Applying vitamin C serum: Before or after moisturiser?

When and how to use your serum.

Written by
Sophie Overett
Medically reviewed by
min read
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Vitamin C might just be one of the few vitamins where some of the health benefits are widely known.

From preventing scurvy on the high seas to helping fight colds and the flu, vitamin C is a vital immune system booster and likely something you’ve taken orally at some point in your life.

Lesser known though is that vitamin C can also be a crucial resource for your skin, helping fight environmental damage from the sun and air pollution, and playing an active role in collagen synthesis, keeping you looking fresh and your skin protected.

But how does it work? And how do you know when to apply vitamin C serum without irritating your skin? To answer those questions, let’s first look at what vitamin C actually is.

What is vitamin C?

A powerful antioxidant, vitamin C plays a crucial role in your body’s functioning.

Among other things, it’s responsible for collagen production and strengthening your skin, blood vessels and bones, as well as for helping your body absorb iron, healing wounds and bolstering your immune system to fight infection — all things that are essential to daily life [1].

It also fights harmful toxins, otherwise known as free radicals, that come into contact with your skin from external sources like air pollution, or from inside your body as a result of normal processes like your metabolism, making it important in maintaining healthy skin [2].

Our bodies don’t naturally produce vitamin C, meaning we have to consume it through food, drinks, supplements such as an oral vitamin, or topical products for skin like a vitamin C serum or cream [1].

L-ascorbic acid and vitamin C: Is it the same?

Put simply, L-ascorbic acid is the most refined form of Vitamin C — also referred to as pure vitamin C.

There are other forms of this vitamin C, including ascorbyl palmitate and tetrahexyldecyl ascorbate, but L-ascorbic acid is the most potent (and likely, the most widely-known) one.

What does vitamin C do for your skin?

As it boosts collagen production and protects your skin from harmful toxins, vitamin C has numerous benefits for keeping you and your skin healthy.

Here's the lowdown on how vitamin C serums can boost your skin health:

It can reduce the appearance of fine lines and wrinkles

Good news! While fine lines and wrinkles can be the bane of an ageing person's existence, vitamin C serum could save the day.

Antioxidants, especially when used topically‚ can help your body produce collagen, which is a protein that gives your skin a firmer, bouncier feel.

Collagen production helps to improve the appearance of fine lines or wrinkles, leaving skin looking more youthful.

It can help brighten your skin

If a vitamin C serum is used regularly, it can help even out your skin tone.

Putting a stop to excessive melanin production (the substance that causes pigmentation in your hair, eyes and skin), vitamin C serums are an amazing product to have up your sleeve if you suffer from skin discolouration or an uneven skin tone.

It can protect your skin

As we mentioned above, vitamin C works to protect your skin from unwanted environmental aggressors like the sun and air pollution. It also boasts healing effects thanks to its anti-inflammatory properties, boosting wound healing by helping cells migrate to the area of injury [3].

Its sun protection qualities are particularly powerful when used in combination with a broad-spectrum sunscreen like Software's Daily Sun Defence SPF50+ [2]. It’s also been known to help with acne, but we’ll talk more about that later. What can't vitamin C do?

What are the benefits of vitamin C serums?

Vitamin C serums are a potent antioxidant as they contain active vitamin C, and clinical trials are optimistic about the benefits they have when it comes to protecting your skin from environmental aggressors such as UV rays, pollution and smoking [4].

Being a known replenisher of vitamin E, which protects cell membranes against oxidative stress and maintains the collagen network in the skin, vitamin C serum benefits you by focusing absorption on a particular area of the body and utilising the anti-ageing and anti-pigmentary effect [4].

Who should use vitamin C serum?

While vitamin C serums can generally be used by anyone, make sure you avoid the product if you have sensitive skin or encounter an allergic reaction or redness from any vitamin C products.

In general, folks who experience issues with skin discolouration, wrinkles or dull skin would benefit from using vitamin C products in their everyday skincare routine.

Is vitamin C good for acne-prone skin?

Many studies are showing that it is. Vitamin C has natural anti-inflammatory properties that help to reduce the swelling, skin irritation and discolouration that comes with acne.

It also has been found to help control oil (sebum) production in the skin, which can have a direct impact on breakouts [2].

Potential side effects and risks of vitamin C serums

While most people have no trouble with using vitamin C products, there are a few side effects that you should keep a look out for. For most people, experiencing a side effect of a vitamin C product involves mild skin irritation like tingling upon application.

However, it can also cause more severe effects like redness and itching, mostly occurring in people who have sensitive or reactive skin.

To make sure this isn't an issue for you, patch test the product by applying a small dollop to your inner arm for 1-2 days to see how your skin reacts before integrating it into your skincare routine.

For those with dry or extra sensitive skin, products like vitamin C serums can often have a low pH which is well-known for irritation.

If you have sensitive skin, try using a gentler formula of vitamin C serum at first, preferably one that contains under 5% vitamin C.

Generally, most people with sensitive skin can boost their use by up to 10% or even 20%.

How long does vitamin C serum take to work?

