What can vitamin C do for your skin?

We know that vitamin C comes from oranges, but how do we get from the citrus fruit to a brightening serum?

Vitamin C is a vitamin that became popular in the 1930s when doctors identified the role it had in treating scurvy. For this reason, the chemical name for vitamin C, ascorbic acid, literally means “without scurvy”. An understanding of the benefits of vitamin C in our skin came later.

What can vitamin C do for your skin?

Vitamin C is one of the most researched skincare ingredients out there, and has been scientifically proven to improve the appearance of your skin. It works to:

Shield skin from external aggressors

Vitamin C is what’s known as an antioxidant, which means it shields skin from free radicals. Not up to speed on free radicals? They’re molecules or atoms created by things like UV, pollution and stress which can damage healthy cells. They’re unstable, and buzz around looking for healthy molecules to pair up with. When they pair with a healthy molecule, that becomes a free radical too, and the cycle continues.

Brighten dullness

If skin is continuously exposed to free radicals, it will start to become dull and lacklustre. By protecting skin with an antioxidant, your complexion will stay clear and radiant.

Fade and prevent pigmentation

Age and post-breakout dark spots needn’t be a fact of life. Vitamin C is part of a family of ingredients called tyrosinase inhibitors. They’re effectively blockers, stopping the skin from producing dark marks.

Encourage collagen production

Vitamin C is required for the production of collagen, the protein responsible for plump, bouncy skin. Natural levels of collagen deplete as we age, so it pays to give its production a helping hand.

How can I tell if a vitamin C is any good from the packaging?

To determine whether or not a vitamin C product is worth the investment, there are a number of on-pack cues to consider. They include:

The type of vitamin C it contains

There are a number of different variants of vitamin C, and unfortunately you can’t take a one-size-fits-all approach. Think of it like jeans – there are wide, straight, skinny – all in the same family but all working differently. Not all types will suit everyone, and you will need to shop around to find the right one for you.

Here are some of the most commonly used forms of vitamin C to look out for:

L-Ascorbic acid

This is the most potent form of vitamin C, but also the least stable, meaning it can cause irritation. It does a good job of fading pigmentation but you need to weigh up the pros and cons.

Ascorbyl tetraisopalmitate

An oil-soluble form of vitamin C, it will also help to nourish your complexion. A good choice for dry or dehydrated skin.

Sodium ascorbyl phosphate

If you find that vitamin C can cause you to break out, try this. It has strong acne data and works well with blemish-busting salicylic acid.

Magnesium ascorbyl phosphate

More stable than L-Ascorbic acid, this has proven brightening effects on the skin.

The percentage

Percentages can be difficult for consumers to navigate, as not all brands are transparent about them. This can be for a number of reasons, but in most cases it's to avoid opening themselves up to copycats or potential scrutiny. Products need to contain at least 8% vitamin C to be effective and most of the key players in the skincare market use between 10% and 20%.

The ingredients lists you see on the back of packs order ingredients by percentage, with the highest percentages at the top. In a quality vitamin C serum, you should expect to find vitamin C in the top four ingredients. A good test is to see if it is beneath a commonly used preservative called phenoxyethanol. This can only be used at a maximum of 1%, so if the vitamin C is beneath it, you know the percentage is very low.

What else it’s formulated with

Antioxidants are team players, and their effects are supercharged when combined together. Look out for antioxidants like vitamin E and ferulic acid on the ingredients list, which work especially well with vitamin C. Think of it like lifting a heavy table – the more people there are to help, the easier it will be.

Water soluble vs oil soluble

Most people have a preference when it comes to the texture of their products. Vitamin C products come in two forms, water soluble and oil soluble. As a general rule, water-soluble forms are more lightweight and absorb more easily. They’re a good choice for oilier complexions or those that don’t like the feeling of anything too heavy. Oil-soluble formulas tend to be thicker, and sit for longer on the surface of the skin. Opt for these if your skin is dry or dehydrated.


When it comes to vitamin C, you do get what you pay for. Raw material costs vary wildly depending on which type of vitamin C you’re using. For example, L-Ascorbic acid costs around £18 a kilo, compared to ethylated ascorbic acid which can be up to £700 a kilo.


Vitamin C is a bit of a diva, and exposure to light and air can cause it to oxidise and break down. This is why you might find that your older vitamin C serums have become brown and gloopy, and is a signifier that they’re past their best. To extend the life of your product, vitamin C should always be in opaque, air-tight packaging and kept in a cool, dark place away from heat sources. A dressing table drawer is the perfect spot.

How should I use vitamin C in my routine?

How best to use your vitamin C serum will depend slightly on your biggest concerns. For free-radical protection, it is best worn during the day when skin is under siege from things like pollution and UV. The vitamin C will sacrifice itself in order to shield the skin. If you’re concerned about pigmentation, you might want to double-down and use vitamin C at night, when it doesn’t have other distractions to contend with.

For maximum opportunity to work its magic, vitamin C is best used in leave-on products like serums and moisturisers. It works well with other antioxidants, but less well with alpha and beta hydroxy acids. Also avoid applying vitamin C and retinoids at the same time, as this can cause sensitivity.

How can vitamin C help with hyperpigmentation?

Hyperpigmentation is caused when melanocytes, the cells that produce melanin (the pigment that gives our skin its colour) go into overdrive. Instead of producing a regular amount of melanin, they make far more than is needed, which is why we get dark spots. This can happen when skin is exposed to the sun (age spots) or after a blemish (post-inflammatory hyperpigmentation). Hormone surges and imbalances can cause pigmentation too.

Vitamin C helps to block the overproduction of melanin, helping to prevent new pigmentation from forming. It will also help to fade existing marks too.

Picture it like a carpet. If you spill something on it, if you leave a mark behind, just as UV and breakouts leave marks on the skin. Vitamin C works like a stain-repelling treatment, stopping marks from forming in the first place. If you apply the stain treatment consistently to existing marks, they will also fade with time.

How does vitamin C in cosmetics compare to prescription strength?

The key difference between cosmetic products and prescription strength ones is that the latter are medicine, and can only be prescribed under the care of a doctor. The doctor will take a number of factors into account, such as your age and all round health, to ensure it’s the right treatment for you. Prescription products can be used at higher strengths and in combinations that are not allowed within the skincare market. They are designed to treat or cure a particular condition and will have long term, if not permanent effects.

Cosmetic products (the category skincare slots into) only have a temporary effect. They can offer impressive results, but you’ll need to be consistent. If you stop using them, then the concern you were hoping to tackle, such as pigmentation, will return.

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