I recently had such a disappointing experience with Skinceuticals Phloretin CF (nothing bad happened, but nothing good came of it either) that the key ingredient, phloretin, remained ever since submerged under my radar. Until, that is, I saw an article in the Journal of Cosmetic Dermatology
by researchers claiming to have demonstrated that phloretin protects from sun damage.
The independent researchers were working alongside a team from L'Oreal and they used an antioxidant cocktail of vitamin C, ferulic acid and phloretin. The protective roles of vitamin C and ferulic acid already have a significant pedigree. However, phloretin, is a new addition to the antioxidant sun protection portfolio.
The reason why that addition is important is that previous studies on plant phenol compounds illustrated that phloretin, which is found in the flesh and skin of apples, is particularly good at getting through the skin barrier. In other words, it is bioavailable when many other antioxidants aren't. Plus, other studies have suggested the presence of phloretin can enhance the uptake of other active ingredients applied to the skin.
The team looked at a number of parameters in order to investigate the efficacy of vitamin C, ferulic acid and phloretin (CFerPhlor), including skin reddening and markers of DNA damage.
According to the study, CFerPhlor provided significant protection against erythema (skin reddening), the production of thymine dimers (the most common DNA damage caused by UV radiation) and the production of p53 (a protein induced when the DNA is damaged by UV radiation). They also brought the levels of MMP-9 (an enzyme that attacks collagen in the skin) down to normal non UV-radiated levels.
Phloretin is good at other things too. And a study in Chemical Research in Toxicology
found that it is extremely efficient at trapping cytotoxic compounds such as methylglyoxal (MGO). In fact, in the test, it trapped 80% of them within 10 minutes. Meanwhile a Dutch research team has pronounced it to be an inhibitor of lipid peroxidation.
The only thing is that I haven't been able to find it in anything other the Skinceuticals Serum, which did nothing for me except dry out my skin.