Ultra Stable, Lipid Soluble Vitamin C exclusively from Medik8
L-Ascorbic Acid, more commonly known as water-soluble Vitamin C, has many biological functions within the human body. Vitamin C’s most important role is its involvement in the production of connective tissue protein – collagen; adding vitamin C to a culture of skin cells (fibroblasts) dramatically increases the synthesis of collagen.
Vitamin C also functions as an antioxidant and protects cells from free radicals which can lead to oxidative damage (free radicals are formed from external environmental factors such as UV radiation, pollution, cigarette smoke and can even by formed while metabolising certain foods). Vitamin C cannot be stored in the body and is continuously excreted, therefore no matter how much we consume orally, only small amounts reach our skin cells in order to help them to function with the synthesis of collagen or to help fight free radicals.
Most trials show that concentrations of 10% or more ascorbic acid is required topically for anti-aging benefits such as collagen production. Collagen is the most abundant protein in the skin and vitamin C plays a vital role in the maintenance and continual growth of healthy skin. If the appropriate levels of vitamin C can be delivered to the skin topically, then it can contribute and aid in the repair of UV radiation-induced skin damage, prevention of oxidative damage caused by free radicals and can support wound healing by helping the synthesis of collagen. The topical application of vitamin C can also help to prevent premature aging and wrinkling of the skin, as its ability to keep the synthesis of collagen maintained will result in skin which is firm, yet smooth and flexible.
However, there are some downsides to vitamin C in the L-Ascorbic Acid form. It is acidic and may be irritating for people with sensitive skin, especially at the high concentrations required for the synthesis of collagen (10%) and it is highly unstable. Unstable vitamin C is not only worthless in terms of anti-aging benefits, it may actually contribute to the aging process by becoming pro-oxidant when it degrades, increasing the formation of free radicals. In badly prepared or stored products the vitamin C content may already be oxidised by the time you apply it to your skin. Beware of tinted moisturisers containing vitamin C which are often created to prevent consumers from witnessing the tell-tale yellowish tint of oxidising vitamin C. It is worth adding that the colour change occurs some time after the start of oxidation so even white creams can be in the process of oxidation.
There are alternatives to the traditional water-soluble forms of vitamin C, which are more stable and minimise skin irritation. Medik8 have pioneered C-Tetra & CE-Tetra.
Tetrahexyldecyl Ascorbate (C-Tetra) is related to ascorbyl palmitate, but has four times more hydrophobic lipid soluble (fat-loving) palmitic acid molecules, which means that the molecule is more easily able to penetrate the cell membrane. Tetrahexyldecyl Ascorbate is the most powerful synthesiser of collagen of all of the derivatives and is also the most stable, making it the ideal choice for Medik8 products. It is also more stable than vitamin C or any other of its derivatives and is non-irritating. Full studies are available to skin care profesionals in the professional are of the website.
Tetrasubstituted Lipophilic Ascorbates are the holy grail of vitamin C derivatives and C-Tetra (tetrahexyldecyl ascorbate) is the leader in the class. Medik8 offer tetrahexyldecyl ascorbate in a very simple vehicle to ensure the absence of interference from other ingredients that would be in a regular emulsion cream or gel. C-Tetra is a trademark of Medik8 and therefore C-Tetra & CE-Tetra are only available through Medik8.
Interaction with vitamin E
Vitamin E can also be used to help vitamin C to remain stable, as vitamin E behaves as an antioxidant to regenerate vitamin C; and vitamin C to regenerate vitamin E in return.They are called network antioxidants. Vitamin E does not offer much protection of vitamin C from being oxidised in a water solution which is a problem for cream and gel formulae but since Medik8 vitamin C serums are all lipid-based, vitamin E exists in the same phase. Accordingly, C-Tetra with vitamin E benefits from antioxidant protection both in the packaging and on the skin.