Sun powder is an oral supplement containing polypodium, a fern extract, and nicotinamide, designed to provide an internal sun shield. It increases the skin's tolerance to UV exposure and reduces the risk of sunburn.
I myself take a product called Sun powder that provides an internal sun shield allows me to be in the sun longer
""Dr. Teo Solomani mentions Sun powder, a supplement he helped formulate, as a means of internal sun protection. He takes it daily to reduce skin cancer risk and prevent sunburn, especially when topical sunscreen reapplication is not feasible."