It is thought to be an autoimmune disease that affects the hair.
The T Lymphocytes of the immune system attack the hair follicles which stop the growth of the hair and lead to death of the hair and hair follicle.
There are various causes of Alopecia Areata, including
- Heredity
- Previous history of severe illness like typhoid, malaria, tuberculosis, etc.
- Acute or chronic phases of high fever
- Nutritional deficiencies, especially of vitamins and proteins
- Infections of the scalp
- Emotional stress
- Certain drugs like strong antibiotics and chemotherapeutic medicines
- Hormonal changes especially during pregnancy and also after discontinuing the contraceptive pills
- Certain chemicals, like those used to purify swimming pools feature prominently in causes of Alopecia Areata
- Wear and tear of over-grooming
- Repeated bleaching, perming and dyeing
- Temporary dyes are not as harmful as permanent dyes which can damage the hair shaft.