VITAMIN C: 101
Since the concept of active skincare began to gain popularity in the late 90s, the ingredient that has remained a firm staple to this day is Vitamin C. A real master of all, Vitamin C is an antioxidant, collagen stimulator, pigment reducer and altogether good guy when it comes to the skin. Vitamin C is abundant in healthy foods and is found in any serum worth its salt, but what actually is this molecule and why does it deserve respect?
WHAT IS VITAMIN C?
Vitamin C or ascorbic acid (or ascorbate) is an essential micronutrient, meaning that we need to take it in via our diet as our bodies don't make it ourselves. Ascorbic acid is a water soluble vitamin that has a number of important functions in the body as a whole and in the skin of course. Acting as a co-factor in many important biological pathways, including collagen formation and wound healing, as well as neutralising damaging oxidative free-radicals on the body via its action as an antioxidant. Lack of vitamin C in the diet can result in a condition known as Scurvy, which is associated with poor collagen synthesis and poor wound healing, as well as the loss of teeth.
In nature, Vitamin C is found in two forms: L-ascorbic acid and D-ascorbic acid, which are basically the same chemicals but with slightly different shapes. L-ascorbic acid is a fairly unstable molecule and can be broken down or denatured by UV light and even air. When it does this, it can form a brownish coloured compound known as dehydroascorbic acid (DHAA), which then breaks down into molecules that can irritate the skin.
A more stable form of Vitamin C can be created when a metal ion is added to the ascorbic acid, creating a ‘mineral ascorbate’ or ester. These are commonly found in skincare and the vitamin C molecule is attached to metal molecules (ions) such as calcium, magnesium, sodium and phosphorus. These are generally water soluble and much more stable than L-ascorbic acid.
WHERE CAN I FIND VITAMIN C IN NATURE?
Vitamin C is hugely abundant in nature. Found mostly in fruits and vegetables, we should all be getting plenty if we have a healthy and balanced diet. Rich sources include citrus fruits, berries, sea buckthorn, peppers and many others. One of the highest concentrations is found in the Kakadu plum, a fruit native to Australia, which contains over 2300mg/100g (which is huge when compared to oranges (50mg/100g))!
WHAT ARE THE BENEFITS OF VITAMIN C ON THE SKIN?The skin is exposed to many damaging factors including UV light from the sun, pollution and irritants on a daily basis. These in turn cause irritation, inflammation and the production of oxidative ‘free radicals’, i.e. highly reactive molecules that cause cell and DNA damage in the skin. These free radicals also damage proteins including collagen and elastin. Vitamin C first and foremost functions as a scavenger or neutraliser of these free radicals. In this way, it helps reduce damage to the skin cells.
Vitamin C also has effects on the skin DNA itself, acting as a co-factor in many reactions that promote the production of collagen and elastin, and also aids the skin’s natural healing processes. It can also reduce the production of excess melanin pigment and reverse some of the changes associated with old sun damage such as pigmentation.
Not only is vitamin C good for reversing some of the changes associated with sun damage, but there is also some scientific evidence that, in combination with vitamin E, it can also protect against UV and may even prevent future damage to the skin.
WHAT ARE THE FORMS OF VITAMIN C FOUND IN SKINCARE?From a skincare point of view, there are a number of factors to consider when choosing the type of vitamin C to use. Formulations containing L-ascorbic acid can be quite difficult - not only are they unstable and break down (oxidise) when they are exposed to the air or sunlight, but they are only able to penetrate deeper into the skin in very acidic environments (around pH 3.5 or below), which can be quite irritating for the skin. For this form of vitamin C to be effective, it can only really be used safely under the supervision of a specialist. In addition, L-ascorbic acid needs to be stored in the dark to prevent breakdown by light!
As a result, in home skincare, the most commonly found forms are the water soluble vitamin C esters. These include ingredients such as:
- Sodium ascorbyl phosphate [link to good morning]
- Sodium ascorbate
- Magnesium ascorbyl phosphate and magnesium ascorbic palmitate
- Ascorbyl palmitate [link to good morning]
- Calcium ascorbate
All of these will come in a base that includes water (might say aqua) on the inci list on the back of your product, rather than an oil base. The benefits of these are that they are much more stable, they don't tend to oxidise in light or air so are easy to store, and are much less pH-dependent so can be used at higher pHs that are less irritating to the skin. Usually, these forms of vitamin C are white or clear and won't oxidise quickly when you put them on the skin.
SO WHAT IS THE BEST FORM AND WHAT SHOULD I BE USING?
Although there are many different forms of vitamin C available, in skincare usually a stabilised vitamin C ester is the easiest, least irritating and most straightforward form to use. Ester forms of vitamin C are slightly less effective than the L-ascorbic acid form, however, even at very low percentages (even as low as 0.6%) still have anti-ageing benefits on the skin. Currently, the thinking is that ascorbyl palmitate is one of the better forms to use. The reason for this is that the palmitate bit on the molecule (i.e. palmitic acid) makes it fat soluble, which allows it to penetrate get through the protective lipid (fat) layer on the surface of the skin so it can penetrate deeper into the layers of the skin. For this reason, we use two forms of Vitamin C in our Good Morning! serum: sodium ascorbic phosphate and ascorbyl palmitate.
Usually, the optimum recommended skin concentrations, to balance effectiveness against the risk of irritation are between 5-15%.
VITAMIN C & E COMBOS
Vitamin C & E are like best friends - good apart but even better together. Vitamin E, a fat soluble vitamin, has good antioxidant and anti-inflammatory effects, as well as promoting wound healing. Together with vitamin C, these two vitamins have a synergistic effect, meaning that their effects together are even better than part i.e. they boost the activity of one another. Indeed, there is a lot of scientific evidence https://www.ncbi.nlm.nih.gov/pubmed/18045356 to suggest that together they can significantly improve protection against harmful UV rays even better together than individually, as well as help treat the effects of sun damage on the skin.
WHAT ABOUT SUPPLEMENTS?
The inside out philosophy for skin health well and truly applies to vitamin C above any other ingredient. There is increasing evidence that a good intake of vitamin C can have an anti-ageing effect via its antioxidant effects internally and also through increased collagen production, in fact, most skincare supplements (including collagen supplements) have vitamin C as their primary active ingredient. We’ve included vitamin C rich ingredients, as well as supplementary vitamin C in all of our skin supplements (SkinShake, SkInfusion, Skin+Hair+Nails) as well as our overnight repair supplement Sweet Dreams for this very purpose!
Vitamin C should be your go-to ingredient for anti-ageing skincare. We recommend using both topically and orally for the best outcome. In skincare, a stabilised form of vitamin C such as sodium ascorbyl phosphate or ascorbic palmitate are our top choices for ease of use and to minimise irritation, and we would always recommend pairing this up with vitamin E (tocopherol).