Humans have approximately 100,000 scalp hairs, and each hair follows an individual growth cycle. The anagen phase is characterized by active growth and may last for 2 to 8 years. This phase determines the individual hair length. The anagen phase is followed by the catagen phase with growth regression lasting for about 2 weeks. Ultimately, the hair sheds during the telogen phase and rests for 3 months. While shedding 100 to 150 hairs a day is normal, severe thinning, a receding hairline, bald spots, or symptoms like pain or itching of the scalp may be signs of an underlying disorder.
Dermatologists are specialized not only in treating skin diseases, but also in hair and nail disorders. Hair loss is one of the most common complaints. From a dermatologist's perspective, it is important to determine if there is abnormal hair shedding or a reduction in hair density with visible balding, or both. In cases of increased hair shedding, individual triggers such as high a fever, surgery, or a serious illness 3 to 4 months prior to the onset can often be identified. Another example is postpartum hair loss. The medical term for this is called telogen effluvium. It means that more hair than usual enters the shedding (telogen) phase of the hair lifecycle. It can last for six to nine months before it stops. The good news is it returns to normal spontaneously without treatment.
Visible balding should be addressed differently. It may be patchy, diffuse or patterned. There are many possible underlying causes. Scarring alopecia includes all forms in which the hair follicles are permanently lost. Performing a small biopsy may be helpful in establishing the right diagnosis, especially since some forms present with severe inflammation and treatment should rapidly be initiated. In contrast, non-scarring alopecia, such as alopecia areata is potentially reversible.
If you’re noticing that you’re losing hair:
1. Consult a board-certified dermatologist as hair loss can have many causes
2. The frequency in which you wash your hair does not affect hair loss. Most people affected by hair loss reduce the frequency in which they’re washing their hair. However, the same amount of hair sheds in a week whether someone washes it daily or once a week.
3. Limit use of curling irons, flat irons, aggressive hair coloring, and bleaching to avoid additional breaking of hair shafts
4. Avoid pulling the hair too tightly in a bun/ponytail to avoid a type of hair loss called traction alopecia
5. Stop smoking
6. Eat a balanced, plant-focused diet and avoid eating too few calories
7. Only use supplements in the case of a deficiency. While taking a supplement to regrow your hair may seem like an easy solution, getting too much of certain nutrients may worsen hair loss
8. Perform a laboratory test including zinc, thyroid, and iron levels
9. Try to reduce stress as it can cause temporary hair shedding
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