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#SkinSchool: The best best vitamin C serums, and exactly how they work
It's a commonly-used ingredient in skincare formulas, but is this powerhouse worth the space in your routine?
By now, the skincare benefits of vitamin C have been widely extolled: this powerhouse antioxidant has the ability to brighten skin, neutralise free radicals, and fade acne scars and hyperpigmentation. Consequently, it's safe to say that many of us can benefit from incorporating one of the best vitamin C serums into our daily routines.
Yet reaping the benefits of vitamin C (also known as ascorbic acid), is not quite as easy as slathering on a face serum and waiting eagerly for your radiance revival. Here, we reveal everything you need to know about harnessing its potent potential in full, as well as the best vitamin C skincare for the job.
Vitamin C products: the Bazaar top five
Best vitamin C serum for brightening
SkinCeuticals C E Ferulic Antioxidant Vitamin C Serum
Read review
What is vitamin C and how does it work?
Vitamin C is the primary antioxidant in human skin, and is an essential nutrient for good health, explains aesthetic doctor and educator in cosmetic dermatology Dr. Amiee Vyas. “It is required for many bodily functions including the production of collagen – a vital component in many of our tissues, from skin to ligaments and tendons, cartilage and bone, and even the corneas in our eyes.” As vitamin C is water soluble and not stored in the body, we need to obtain it from external sources: through food and topical application.
What are the benefits of vitamin C serums?
Whether you're looking for a straightforward formula or one laced with extra actives, there is a vitamin C out there for you. Dr Vyas explains the benefits of incorporating a vitamin C serum in your routine.
- It delivers a photoprotective, antioxidative, anti-pigmentary and overall anti-ageing effect.
- It can promote collagen and elastin production, as well as reduce collagen damage in the skin’s dermis. This results in firmer, smoother and more resilient skin.
- It's an anti-pollution powerhouse. As a potent antioxidant, it can neutralise free radicals from pollution, UV radiation and blue light, plus other aspects of our daily lives.
- It can help fade and prevent dark spots, or hyperpigmentation. Vitamin C reduces melanin production through its action as a tyrosinase inhibitor, brightening skin and preventing oxidation of existing pigmentation so it doesn’t become darker.
Which skin types should try vitamin C?
“Non-sensitive skin types with a strong skin barrier can benefit best from vitamin C skincare," says Dr. Vyas. In fact, most of us looking to brighten skin, prevent wrinkles or fade pigmentation should be on board with this brilliant ingredient.
"However, be careful with sensitive skin and fragile skin barriers,” she cautions, highlighting dry skin conditions such as eczema, dermatitis and rosacea as potentially problematic. “I always recommend a patch test if you have any of these. It’s better to strengthen your skin barrier using other ingredients first. This is because most topical treatments have a pH of around two (very acidic), which can cause flare-ups of conditions like eczema, and even acne.”
When should you use a vitamin C serum?
A vitamin C serum should be used daily, and optimally as part of your a.m. skincare routine, says Dr. Ashwin Soni, a leading plastic surgeon, aesthetics expert and founder of The Soni Clinic. "It should be applied after cleansing and prior to your day cream and SPF."
Often, "some new generation vitamin C serums are formulated with other antioxidants, such as niacinamide, for enhanced protection against free radical damage from external stressors such as UV and pollution," Dr. Soni notes – "therefore you really want to use it in the mornings".
Ideally, it should be used consistently, Dr. Soni continues. "As vitamin C is used to protect against accelerated ageing, we want to use it daily."
Is vitamin C a stable active?
Vitamin C is notoriously unstable as an ingredient, meaning heat, light and air can easily degrade its efficacy. For this reason, it pays to delve a little deeper into formulations and packaging, to ensure you’re getting a potent concoction with longevity.
Vitamin C isn’t the easiest ingredient for the skin to absorb either. “Being water-soluble it's repelled by our waterproof skin barrier. It is only absorbed by the skin when the pH level of the formula is below four," explains Dr. Vyas.
How to choose the right vitamin C serum
- Look for products in airtight, opaque packaging to keep the formula fresh.
- L-ascorbic acid is the most commonly used form of stable vitamin C. Other stable vitamin Cs worth looking out for are tetrahexyldecyl ascorbate, 3-O ethyl ascorbic acid, and ascorbyl tetraisopalmitate.
- Consider your skin type. Oily and combination complexions should look to lightweight gel or water textures while those with dry skin will want a more hydrating formula.
- Look at the formula as a whole; ingredients such as vitamin E, ferulic acid, peptides and niacinamide will help improve the efficacy of your product.
The best vitamin C serums to try now
A firm favourite within the Bazaar beauty team, this lightweight serum by Sarah Chapman brightens using a combination of oil and water soluble forms of vitamin C for better skin penetration.
Niacinamide helps to rebalance excess oil while tranexamic acid keeps pigmentation spots at bay. The brand's new TTS3 technology features an encapsulated delivery system that ensures optimum ingredient absorption. One Bazaar beauty editor noticed significant results on her acne scars after using one bottle.
