A Dermatologist Explains How To Use Vitamin C
A Dermatologist Explains How To Use Vitamin C

A Dermatologist Explains How To Use Vitamin C

Vitamin C is known to fend off free radicals that can cause premature ageing, but dermatologist Dr Justine Hextall will tell you it’s also capable of so much more. Commonly found in serums, face masks and moisturisers, this hero ingredient also boosts collagen and is one of the few proven to brighten dullness and even out skin tone. Here, we asked her to tell us more about why and how you should be using it.
By Rebecca Hull

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It’s Been Dubbed A ‘Powerhouse’ For A Reason

“Vitamin C is a highly effective antioxidant. What that means is it protects – better than most other skin ingredients – against external aggressors like pollution and UV, both of which speed up the ageing process. It also interferes with and suppresses enzymes that create pigment in the skin, so it’s essential for anyone who wants to reduce uneven tone and dark spots. Regular use boosts your natural collagen production, too. In other words, it’s a great all-rounder.”

Regular Use Protects Your Skin’s Barrier

“The ingredient works hard to neutralise and remove oxidants from the skin that are seen after exposure to UV radiation. It also plays a part in cell signalling, supporting keratinocyte cells to improve the structure of your skin’s barrier. The result? A complexion that looks healthier and feels smoother. Vitamin C also helps boost your skin’s barrier lipids – these are full of moisture and, again, are vital to maintaining a healthy barrier function.”

Stable Formulas Are Best 

“It’s worth noting that vitamin C can be ‘unstable’. What I mean by this is certain types can be degraded by heat, light and even from contact with the air, which is why you’ll find vitamin C is housed in darker packaging. For maximum efficacy, it’s key you buy vitamin C – whether that’s in a serum, cream or mask – that states it is ‘stable’ and you can often find this out on the label. Regardless of which product you choose, always store it in a dark space away from heat and light once opened.”

Not All Vitamin C Is Created Equal

“There are different forms of vitamin C, so it pays to swot up. The most potent is ascorbic acid, but this is an unstable form as it oxidises once exposed to air. It can, however, become more stable if you’re combining it with other antioxidants, including ferulic acid and vitamin E – both increase its efficacy. More stable forms of vitamin C include magnesium ascorbyl phosphate (MAP) which is less potent but gentler for sensitive skin. You also have sodium ascorbyl phosphate (SAP) which comes with antimicrobial benefits. Finally, there’s ethyl ascorbic acid (EAA) which has been shown to have superior brightening effects to ascorbic acid. It’s a balance between stability, efficacy and tolerability, and ultimately it must work for you. It’s also worth noting that there’s little evidence that increasing your vitamin C % enhances efficacy, so remember you don’t have to go high to see results. If anything, you may end up just irritating your skin. I often recommend a maximum of 5%.”

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Application Is Best First Thing

“If you apply your vitamin C in the morning – alongside SPF – you know you have an extra layer of protection against pollution and UV. The only downside is vitamin C isn’t photostable, which means it becomes less effective with light exposure, so if you work outside a lot it may be best to apply it at night instead. Typically, I suggest vitamin C in the morning and, if you need one, a retinol at night.” 

You Can Expect Results Quite Quickly

“Vitamin C is an active ingredient so, when used correctly and sensibly, you can expect to see results within weeks. I’ve certainly seen changes in clients’ skin quite quickly. It is key you keep your application consistent – dipping in and out of application won’t allow for the same effects. It can cause sensitivities, so it’s key you build up your tolerance gradually – alternating days to begin with – so that you stick to a routine and don’t give up on it too quickly. That said most vitamin C-based products are very tolerable now, with many formulas dedicated to sensitive skin types.” 

There’s One Key Myth To Note

“I know many people who feel that a topical application of vitamin C is of no value if they’re following a healthy diet. While there is no substitute for the latter, it’s actually very hard to get vitamin C through diet and supplements, so what you put in won’t have much of an impact on your skin. It’s why a topical remedy is so important. If you only have money to invest in a few ingredients, I will always say it should be a vitamin C, a retinol and a hyaluronic acid – or better still, a formula that combines each.”

Vitamin C Works Even Better With Certain Treatments 

“I once looked after a young woman who had melasma for years. She had treated it several times before with prescription retinoids and hydroquinone, but it always reappeared. I finally treated her with a mixture of in-clinic peels, microneedling and vitamin C creams. I taught her the importance of avoiding the sun and layering CE Ferulic – one of the best vitamin C serums you can buy – under a high level of SPF protection. After three years, her skin is still clear of melasma. A mixture of treatments can give you satisfying outcomes – especially if you’re particularly concerned over pigmentation at a deeper level.”

Serums Are Most Effective 

“The best type of vitamin C skincare product to use is a serum. You’ve likely heard it before, but the thinner texture often means serums deliver more potent ingredients more effectively than creams or toners. I recommend adding some vitamin E into your routine alongside your vitamin C – the two work well together to boost suppleness, skin tone and overall, create a healthier, happier complexion. Together, the two can double the protection against free-radical damage.”

For more skincare advice & to book an appointment with Justine, visit JustineHextall.co.uk


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