There are two types of vitamin C creams on the market: those with acidic vitamin C, called L-ascorbic acid, and those with vitamin C derivatives, ranging from ascorbyl palmitate to magnesium ascorbyl phosphate to ascorbyl glucoside.
Why L-Ascorbic Acid Can Be Better
The advantage of the L-ascorbic acid version is two-fold: one, the concentration necessary to be effective is well-established in numerous scientific journals. Two, L-ascorbic acid is, well, an acid, and an acidic pH has been found to be necessary for vitamin C to penetrate the skin.
Why Perricone Ester C is a Groundbreaking Vitamin C Derivative Product
Many companies will list the concentration of L-ascorbic acid in their products, as with Skinceuticals CE Ferulic. However, no one has ever dared to list the concentration of vitamin C derivative(s) in their product before, which makes Perricone Ester C SPF 15 ($120.00 Amazon.com) truly groundbreaking.
This is the first vitamin C derivative cream I know of to tout an impressive 15% ascorbyl palmitate. Most creams on the market don’t report what concentrations of ascorbyl palmitate are present, and my best estimate is about 1-2% – maximally. A 2001 study in the International Journal of Pharmaceutics found the stability of ascorbyl palmitate is increased when it is present in solutions of at least 1-2% – so the 15% in Perricone Ester C SPF 15 clearly qualifies.
But the pH is wrong…Needs to be acidic
However, again, my qualm about Perricone Ester C SPF 15 is that vitamin C has been found to be most efficacious when it is present at a pH of 3.5 or less (Journal of Biochemistry, 1993). In the study, a low pH was found to be necessary for vitamin C to penetrate the stratum corneum (the uppermost layer of skin).
Derivatives of vitamin C, like ascorbyl palmitate, generally break down in the skin into L-ascorbic acid and some other compound before becoming active. Because Perricone Ester C SPF 15 does not have an acidic pH, it is unlikely that the breakdown to vitamin C will penetrate deep into the skin as with the L-ascorbic acid in Skinceuticals CE Ferulic and other L-ascorbic acid solutions.
So, overall, I admire Perricone Ester C SPF 15 due to the fact that it contains a whopping 15% ascorbyl palmitate. However, given the fact that the product is still non-acidic, and also does not contain any network antioxidants that strengthen the power of vitamin C (i.e., vitamin E and alpha lipoic acid), I will still be sticking to my L-ascorbic acid and Skinceuticals CE Ferulic until further notice. That said, if you’re always on the lookout for something new, Perricone Ester C SPF 15 is likely to give you more skin-brightening, collagen-building results than any other vitamin C derivative product on the market. That, I will attest to firmly.
Product Rating: 9/10
- High or optimized concentration of proven effective ingredients: 3/3
- Unique formulation or new technology: 3/3
- Value: 2/3
- Sunscreen-boosting: 1/1
Ingredients: Water, Ascorbyl Palmitate, Isopropyl Palmitate, Cetearyl Alcohol, Glyceryl Stearate, PEG-100 Stearate, Ceteareth-20, Dimethicone, Phenoxyethanol, Cyclopentasiloxane, Caprylyl Glycol, Cyclohexasiloxane, Fragrance/Parfum, Zinc Sulfate, Disodium EDTA, Limonene, Elaeis Guineensis (Palm) Oil, Tocotrienols, Sorbic Acid, Tocopherol, Sodium Hyaluronate, Linalool, Citral.