The use of vitamin C orally for skin beauty requires high doses, because to get to the skin of vitamin C must pass through a variety of other organs, such as stomach, intestine, and blood vessels. Body's normal requirement of vitamin C is actually only 50 mg per day. However, to obtain the effects of skin care, needed vitamin C at a dose of 20x fold which is about 1000 mg, which was made of vitamin C in the form of solutions that can be directly applied to the skin. But the difficulty is the nature of a solution of vitamin C that is not stable. When exposed to air, a solution of vitamin C will oxidize and lose its effectiveness. Even vitamin C that has been oxidized is dangerous because it can form free radicals.
Various studies have been conducted to obtain a solution of vitamin C are more stable. But the price of this product to be very expensive, especially containing a concentration sufficient to obtain the desired effect. This product is still experiencing oxidation during use, though it takes a longer time.
One option to obtain a stable solution of vitamin C, is the use of vitamin C in the form of serum. Vitamin C is used is in the form of derivatives (derivative). Derivatives of vitamin C is more easily absorbed by the skin and release of ascorbic acid for the synthesis of collagen. In addition to more stable, derivative of vitamin C is not too irritating than vitamin C. At present there are 2 forms of vitamin C derivatives that circulate in the market that is askorbil askorbil palmitic and phosphate.
Askorbil palmitate is a derivative of vitamin C are soluble in fat. This substance has many advantages compared to vitamin C such as not irritating, more stable, and has antioxidant properties which is equivalent to vitamin E to protect skin from lipid peroxidation (skin damage caused by free radicals). Unfortunately askorbil palmitate in skin care products are not as good as vitamin C to help the synthesis of collagen.
Askorbil phosphate is a derivative of vitamin C are water soluble. This substance is also not too irritating and more stable than vitamin C. His ability to stimulate collagen synthesis of vitamin C equivalent but with lower concentrations. So askorbil phosphate is a good choice than vitamin C for people with sensitive skin and avoid the effects of exfoliation (vitamin C is very acidic, causing peeling effect).
Nowadays many skin care products that contain askorbil phosphate, but most products that contain these ingredients have concentrations that are less effective to stimulate collagen synthesis. Although more stable, this substance is still gradually degrades when exposed to air.
So, if you want the effect to stimulate collagen synthesis and exfoliate the skin (rejuvenation), vitamin C can use pure. But if you want a stronger effect to stimulate collagen synthesis, but did not want the effects of exfoliation, can be used derivatives of vitamin C. Consult with your doctor, and adjust to the needs of your skin.