[Photoprotection and cutaneous carcinogenesis under the Yin and Yang symbols]

The protective effect of sunscreens against cutaneous carcinogenesis was a well established axiom. During the past decade, the reverse opinion was expressed. Unfortunately it led to a sophism proclaiming that topical photoprotection is harmful. The controversy in rife although the best modern sunscreens actually fulfill most of the requirements of molecular photobiology.