I start this post by stating that I am not a chemist, aesthetician or pharmacologist. What I have written below is based on scouring the Internet and using my passable secondary school Chemistry classes to determine what works for my skin and using this as a basis for this post.
What is Vitamin C?
Vitamin C is a water-soluble vitamin that is also a powerful antioxidant. Vitamin C plays a critical role as an antioxidant in neutralising free radicals, which prevents them from harming healthy cells. Additionally Vitamin C is essential for the synthesis of collagen, a key structural protein of the skin. Adding Vitamin C to a culture of skin cells (fibroblasts) dramatically increases the synthesis of collagen. So, when Vitamin C is properly delivered into skin cells, there is a good chance to reduce wrinkles and improve skin texture.
What are the sources of Vitamin C?
Vitamin C is known by several different names, including ascorbic acid, ascorbate, L-ascorbic acid and L-ascorbate. Ascorbic acid and ascorbate fulfill the same roles in your body. The “L” designation is specific to the vitamin’s shape, indicating the natural form of vitamin C.
High levels of Vitamin C can be found in numerous fruits and vegetables including kiwifruits, red and green sweet peppers, oranges, broccoli, strawberries, brussels sprouts and grapefruit.
Ascorbic acid, which is known as L-ascorbic acid due to the vitamin’s shape occurs naturally in the skin and has the most amount of skin related research of any form of Vitamin C. It also generally tends to be the most popularly used version of Vitamin C in skincare products.
The effects of L-ascorbic acid on the skin as a topical treatment are to aid in the creation of firmer skin tone, the reduction in uneven skin tone (such as hyper pigmentation) and defence against external stressors i.e. free radicals. Additionally it is also thought to increase the barrier function of skin to decrease moisture loss, protect from UV radiation, and prevent age spots.
My personal experience supports the research that L-ascorbic aids in correcting pigmentation related issues by fading brown spots and curbing melanin development. I have found it a godsend for my skin.
Types of Vitamin C
L-ascorbic acid is the most popular, most researched and peer-reviewed type of Vitamin C. However, it is notoriously unstable and is required to be at a pH of 3.5 or less in an aqueous (liquid but not water) solution or in dry form to be stable.
Due to the above requirement, L-ascorbic acid can be quite irritating and harsh on the skin. Additionally any Vitamin C product you buy should always be in a light resistant and airtight container.
There are other forms of Vitamin C which also have research demonstrating their stability and efficacy when compared to pure L-ascorbic acid, examples include: sodium ascorbic phosphate, ascorbic palmitate, retinyl ascorbate, tetrahexydecyl ascorbate, magnesium ascorbic phosphate and ascorbic glucoside.
I note that the Sunday Riley Vitamin C CEO moisturiser is provided in a jar, and she states that this is because she is using a new type of Vitamin C, which has been proven to be more stable than L-ascorbic acid; tetrahexyldecyl ascorbate. From my research this is likely to oxidise quite quickly and lose its effectiveness within 3 weeks, so I will not be taking a punt with my money on this!
My personal view based on the research I have read is that though these other forms of Vitamin C may have been researched, the efficacy in regard to my areas of skin concern for me personally has not been proven long enough for me to take a punt with my money.
With my admittedly limited knowledge of pharmacology, chemistry etc., I tend to stick to what I know and the type of Vitamin C (L-ascorbic acid) on which I can find vast amounts of clinical research to enable me to take a view and make a decision as to what I am happy to use on my skin to get the results I want.
My Vitamin C usage is as follows:
I always keep my L-ascorbic acid away from light, air and water as this causes the product to break down quickly and lose its efficacy.
The skin can store up to a maximum of 20% Vitamin C and I have found Vitamin C to be most effective for my skin at a concentration of 12% or more. It is acknowledged that the efficacy of L-ascorbic acid is based on it having a low pH and a higher concentration, which can be irritating and a bit harsh on the skin.
I currently use The Ordinary’s Vitamin C product every other night, it is a water-free and silicone-free formula which enables the provided 23% pure L-Ascorbic Acid to remain completely stable.
I alternate my use of the above with Retinoids, i.e. Mondays, Wednesday and Friday nights I use a Retinoid and Tuesdays, Thursday and Saturdays nights I use a Vitamin C serum.
I hope the above is useful, please ensure you do what is right for your skin. Remember my Skin Quartrinity; Genes, Diet, Exercise and Skincare. I am trying to practice what I preach.
Please see below for my review of the Clinique Fresh Pressed Vitamin C products.