Revision Skincare C+ Correcting Complex 30%™
Aside from tackling pigmentation and protecting skin from the elements, this hydrating serum also contains prebiotics to help minimise any redness. If your skin tolerates vitamin C but is prone to inflammation, this could be the product for you; it works wonders on any signs of flushing. The texture is slightly heavier than a watery serum, so those with combination-to-dry skin will benefit best.
La Roche-Posay is always a good place to start when you're incorporating a new active into your regime. With a lightweight texture, this gentle serum combines hyaluronic acid, salicylic acid and vitamin C to clear congestion and keep the skin barrier hydrated.
As vitamin C serums can be strong, it's worth investing in a targeted formula for use around your eyes. If you're prone to milia, it's also a good idea to choose something light and watery in texture. Medik8's brightening essence ticks all the boxes: it's gentle, absorbs instantly, and layers well beneath make-up.
SkinCeuticals C E Ferulic Antioxidant Vitamin C Serum
This cult classic has been praised by beauty editors for years, but new clinical research really solidifies its effectivity when it comes to protecting the skin. A 2023 study has shown C E Ferulic to neutralise 48 per cent of free radicals that reach the skin before they have a chance to induce inflammatory damage.
The water-light formula contains 15 per cent pure l-ascorbic acid alongside calming vitamin E and ferulic acid, which helps to stabilise the vitamin C, ensuring optimum potency. It's praised in particular for its ability to brighten pigmentation in darker skin tones.
If you're looking for something to treat oily and acne-prone skin, the brand's Silymarin CF serum is equally brilliant. It brightens just as well as the original, but is blended with milk thistle to regulate oil production and bring enlarged pores back to their natural size.
The cult of Cerave is (rightfully) strong, and the dermatologist-loved brand is building its fanbase further with a line of active treatment serums. The latest is a simple yet highly effective vitamin C serum, bolstered by hyaluronic acid for hydration and the brand's signature ceramides to keep the skin barrier strong. It's already the top-selling vitamin C product in the US, and we're sure it'll find the same success on home soil.
The latest innovation in Dr Sam Bunting’s excellent skincare repertoire is much more than a vitamin C serum (although with a 15% vitamin C complex, it promises all the benefits outlined above). In it, you’ll also find 5% SSE (a.k.a. breakthrough ingredient sunflower shoot extract – which boosts NAD+ levels in the skin, triggering DNA repair) and 2% ectoin, the environmental shield everyone’s seeking for its ability to protect and repair your skin. Consider it vibrancy in a bottle.
Allies of Skin 20% Vitamin C Brighten + Firm Serum
A beauty editor favourite, Allies of Skin creates precise products designed to bring about targeted skin changes. This vitamin C serum contains 20 per cent l-ascorbic acid – so may need building up to – but makes light work of fading hyperpigmentation and brightening uneven skin texture.
The milky gel texture feels dense and thick at first pump, but spreads easily on the face and absorbs to leave skin feeling silky and hydrated. If you're not especially sensitive, and looking for a potent product to deliver quick results, this may be the one.
Leading facialist Fatma Shaheen treats some of the most photographed faces in the business, and this summer she has introduced three clinic-strength peels into her own at-home product line, Skin Design London.
A must-try for anyone with sun spots and even melasma, the C-Glow Peel combines stable vitamin C with phloretin and an innovative active called Radianskin, which inhibits melanin production to prevent future pigmentation from coming to the surface.
Dr. Dennis Gross 15% Vitamin C Firm & Bright Serum
A brilliant hyperpigmentation serum, Dr. Dennis Gross' offering contains a high dose of ascorbic acid alongside lactic acid, which exfoliates the skin surface, and liquorice, which bolsters the brightening powers. While we wouldn't recommend this one for the extremely sensitive, it's garnering rave reviews for the way it speedily rejuvenates dull, uneven skin.
L'Oréal Paris Revitalift Clinical 12% Pure Vitamin C Serum
"My preferred vitamin C is the L'oréal Revitalift – for the price point and also the activity of the vitamin C in it, it's probably one of the better ones on the market," says dermatologist Dr Anjali Mahto.
Indeed, this high-street serum is impressively formulated, with 12% L-ascorbic acid alongside salicylic acid to keep blemishes at bay.
This excellent value vitamin C serum contains some stellar supporting ingredients frequently found in the most premium formulas. Alongside the L-ascorbic acid sits brightening peptide glutathione and a cocktail of resurfacing fruit enzymes, all of which work together to brighten dull skin swiftly.
As consumers demand active products that work on the skin beyond the neck, plenty of innovative new formulas are landing on the shelves, from retinol body lotions for intense rejuvenation to brightening powerhouses, such as Nécessaire's new launch.
Vitamin C is one of several actives in this lightweight serum: along with tranexamic acid, enzymes and niacinamide, it'll work to brighten pigmentation and fade surface marks in a matter of weeks.
