Dandruff and Seborrheic Dermatitis: A Yeast-and-Sebum Problem, Not a Dry Scalp

Summary

Dandruff and seborrheic dermatitis are not a dry-scalp or a hygiene problem; they are a chronic inflammatory response to *Malassezia* yeast feeding on your scalp's sebum, so the move that actually works is to **control the yeast** with a proven antifungal shampoo (ketoconazole, zinc pyrithione, selenium sulfide, or ciclopirox) used on a maintenance cadence, while resisting the intuitive but counterproductive "my scalp is dry, add oil" response, since oleic-rich oils like olive oil can feed the very lipophilic yeast driving the flaking (coconut oil is the instructive exception — its lauric acid