Hair loss, also known as alopecia, refers to the loss of hair on the body. There are various types of hair loss, all of which tend to differ in their underlying causes, prevalence, and the pattern in which hair is lost. Common types of hair loss include male- and female-pattern hair loss (collectively referred to as androgenetic alopecia; AGA), alopecia areata, telogen effluvium, and anagen effluvium.[1]
What is hair loss?
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•Last Updated: October 27, 2025
Hair loss, or alopecia, is the loss of hair on the body. The various types of alopecia include androgenetic alopecia, alopecia areata, telogen effluvium, and anagen effluvium.