Vitamin C Skincare: What’s Important, What Dosage Do You Need, and Why It’s a Skin Routine Essential

Woman in bikini looking happy in the sun
I consider vitamin C to be the great skin ‘fortifier’—a powerful antioxidant able to protect the cells from damage, particularly solar radiation and other environmental aggressors. It is the most plentiful antioxidant in human skin, however humans cannot synthesise this precious active ingredient from scratch so we need to rely solely on nutrition and topical application.

Not all vitamin C ingredients are created equal. Just like vitamin A exists in different forms, so does vitamin C. Dr. Sheldon Pinnell discovered the cellular benefits of vitamin C as an antioxidant in the early 90’s and concluded that all forms of vitamin C must be converted to L-ascorbic acid for the skin cells to use them. 

Now, let’s dive into the epidermis and talk about the key benefits that we can expect from topical vitamin C therapy and then how I go about harnessing these glorious benefits within my products at Synergie. Here are my 6 key benefits of topical vitamin C therapy:


Powerful antioxidant & protects from photoaging

Vitamin C neutralises free radical damage from solar radiation and pollution to protect the cell membrane and DNA from damage. Science-y, right? I like to consider it ‘the fortifier’ as it acts like a protective army around the cells. Free radical damage is largely a result of damage from UV light and, for this reason, it is a great antioxidant to partner with sunscreen.



Vitamin C reduces the activation of cellular molecule transcription nuclear factor kappa ß. This results in reduction of the release of inflammatory factors in cells (called pro inflammatory cytokines). In short, L-ascorbic acid reduces redness and inflammation in the skin, which is the basis of nearly all skin disorders. Can you see why I love it so much?


Stimulates collagen production

Vitamin C is an essential co-factor for collagen production in cells as it directly stimulates collagen synthesis by stabilizing the molecule responsible for its synthesis (procollagen mRNA). It also indirectly promotes collagen production by suppressing the molecule that breaks down collagen in cells (called MMP1).


Helps brighten skin tone

Vitamin C suppresses the formation of skin pigment (melanin) and helps uneven skin tone, making it the perfect tool in the toolbox for those with hyperpigmentation concerns!


Protects against UV-induced immunosuppression

Vitamin C maintains activity of immune cells in the epidermis, the Langerhan cells. These cells are important for protection and are reduced by UV light exposure.


Protects against UV-induced skin cancer

Topical vitamin C reduces UVB damage, sunburn, cell death from UVB damage and UVB induced mutation, which can lead to skin cancer.


When it comes to formulating Synergie Skin products, I refer to my ‘SEED’ principle. For me it’s really a no-brainer, take that ‘SEED’, water it with your chosen form of vitamin C and make it a part of your skin care routine! The benefits are just too good to not let that seedling germinate and thrive! So, let’s consider what you should look for in topical vitamin C therapy:



The ingredient must not be prone to oxidation or breakdown.

The thing with L-ascorbic acid is that it is highly unstable and readily oxidized in the presence of water and heat after just a few hours. The benefits of vitamin C are enhanced by pairing it with stabilising antioxidants such as alpha lipoic acid, ferulic acid, vitamin E and superoxide dismutase. These ingredients help to protect vitamin C from breakdown. Vitamin C serums are notoriously difficult to stabilise in a serum, which is why I prefer to formulate with pure vitamin C crystals. At Synergie Skin, I have formulated vitamin C in two forms:

Pure-C Crystals (L-ascorbic acid crystals) exists as a dry powder which is very stable with added alpha lipoic acid to further fight free radicals and renew the skin. The crystals are kept dry until you add the liquid component at the time of application to their skin. The ideal vitamin C crystal activator is just a few drops of water, mixed at a ratio of 1:4 crystals to water. You can also mix your vitamin C crystals with any of the following aqueous serums at the same 1:4 ratio for a supercharged experience:

HydroGel – for oily, acneic skin
 – for minimising fine lines
EnLighten – for improving uneven skin tone and hyperpigmentation

SupremaC+ (stabilised serum with 3-O-Ethyl Ascorbic acid, the latest of vitamin C). Unlike other vitamin C serums, this derivative is stable and will not oxidise in light, oxygen or heat. This ingredient has an 86.3% conversion to ascorbic acid in the deeper cellular layers, which is the highest of all the vitamin C derivatives, apart from L-ascorbic acid. If you prefer the convenience of a ready-to-use serum, 3-O-Ethyl Ascorbic acid is currently the best option.



The ingredient must actually work and have data to support the benefits and to ensure effectiveness.

L-ascorbic acid

L-ascorbic acid is the only form of vitamin C recognised by the cells and is the only form of vitamin C to be supported by scientifically validated clinical data. There are other forms, like Magnesium ascorbyl phosphate (MAP), but it exhibits low absorption through the skin due to charge on the molecule, and another ingredient, ascorbyl palmitate, is just not as effective on the cells. L-ascorbic acid all the way!

The discovery by Dr. Sheldon Pinnell states that the pH of L-ascorbic acid in water based serums should be less than 3.5 for optimal penetration and deep dermal delivery, and the maximum dose for effectiveness is 20% L-ascorbic acid. Hence the 1:4 ratio! The L-ascorbic acid crystals in Pure-C Crystals are easily absorbed through the skin due to the low molecular weight, which is why I keep coming back to this wonderfully effective ingredient. 

CMF Triacid Complex / 3-O-Ethyl ascorbic acid

We know that L-ascorbic is the gold standard form of vitamin C. However, the latest ingredient, 3-O-Ethyl Ascorbic acid, is a stabilised form that quickly converts to L-ascorbic acid in the skin and therefore offers the elegance of a lightweight serum with the benefits we know and love of L-ascorbic. Tick, tick, tick!

I have taken this new vitamin C derivative to the next level by incorporating it in a trademarked blend of ingredients that work in synergy to rejuvenate and protect. Our vitamin C serum contains 20% CMF Triacid complex™ which is a powerful combination of 3-O-Ethyl Ascorbic acid, Mandelic and Ferulic acids.



The ingredient must have that ‘feel good’ quality so the customer really wants to use it. As well as touch and feel, the product must not have an unpleasant fragrance.

Both Pure-C Crystals and SupremaC+ are considered highly elegant, if I do say so myself. Both are simple to apply (recommended for morning application to combat solar damage) and well tolerated by most skin types. Although some individuals prefer the one-step application of SupremaC+, using one over the other is really just a matter of preference.



The cosmeceutical active ingredients must be able to reach the target cell to create the desired biological effects.

Pure L-ascorbic acid will only be effective if it is delivered to the target skin cells where they can exert their benefits. Pure-C Crystals possess a very small particle size and are easily absorbed through the skin with a water-based solution or stabilised in a non-comedogenic oil.

SupremaC+ is a stabilised form of vitamin C that quickly converts to L-ascorbic acid in the skin, offering the elegance of a lightweight serum. Ethyl ascorbic acid also possesses a low molecular weight and is supported by cutting edge delivery vehicle DMI (dimethyl isosorbide).

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