non-irritating sensation may be experienced. If the sensation is too strong to tolerate, we recommend opting for a vitamin C derivative as an alternative,” says Kaka, who suggests vitamin C derivatives such as magnesium ascorbyl phosphate, ascorbyl glucoside and ascorbyl tetraisopalmitate.
8 best vitamin C serums for brighter, glowing skin
One of the best ways to get your vitamin C fix in its most potent form is with a vitamin C serum. It’s where you’ll find the ingredient in a highly concentrated and stable form, which means your skin will reap ALL the rewards. We’ve pulled together a curated list of some of our favourite vitamin C serums for the face.
#8 / Olay Niacinamide + Vitamin C Super Serum
Hitting shelves in February 2021, Olay's innovative new release allows you to reap the benefits of both niacinamide (vitamin B3) and vitamin C in the one serum, eliminating the ramifications that may come from mixing them yourself. Instead, the two vitamins work synergistically together for a more even skin tone and radiant complexion.
#7 / Tatcha Violet C Brightening Serum
If you’re after a refined complexion this serum is your one-stop shop. The impressive formula features two types of vitamin C, as well as Japanese Anjelica Root to fight against discolouration, plus the addition of powerful AHAs, that slough away dead skin cells to reveal brighter and luminous-looking skin.
#6 / Dr. Dennis Gross C+ Collagen Brighten + Firm Vitamin C Serum
A plumping and brightening wunderkid, this vegan-friendly option from Dr. Dennis Gross combines the power of vitamin C with collagen for a potent anti-ageing formula. Featuring a touch of lactic acid, this little guy also helps to gently resurface dull looking skin for an overall healthy-looking glow that’ll leave you gleaming just in time for summer.
#5 / Sunday Riley C.E.O 15% Vitamin C Brightening Serum
Arguably one of the most popular vitamin C formulas on the market, Sunday Riley’s famous C.E.O serum is known for being a powerhouse at minimising the appearance of hyperpigmentation. A great choice for those who suffer from discolouration from sun exposure or melasma.
#4 / The Ordinary Ascorbyl Glucoside Solution 12%
Taking out the drugstore category for our pick of the best vitamin C serum, this lightweight brightening and anti-ageing formula contains a stabilised and water-soluble vitamin C derivative known as ascorbyl glucoside, which is highly stable and comfortable to use. If you’re looking for something effective that won’t irritate your skin, give this one a try.
#3 / La Roche-Posay Redermic Pure Vitamin C10 Serum
Vitamin C has been paired up with other top-performing ingredients in this serum to bring you effective results in a non-irritating formula. Safe for sensitive skin types (La Roche-Posay is known for its gentle formulas), 10 per cent vitamin C along with exfoliating salicylic acid and soothing neurosensine all work together to stimulate collagen and elastin production and strengthen the skin’s defence against daily aggressors so you’re left with skin that’s smoother and firmer with a healthy glow.
#2/ Drunk Elephant C-Firma Day Serum
This vitamin C serum is one of the hero products in the Drunk Elephant line-up, and has gained a cult following for its potent formula. Visibly brightening and firming skin with the help of vitamin C, it also contains enzyme exfoliants pumpkin ferment and pomegranate extract, which dissolve dead surface skin cells and minimise the appearance of pores.
#1 / Skinceuticals C E Ferulic
Beauty editors around the world are obsessed with this vitamin C serum because it’s that good at targeting all kinds of skin woes - including discolouration, dryness, lines and wrinkles, and sensitised skin - and leaving a bright, smooth and healthy complexion in its wake. You’ll find 15 per cent pure vitamin C (L-ascorbic acid), one per cent pure vitamin E and 0.5 per cent ferulic acid in this potent serum. It doesn’t come cheap, but we think it’s worth every cent.
Chelsea is BEAUTYcrew’s Contributing Editor. She has a sweet spot for anything that claims to make skin glow and won’t leave the house without a slick of mascara. Chelsea has 10 years of experience as a beauty editor and her words can be found on BEAUTYcrew, Women’s Health, Daily Addict, The Joye and Primped.