If your dandruff comes back every time you stop using anti-flake shampoo, you have been treating the wrong problem. Dandruff is a fungal overgrowth, not a hydration issue — and the routine that actually fixes it is the opposite of what most people try.
Dandruff is caused by Malassezia globosa, a yeast that lives on everyone's scalp but overgrows when sebum levels rise. The flakes are dead skin cells shedding fast as the scalp reacts to malassezia's metabolic byproducts. So 'moisturizing' the scalp with heavy oils or rich conditioners actually feeds the yeast — making the problem worse.
The fix has three parts. First, control the food source: a salicylic acid 2% shampoo twice a week regulates sebum and exfoliates dead cells. Second, suppress the yeast: alternate with a ketoconazole 1% or pyrithione zinc 1% shampoo, also twice a week.
Massage in, leave on for three minutes, rinse. Third, restore the microbiome: most days use a mild prebiotic shampoo with inulin or alpha-glucan oligosaccharide that supports beneficial scalp bacteria without stripping. Avoid coconut oil, argan oil masks, and silicone-heavy conditioners on the scalp — all three feed malassezia.
Tea tree oil at 5% is a folk remedy with limited evidence, but it does not harm. Two weeks of this routine clears 80% of cases. Chronic seborrheic dermatitis needs a dermatologist — different prescription antifungals.
The microbiome wants balance, not war.
