Dandruff is caused by a combination of factors mostly related to the health and condition of your scalp. The main reasons include a dry scalp, excess oil production, fungal overgrowth (especially a yeast called Malassezia), sensitivity or reaction to hair care products, and sometimes other skin conditions like eczema or psoriasis. Specifically:
- Malassezia yeast feeds on oils on your scalp, leading to irritation and excess skin cell growth that flakes off as dandruff.
- Both not shampooing enough or shampooing too frequently can worsen dandruff by either allowing buildup or drying out the scalp.
- Irritation from certain hair products or environmental factors like cold weather and stress can contribute.
- Seborrheic dermatitis, a common oily scalp condition, is often linked to dandruff.
- Individual susceptibility, including genetic factors and hormone levels, also plays a role.
Dandruff is not caused by poor hygiene and is very common, affecting about half of adults worldwide.
