The best vitamin C serums to brighten, tighten, smooth and make skin oh-so-happy

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  • Brighter skin days right this way

    Ask any beauty expert or dermatologist what their absolute-must-haves are in their skincare routine and this is what you’ll hear: facial sunscreens, retinol and vitamin C serums.

    Why? It’s pretty simple. When used alongside each other, these three are your skin’s best chance at fighting the visible signs of ageing. Not only that, but this holy trinity also promotes happy, healthy and well-functioning skin. You’ve probably got your best SPF moisturiser at the ready and you’re clued up on which retinol serum works best for you, so now it’s time to look a little closer at vitamin C.

    What does vitamin C do?

    Vitamin C is something of a mega multitasker in the skincare world. It encourages collagen production, helps to brighten dark spots and pigmentation, and works as an antioxidant to protect the skin against free radicals (unstable molecules that cause oxidative stress on skin cells, AKA premature ageing).

    Not only that, but it’s also a great anti-inflammatory agent, softens rough skin texture and gives your skin one hell of a natural glow (meaning the best face serums containing vitamin C will allow you to skip out on even the very best highlighter).

    How to use vitamin C in your skincare routine

    Now let’s get down to the good stuff: how do you go about starting to use this ingredient in your skin regimen? ‘You have to pay a lot of attention to the form and the concentration you use on the skin,’ says consultant dermatologist and Mohs Micrographic Surgeon at the St Johns Institute of Dermatology Dr Emma Craythorne. ‘The optimal concentration depends on its formulation.

    ‘In most cases, for a product to be of biological significance, it needs to have a concentration higher than 8%. Studies have shown that a concentration above 20% does not increase its biological significance, but might cause irritation.

    ‘Reputable products of vitamin C available today are, therefore, in the range of 10 to 20%,’ she continues. ‘Pure vitamin C is also known as L-ascorbic acid. This is the most effective form of vitamin C on the skin.’

    In short, vitamin C is a fairly punchy active ingredient, so it’s a good idea to let your skin get used to it. But don’t panic – simply introduce it slowly by applying it every couple of days to start with and your skin should adjust. You can then gradually up your usage.

    However, vitamin C is notoriously unstable, meaning that its efficacy and strength is affected by factors like light, air and heat exposure. It’s also a bit of a lone wolf and doesn’t always play nicely with certain other active ingredients. We don’t recommend you apply an AHA or BHA toner beforehand (something with salicylic acid or glycolic acid in it) because it could destabilise the pH level of the vitamin C and stop it from working.

    Ready to find your new hero serum? Below you’ll find our beauty editor-approved round-up of the best vitamin C serums that the market has to offer.

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