Dandruff is a mild form of seborrheic dermatitis, and is characterized by a flaky, itchy scalp.[1][2] Dandruff is common, affecting about 50% of the adult population worldwide, and is not caused by poor hygiene.[3] It tends to start during puberty and occurs more frequently in males.[4]
What is dandruff?
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•Last Updated: May 16, 2025
Dandruff is a mild form of seborrheic dermatitis that is characterized by a flaky, itchy scalp; it affects approximately 50% of adults worldwide. It commonly begins during puberty and is more prevalent in men and boys, with no link to poor hygiene.