While every situation is different, most people see results from using a vitamin C serum within 3 months [2]

Whether you're noticing a brighter complexion, plumper skin or improvements in hyperpigmentation, vitamin C can work wonders quite quickly!

Choosing the right vitamin C serum

With so many brands out there though, how do you find which topical vitamin C treatment is right for you?

Working with a dermatologist or a verified online retailer like Software is always recommended, particularly if you have sensitive skin.

On top of that, looking for a clinical formulation that contains an active form of vitamin C, such as L-ascorbic acid, has a vitamin C strength of 10-20%, and a pH lower than 3.5 is highly recommended, as this is the recipe that has had the best results in clinical trials [2].

Software’s Vitamin C + Ferulic Acid Serum has all of this and more.

Supercharged with ferulic acid and containing a full 15% dose of vitamin C, this serum is one of the most potent available out there and it is specifically designed to protect your skin cells, brighten your skin and fight atmospheric ageing.

How to store vitamin C serums correctly

As vitamin C serum is designed to protect your skin against oxidative stress, preventing it from oxidising is crucial.

Keeping it sealed and stored in a cool, dark, dry place and avoiding sunlight is the best way to do this. If you’re in a warmer climate, keeping it in the fridge can be a good idea.

Should you use vitamin C serum in the morning or at night?

While you can work your vitamin C serum into either your morning or evening skincare routine, most dermatologists recommend the morning [2].

This keeps your skin protected from free radicals as you go about your day, and can work especially well with your sunscreen to keep you safe from UV radiation.

Should you use vitamin C serum before or after moisturiser and sunscreen?

Dermatologists recommend you apply vitamin C serum before you apply moisturiser and sunscreen. The steps for application are [2]:

  • Use a gentle cleanser to remove any makeup or free radicals from your skin
  • Apply a few drops of vitamin C serum to your face and neck, and gently rub it in
  • Apply moisturiser and sunscreen

Can you use vitamin C and hyaluronic acid together?

You can!

In fact, vitamin C serums work well with hyaluronic acid in promoting skin health.

Both fight ageing and sun damage in ways that complement each other, with vitamin C products promoting tissue growth, collagen production and healing, while hyaluronic acid encourages the skin to retain moisture, keeping your skin hydrated regardless of your skin type [5].

Consider adding a hyaluronic serum, like our Hyaluronic Complex Serum, into your skincare routine. It is designed to instantly hydrate, thanks to the addition of 4 types of hyaluronic acid which help combat dryness and dehydration.

Natural Moisturising Factors (NMF) and sodium hyaluronate crosspolymer attract water from the atmosphere to maintain hydration all day and help keep external stressors at bay by strengthening the skin's surface.

How to use vitamin C serum and retinol

Vitamin C serum works well on its own, but it can be well-complimented by other topical serums, such as retinol, to round out your skincare routine.

With vitamin C serum being ideally used in your morning routine to keep your skin protected during the day from sun exposure and other environmental aggressors, retinol is a restorative skincare treatment that promotes skin cell turnover, and when used topically, deepens skin penetration compared to other treatments, making it a great addition to your evening skincare routine [6].

Layering these topical serums can cause skin irritation and redness though, especially if you have sensitive skin, so make sure you use them separately and patch-test them first.

How to use vitamin C serum and niacinamide

Niacinamide is another ingredient that, when combined with vitamin C, can deliver some serious skin benefits. You just need to know how to apply them correctly as a combination.

For the best results, dermatologists recommend applying your vitamin C serum first. Let it dry so your skin has the opportunity to absorb the ascorbic acid, and then move on to the niacinamide product.

Just like with the vitamin C serum and retinol pairing, be sure to patch test before you start using vitamin C and niacinamide regularly in your skincare regime.

What ingredients should you avoid when using vitamin C serum?

There are a few ingredients to avoid when using vitamin C in serum form.

In particular, it should never be used with any acids, particularly alpha hydroxy acids (also known as AHAs) and beta hydroxy acids (BHAs).

These are most frequently found in exfoliants, so remember to double-check what ingredients your scrubs include before you apply vitamin C serum.

Benzoyl peroxide is another one to avoid if you're using a vitamin C serum as it oxidises vitamin C and therefore cancels out any benefits.

Benzoyl peroxide is mostly found in acne treatments or blemish creams, so again, check your products' labels before introducing vitamin C serum to your skincare routine.

As with any skin treatment, you should start with a patch test to ensure the treatment is right for your skin. If you're creating a sensitive or combination skincare routine, for example, may find vitamin C serums aren't quite right for you.

If you experience any irritation or allergic reaction, you should stop using the serum immediately, and if you have ongoing concerns about vitamin C products or your skin health, be sure to speak to a medical professional immediately.

Can you use vitamin C serums while pregnant?

Vitamin C is not only safe for pregnant women to use, but it's also an incredibly potent addition to your skincare routine.

The environmental and hormonal factors that affect your body during pregnancy benefit greatly from topical vitamin C.

If you're ready to dip your toe into the wonderful world of vitamin C serums, Software's Vitamin C + Ferulic Serum is a hardworking addition to your skincare routine and one that you'll start reaping the benefits from straight away.

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