What Could Be the Cause of Suddenly Losing a Large Patch of Hair?
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Sudden hair loss in large patches is a symptom of alopecia areata, commonly known as "ghost shaving." This phenomenon occurs unexpectedly in localized areas of the scalp, often without any sensation. Many times, patients unknowingly discover a bald patch, and the causes of alopecia areata are complex. They are often related to emotional stress, excessive pressure, mental tension, and autoimmune diseases.
According to relevant ancient records, mental stress is the primary cause of alopecia areata. Clinically, it has also been found that significant emotional changes within a short period can lead to a series of abnormalities in endocrine and glandular secretions, ultimately resulting in alopecia areata.
Abnormalities in the immune system are one of the main causes of alopecia areata. Local phagocytes may mistake hair follicles as abnormal invaders and attack them, causing hair loss within a short period. This type of hair loss usually lasts for about 48 hours and stops after the body adjusts and returns to normal.
Women are prone to alopecia areata after childbirth, mainly due to a decrease in female hormones that cannot provide sufficient growth hormones for hair. However, with time for recovery and adjustment, hair loss usually improves within about six months. Some patients with thyroid diseases may also experience alopecia areata, mainly related to hyperthyroidism.
Some patients with alopecia areata experience habitual hair loss with regional characteristics. When living in a specific environment or location, the incidence of alopecia areata increases, while changing the environment significantly reduces the incidence. This is mainly related to living factors such as water, soil, and diet.