Why does my hair get oily and have dandruff?
Nov 28, 2025
Source: Cainiu Health
Dr. Liu Wenmin
Introduction
In general, oily hair accompanied by dandruff may be caused by improper cleansing, a diet high in greasy or spicy foods, pityriasis simplex, seborrheic dermatitis, or Malassezia infection of the scalp. It is recommended to seek medical attention promptly, identify the underlying cause, and receive appropriate treatment under a doctor's guidance. In daily life, avoid frequent perming and hair dyeing to reduce irritation to the scalp from chemical substances.
Generally, oily hair and dandruff may result from improper cleansing, a greasy or irritating diet, pityriasis simplex, seborrheic dermatitis, or Malassezia infection of the scalp. It is recommended to seek medical advice promptly, identify the underlying cause, and receive appropriate treatment under a doctor's guidance. Detailed analysis is as follows:
1. Improper cleansing: Washing the hair too frequently or not washing it for long periods can disrupt the natural oil balance of the scalp, leading to increased oiliness and dandruff. Choose a mild anti-oil shampoo, wash your hair 2–3 times per week, gently massage the scalp with your fingertips, and avoid scratching with fingernails.
2. Greasy or irritating diet: Long-term consumption of high-fat and high-sugar foods can overstimulate sebaceous glands, increasing scalp oil and dandruff. Adjust your diet by consuming more fresh fruits, vegetables, and whole grains; reduce intake of fried and spicy foods; drink plenty of water to promote metabolism.
3. Pityriasis simplex: Accelerated keratin metabolism on the scalp produces fine, dry flakes, often accompanied by mild itching. Patients may use medications such as selenium sulfide shampoo, ketoconazole shampoo, or pyrithione zinc aerosol as directed by a physician, following instructions for regular scalp cleansing.
4. Seborrheic dermatitis: Abnormal sebaceous gland secretion causes inflammation, resulting in greasy yellowish scales, redness, and itching of the scalp. Patients should use medications such as coal tar shampoo, tacrolimus ointment, or vitamin B6 tablets as prescribed to control sebum production and inflammation.
5. Malassezia infection of the scalp: Excessive fungal growth irritates the scalp, impairing its barrier function and worsening oiliness and dandruff. Patients may use antifungal medications such as bifonazole solution, miconazole clobetasol cream, or fluconazole capsules as directed by a doctor to inhibit fungal proliferation.
In daily life, avoid frequent perming or dyeing of hair to reduce chemical irritation to the scalp. Wear loose, breathable hats to prevent prolonged heat and moisture buildup on the scalp. Maintain a regular sleep schedule, avoid staying up late, and prevent endocrine imbalances that could exacerbate scalp conditions.
