Hair Loss
There are an average of 100 thousand hairs on a healthy scalp in adults. It is considered normal to lose an average of 100-150 hairs per day depending on combing and washing.
The stages of hair are divided into three parts. The growth phase is the longest. Completing this phase. The hair then enters a regression phase (2-3 weeks) that lasts several weeks. After this stage, hair
will enter the shedding phase. Hair entering the resting phase loses its connection with the hair follicle. It loses weight and falls out within 2-4 months. New hair is produced from the hair follicle to replace the lost hair. In a healthy individual, 20% of the hair is already in the shedding phase. When this rate exceeds 20%, hair loss is pathological.
What are the causes of hair loss?
There are many reasons for hair loss. Genetic factors, systemic diseases (covid infection, HIV), stress, vitamin and mineral deficiencies, iron deficiency, imbalance in thyroid hormones, lichen and fungi that also affect the scalp, diseases such as acne, folliculitis, hormonal reasons, rapid weight loss, genetic predisposition, chemotherapy, burns, traumas, heavy metal poisoning and some medications used (e.g. birth control pills, antiepileptics, thyroid suppressant drugs).
Another cause of hair loss is cosmetic procedures such as hair dyes, exposure to high heat, use of chemicals to straighten the hair, ceramic hair straighteners and hair dryers. Making hair as a ponytail, which has become popular recently, or braiding tightly from the base also causes traction as it exposes the hair follicles to long-term trauma leading to hair loss and alopecia.
What is androgenetic alopecia?
Androgenetic alopecia develops as a result of the hypersensitivity of hair follicles to circulating androgens and based on genetic predisposition. On examination, thinning of the diameter of the hair strand is observed. In more advanced stages, the hair follicle disappears completely and baldness occurs. Androgenetic alopecia is seen in 80% of men and 50% of women up to the age of 70. In patients with androgenetic alopecia, increased activity of the 5-alpha reductase enzyme, which converts testosterone to dihydrotestosterone, has been observed. This increased enzyme is also responsible for the thinning of the hair strand. In men, it is manifested by hair loss at the vertex of the head and regression of the frontal hairline due to the increase in androgens with puberty. In women, the hair on the upper part of the head generally becomes sparse, while the front hairline is preserved. It has a pine tree-shaped shedding pattern. The reason for this shedding is increased response to androgens or genetic tendency. It can be seen especially in the post-menopausal period, adrenal gland tumors, polycystic ovary syndrome and during breastfeeding.