Vitamin C applied topically has been proven to give you photoprotection by preventing oxidation & inflammation and boosting collagen production. Vitamin C is a very effective topical applied antioxidant, especially when combined with other antioxidants like Vitamin E and Ferulic Acid.
I haven’t found many good quality studies proving topical Vitamin C as a wrinkle treatment, or wrinkle preventative. There are a lot of anecdotal reports, and indirect research that indicate topically applied Vitamin C may improve the appearance of wrinkled skin in some people.
Vitamin C may improve the skin’s texture, soften fine lines and wrinkles, stimulate collagen growth, lighten freckles and dark pigmentation (this function is very much dependent on the concentration of Vitamin C), repair and prevent photo damage and give skin a rosy glow. It may also help in slowing skin aging by reducing free radical damage.
Ascorbic Acid & L-Ascorbic Acid (same thing)
Form of vitamin C that has antioxidant properties, is an anti-inflammatory agent and can improve the appearance of wrinkles, uneven skin tone, and brown spots. Ascorbic acid is difficult to stabilize in formulations. Its acid component can be a skin irritant, so the formulation of the skincare product is important to reduce potential irritation, while ensuring the same benefits.
Ascorbyl dipalmitate is a fat-solubile form of vitamin C. When hydrolized, ascorbyl dipalmitate appears to be as bioavailable as ascorbic acid alone. It is used in some topical preparations because it is more stable than aqueous (water-soluble) forms of vitamin C.
Ascorbyl glucoside has a structure in which the C2-hydroxyl group of L-ascorbic acid is masked with glucose.It has the same functions as L-ascorbic acid: exhibiting high antioxidant activity, acting as a coenzyme for enzymes involved in collagen synthesis (namely prolyl and lysyl hydroxylase), and inhibiting the synthesis of melanin. Ascorbyl glucoside has greater stability than L-ascorbic acid and thereby delivers the effects of vitamin C to the skin for a longer period of time.
The role of vitamin C in promoting collagen synthesis and its antioxidant properties have promoted its use on the skin. Ascorbyl palmitate is an ester formed from ascorbic acid and palmitic acid creating a fat-soluble form of vitamin C. Ascorbyl palmitate is frequently used in topical preparations because it is more stable than some aqueous (water-soluble) forms of vitamin C.
Ascorbyl Tetraisopalmitate is a new and expensive form of Vitamin C:
It’s a vitamin C derivative that actually converts into L-ascorbic acid once it’s penetrated the skin, has a longer shelf life and works at a higher pH than LAA. This ingredient is said to need a pH between 4.0 and 6.0 to work best. Only one line of products currently use this ingredient.
Magnesium Ascorbyl Phosphate
Magnesuim ascorbyl phosphate is a water-soluble derivative of vitamin C. Like vitamin C, it can act as an inhibitor of melanin formation and also plays a role in collagen formation. Unlike vitamin C, it is nonirritating and more stable than vitamin C and is effective in significantly lower concentrations.
Vitamin C layered with copper peptides is not recommended because Vitamin C needs a low pH for the skin to absorb it properly and copper peptides would be neutralized at that low of a pH so most sources will say to use one in the morning and one at night.
Vitamin C in skincare is used as an:
Vitamin C & Niacinamide
Q: Can the two coexist in one product and/or can you layer a Vitamin C product over or under a niacinamide product?
A: If both formulations are chemically stable, it isn’t an issue. The incidents of niacinamide being (essentially) rendered ineffective on the skin in the presence of Vitamin C (L-AA form) were studies done in the 1970s and were with high amounts of L-AA/high acidity.
Pinnell S, Yang H, Omar M, Monteiro-Riviere N, DeBuys H, Walker L, Wang Y, Levine M. Topical L-ascorbic acid: percutaneous absorption studies. Dermatol Surg. 2001;27(2):137-42.
Telang P. Vitamin C in dermatology.. Indian Dermatol Online J. 2013;4(2):143-146.
Farris P. Topical vitamin C: a useful agent for treating photoaging and other dermatologic conditions. Dermatol Surg. 2005;31(7 Pt. 2):814-7; Discussion 818.