can cause either an overly dry scalp with itchy white flakes that may be waxy or greasy, or it can manifest as an oily scalp with scales.
Internal causes include hormonal imbalance, poor health, poor hygiene, allergic hypersensitivity, lack of rest, emotional stress, excessive consumption of sugar, fat or starch and heredity predisposition.
External
causes include excessive use of hair sprays and gels, improper use of hair-coloring products, cold weather and dry indoor heating, infrequent shampooing of the hair or inadequate rinsing of the scalp and hair. Sometimes it can be due to fungal infections or allergies.
Eat a healthy diet. You can also take vit B6 and vit A and E which are good for hair and skin. Try medicated shampoos for dandruff. There are a number of over-the-counter shampoos available that can help. The most effective ingredients -- antimicrobials -- to look for are zinc pyridinethione, selenium sulfide, sulfur and ketoconazole (also available by prescription). If your hair is colored, don't use products with selenium sulfide or sulfur.
If the symptoms persist please consult a trichologist for the confirmatory diagnosis and treatment.
Hope it helps.Take care and pls do keep me posted on how you are doing or if you have any additional queries.Warm regards.