Hair Loss - Causes

Heredity is known to be the cause in most of the hair loss cases. Dihydrotestosterone — the male sex hormone — is the primary trigger in case of male- and female-pattern baldness.

• Poor nutrition: This is one of the most common reasons for hair loss, especially in India. Iron deficiency (anaemia) tops the list and is followed by protein deficiency. Improper absorption of nutrients can also lead to poor nutrition.
• Crash dieting: Excessive dieting, especially mono dieting, which involves completely avoiding a particular type of food group, disturbs the balance of protein, carbohydrates and fat, leading to hair loss. Sometimes, hair loss does not reverse, even after the patient gets back on a normal diet.
• Oral contraceptives: Certain oral contraceptives using synthetic progesterone can lead to female-pattern baldness. Then again, stopping oral contraceptives is also known to be associated with generalised hair loss for some time.
• Poor circulation: A study of young men diagnosed with male-pattern baldness showed that the blood flow to their scalps was on average 2.6 times lower than in a control group. Follicles that are constantly deprived of blood (and therefore nutrients) cannot produce hair properly.
• Smoking: Nicotine (tobacco) negatively influences the micro-circulation of the scalp, leading to increased hair loss.
• Mental stress: There can be an increased hair loss when an individual is highly stressed, though the exact mechanism of this is not known.
• Dandruff: Dandruff is inflamed, flaky skin on the scalp, which hinders proper circulation and nutrition to the hair, thereby causing increased hair loss.
• Medications: Drugs used in the treatment of gout, depression, arthritis, high blood pressure and heart problems can lead to increased hair loss. Chemotherapy drugs and radiation treatment are other common causes.
• Presence of systemic illnesses: Diabetes, lupus, scleroderma, etc., can cause hair loss. 
• Hormonal changes: Pregnancy, childbirth, menopause, hypothyroidism, hyperthyroidism, etc., can all lead to significant hair loss.
• Hair treatments: Chemical treatment of hair, especially with ammonia-based products, perming, straightening, ironing, etc., can lead to damage and hair loss.
• Infection of the scalp: Scalp infections, especially ringworm, can lead to hair-loss problems.
• Local diseases: Scalp diseases such as psoriasis, lichen planus, etc., can cause hair loss.
• Recuperating from serious illness: Illnesses such as high fever, sudden or excessive weight loss or even post-surgery conditions and metabolic disturbances can lead to significant hair loss.