Here are some possible causes of hair loss in teenagers.
Genetics
Androgenetic alopecia is a genetic cause of hair loss, called male-pattern baldness or female-pattern baldness. This is a predictable pattern. In men, it usually manifests as a receding hairline into an M, V, or U shape and gradual baldness on the top of the head. Women usually notice gradual thinning of one section of their hair. Hair loss typically begins in adulthood, but may also begin during adolescence.
Alopecia Areata
Alopecia areata is an autoimmune condition that causes hair to fall out in patches. Autoimmune conditions develop when your body mistakes your own healthy cells as invaders. In the case of alopecia areata, your immune system attacks your hair follicles. You may notice hair loss on your scalp, eyebrows, eyelashes, or body. Alopecia areata affects about 2 percent of the population at some time in their lives. In most people it develops before the age of 30, sometimes it may start in childhood.
Malnutrition
Malnutrition is a lack of proper nutrition that can be caused by not eating enough, eating too much, or not getting the right balance of nutrients. Some possible causes are lack of access to food, dietary imbalance, eating disorders or digestive conditions. Deficiency of the following nutrients can cause hair loss, including:
Thyroid
Thyroid conditions that cause under- or over-production of thyroid hormone can cause hair loss or brittleness. Hair loss due to thyroid conditions usually shows up as uniform thinning across your scalp. Hair loss is most common in people suffering from long-term thyroid disease. Hair health can remain good with proper treatment.
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Lupus
Lupus is an autoimmune condition caused by your immune system targeting your tissues and organs. Lupus can cause symptoms such as joint pain, fatigue, and hair loss. Hair gradually starts thinning in people suffering from lupus.
Polycystic Ovary Syndrome
Polycystic ovary syndrome is a women's health problem. The production of hormones such as testosterone is normal in women. But when they produce too much, it can lead to symptoms like menstrual cycle disruption, acne and hair thinning, and treating the hormonal imbalance can lead to hair regrowth.
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