Sunscreens are essential to protect the skin against sunburn. Antioxidants like β-carotene and trans-resveratrol, alone or combined have the potential to limit the delivery of UV filters into the stratum corneum and viable epidermis. 

A study investigated the presence or absence of antioxidants (trans-resveratrol and β-carotene) in formulations containing benzophenone-3 (UV-filter), along with their efficiency under disinfection and neutral conditions. 

It enrolled 38 participants who were subjected to the application of the prepared ointments on the forearms, followed by irradiating and monitoring by reflectance colorimetry at 0, 4, 6, and 8 min. Descriptive statistics and the F-ratio was used for analysis. 

The observations were as follows-

• Antioxidants and benzophenone-3 containing ointment were rendered to be the most efficient, followed by those with benzophenone-3 alone.
• Effective photoprotection with benzophenone-3 was proven, although it leads to the formation of chlorinated products.
• A short time of exposure to disinfecting conditions suggested that benzophenone-3 was probably only partially chlorinated.

Thus the formulations containing antioxidants have greater efficacy for protecting skin against UVB irradiation than a UV filter alone.

Source: Sotler R, Adamič M, Jarni K, Dahmane R, Trebše P, Kralj MB. Analyzing the Photoprotection Efficiency of Sunscreens Containing Antioxidants under Disinfection Conditions. Antioxidants (Basel). 2021 Oct 28;10(11):1720. doi: 10.3390/antiox10111720. PMID: 34829592.