1. What is L-Ascorbic Acid? L-Ascorbic acid is most commonly known as Vitamin C.It is a water soluble vitamin that is essential for growth and repair for many parts of the body.L-Ascorbic acid is an important component for the synthesis of collagen.It is also essential in wound healing and the maintenance of cartilage, bone, and teeth.L-Ascorbic acid is classified as an antioxidant.Antioxidants are molecules that can neutralize free radicals.Free radicals are atoms with odd numbered pairs of electrons and can be formed when oxygen interacts with certain molecules.This occurs during basic metabolism of food and cellular respiration.This chain reaction of destruction can cause major damage to the cell membrane and can also damage DNA.This is one of the major factors that contribute to aging.This micronutrient cannot be manufactured in the body and must be supplemented through outside sources.Vitamin C deficiency can cause gingivitis, rough and scaling skins, and decreased ability to ward off infections.Severe deficiency of L-ascorbic Acid can lead to scurvy. 2.L-Ascorbic Acid and its uses in Sun Protection. - As mentioned before Vitamin C especially applied topically can protect skin against the damaging effects of the sun and free radicals, which become highly reactive when exposed to sunlight.L-Ascorbic Acid is an antioxidant.Thus, L-Ascorbic Acid functions in UV immunosuppression.This is attributed to its ability to neutralize free radicals. Free radicals often permeate the skin cell’s membrane and can lead to inflammation, fine lines, and wrinkles.Sunscreens can also be used to combat the problem, but can often be ineffective because it can be rubbed off or perspired from the skin.Also many people do not apply sunscreen correctly or in inadequate amounts.This is why other sources are important to our skin’s health.L-Ascorbic acid is not meant to replace sunscreens, but used to supplement it and to amplify its benefits. 3. Vitamin C and its Function in Collagen Synthesis. -Vitamin C is the only antioxidant that has been proven to increase collagen synthesis.Collagen is the connective tissue that gives our skin elasticity, suppleness, and structure.Many studies have shown that collagen deteriorates with aging and photo-aging or aging caused by the sun accelerates that decrease.The mechanism of function of L-ascorbic acid in collagen is that it serves to relay signals and critical messages to the genes that activate collagen synthesis.L-Ascorbic Acid also acts as enzyme cofactors that are important to collagen synthesis. 4. Effective versus Ineffective Vitamin C preparations. -There are many derivatives of L-ascorbic acid, many of which are in topical skin products.Research has shown that only the L-form of L-Ascorbic Acid can be absorbed and utilized by our skin’s cells.If other derivatives are used then the body needs to convert them to the L-form. Studies have shown that derivatives are either not absorbed into the skin or are not converted to concentrations that are high enough to affect and become beneficial to the skin. Thus when evaluating a Vitamin C product, ask these critical questions: ● Does the product contain Vitamin C in the L-Ascorbic Acid form? 　-Since this is the only form that can be absorbed by the body, 　make sure to check the ingredients carefully to see if it contains 　that form.It may also be listed as L-Ascorbic Acid. ● Where is the ingredient listed in the ingredient list? 　-Ingredients are listed in decreasing order, which means the first 　 　ingredient listed in the list contains the most and the last ingredient 　listed contains the least. Make sure there is a high enough 　concentration.Research has shown that a concentration higher than 　15% makes a good product. ● Is the preparation stable? 　-Stability of serums can be evaluated in a couple of ways.One is to 　look at the color.If there are changes in color, that can be a sign of 　deterioration.If the consistency becomes watery over time, that can 　also be a sign of a solution that is no longer stable.