Why does tanning via melanogenesis offer limited protection against UVB-induced DNA damage, even as skin darkens?

💡 Explanation

Melanogenesis is a photoprotective mechanism where melanocytes produce melanin that absorbs UV radiation. However, melanin synthesis also generates reactive oxygen species (ROS), which contribute to DNA damage; therefore, its protective effect is limited because ROS counteract the benefit. Rather than complete protection, it is a mitigating factor.

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