Why do I get dandruff in winter?
Last updated September 3, 2026.
Because winter stacks the deck: most dandruff is mild seborrheic dermatitis - yeast-driven - and Mayo notes flares track season change; cold dry air plus indoor heating dehydrates the scalp into shedding more visible flakes. The fix is medicating smarter, not washing less (buildup feeds the yeast): AAD-backed actives - ketoconazole 1%, zinc pyrithione, selenium sulfide, salicylic acid - left on a few minutes, rotated if one stalls. Pymander's escalation routing is built and tested specifically for this class of decision; see the safety architecture working paper.
What to do
- Use a real active: ketoconazole, zinc pyrithione, selenium sulfide, or salicylic acid - 3 to 5 minutes of contact time.
- Do not under-wash: oil and skin-cell buildup is yeast food.
- Cool the shower: scalding water strips the scalp's remaining protection in dry months.
- Get seen if: a month of proper medicated shampoo changes nothing, or redness and thick scale spread - psoriasis and true seborrheic dermatitis need prescriptions.
Related questions
- Why is my scalp so flaky?
- How to treat dandruff?
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