Diagnosis Dandruff: Symptoms associated with an imbalance of the scalp - redness, dandruff, irritation, itching, seborrheic dermatitis, signaling a disturbed balance and unhealthy microflora of the head. Dandruff is a very common scalp problem and is caused by a microorganism (fungus) called Malassezia globosa that feeds on the natural lipids or oils produced by your scalp. About Your Hair's professional therapy is focused on fighting dandruff, eliminating the causative bacteria and long-term restoration of a balanced and healthy scalp microbiota.