Why do we use a Vitamin C serum?
Vitamin C is one of the most powerful ingredients for your skin, along with retinoids. Both are known to help in the fight of fine lines, wrinkles, dullness, dark spots and uneven skin tone.
From those who are starting to see the first signs of ageing in their early 20s to more mature skin types with or without the visible effects of sun damage, everyone can benefit from adding a vitamin C serum to their daily skin care routine.
What does it do to the skin?
It’s pretty unique in the fact that it works on so many different fronts!
1. Vitamin C is a powerful antioxidant that protects cells from free radical damage caused by the sun and pollution (for the full story on antioxidants, see my previous article).
2. Vitamin C is also an effective skin-lightening agent: it helps with pigmentation issues and uneven skin tone. This happens through inhibiting tyrosinase, the enzyme that causes the conversion of tyrosine into melanin.
3. It stimulates collagen production which is a major ingredient of the scaffolding network that keeps our skin nicely firm and plump.
What to look out for in Vitamin C?
Not all Vitamin C is equal. Always listen to your skin and choose the right vitamin C for your own skin. Choose one your skin (and your wallet) can handle!
The most powerful form of Vitamin C is L-ascorbic acid as it is the active form. Research has shown that a concentration of 10-20% of L-ascorbic acid with stabilising agents such as ferulic acid and tocopherol will have maximum effects on the skin. However, not everyone can tolerate L-ascorbic acid. The low pH of L-ascorbic acid may be irritating for some. For those with dry or sensitive skin the vitamin C derivatives are more suitable. Vitamin C derivatives such as ascorbyl glucoside (used in the Organic pharmacy stabilised vitamin C serum at a concentration of 15%), ascorbyl tetraisopalmitate, ethyl ascorbic acid, magnesium ascorbyl phosphate and sodium ascorbyl phosphate are more gentle on the skin as they have a more neutral pH (less acidic). The derivatives are converted on the skin to L-ascorbic acid. Another advantage of their more neutral pH is that it is easier to layer with other products. Although it is still recommended to apply Vitamin C in the morning and retinol in the evening, in theory you could apply the Vitamin C derivatives such as ascorbyl glucoside at the same time as your retinol, which is not always the case for the more acidic L-ascorbic acid. A serum has the advantage of being fast absorbing making it perfect for layering with other skin care products. You can use vitamin C in the morning as an antioxidant to protect you from pollution and UV damage and at night to improve collagen and pigmentation. However, a word of caution when it comes to layering: layering of active ingredients comes with an increased risk of irritation and professional guidance is recommended to avoid trouble.
'Stability’ is the biggest issue with vitamin C products. Vitamin C is highly unstable in the presence of light, water and air, which means it goes ‘bad’ quickly. A vitamin C serum can change colour over time which indicates oxidisation. A little bit of discolouration is acceptable, but when it is dark brown, it is unlikely to still be effective at doing its job.
The stabilised vitamin C serum of organic pharmacy with 15% ascorbyl glucoside remains stable 6 months after opening, which means you have to finish it within 6 months. This is an advantage as some products with the more active, but less stable form L-ascorbic acid have to be used within one to two months.
Choose a product that clearly state the percentage and type of Vitamin C used and where the ingredient vitamin C is listed higher up in the ingredients' list. The lower down the list, the less the ingredient is represented in the product. The right concentration of Vitamin C is somewhere between 10 and 20%, depending on added ingredients and which type of vitamin C that is used. Less than 10% is unlikely to be very effective and more than 20% has a higher chance of irritation. 15% might hit the sweet spot!
The best way to apply Vitamin C?
As I mentioned earlier, the best course of action is to use Vitamin C in the morning after cleansing your skin and before putting on your sunscreen. Oh and do not forget your hands, your neck and your décolleté, you would not want them to be the ones that giveaway your true age!
What skin type to use it on?
Vitamin C has an excellent safety profile and suits any skin types. When I am saying all skin types, I really mean all skin types. Young and mature skin. Sun-damaged skin and amazingly preserved skin. Fair skin and dark skin. Dry skin and oily skin. Blemish-prone and sensitive skin. What are you waiting for?
A note for those with sensitive skin who are worried about adding a new product to your routine, the advantage of choosing a vitamin C derivative such as ascorbyl glucoside is that they are less irritating compared to the more potent L-ascorbic acid.
Dr Amélie Seghers