Dandruff affects roughly one person in two at some point in their life. It is caused by a fungus naturally present on the scalp, Malassezia, which proliferates when the skin balance is broken. The right treatment depends on the type of dandruff. Getting the category wrong means making the problem worse.
How to tell dry dandruff from oily dandruff
Dry dandruff is fine, white, barely adherent. It falls onto your shoulders as soon as you brush or move your head. The scalp is often tight, dry, sometimes prone to mild itching.
Oily dandruff is larger, yellowish, and sticks to the scalp or to the base of the hair. It often comes with an oily scalp, sometimes red, and with more pronounced itching. It is the most common form when seborrheic dermatitis is involved.
The causes, by type
Dry dandruff:
- Dry air (heating in winter, air conditioning).
- Shampoos that strip too much, or are used too often.
- Hard water.
- Stress.
Oily dandruff:
- Excess sebum.
- Hormonal shifts.
- An unbalanced diet (sugar, saturated fats).
- A predisposition to seborrheic dermatitis.
The right habits for dry dandruff
- Space out your shampoos (move to 2 or 3 times a week).
- Use a gentle, sulfate-free shampoo at scalp pH.
- Apply an oil bath (jojoba, argan) to the scalp once a week, left on for 30 minutes before shampooing.
- Rinse with lukewarm water, never hot.
The right habits for oily dandruff
- Favor a purifying shampoo, with clay or with birch, nettle, or rosemary extracts.
- Do not over-wash: 3 times a week at most.
- Absolutely avoid oily styling products near the roots.
- Cut back on sugar and saturated fats during the acute phase.
When to move to a medicated anti-dandruff shampoo
If after 4 to 6 weeks of adjusting your routine the dandruff persists, or comes with redness and patches, a shampoo based on zinc pyrithione, ciclopirox olamine, or ketoconazole (from a pharmacy) may be necessary, generally twice a week for 4 weeks.
What to avoid
Never scratch. Micro-lesions encourage the fungus to proliferate. Do not use undiluted essential oils (often irritating), baking soda, or concentrated cider vinegar: these natural tricks unbalance the pH and usually make things worse.
To identify your type of dandruff and the routine that suits it, take our hair diagnosis, 2 minutes.