Hair loss, baldness or alopecia results when hair loss occurs at an abnormally high rate, while hair replacement occurs at an abnormally slow rate, or while normal hairs are replaced by thinner and shorter ones.
Some causes of excessive hair loss include:
- A family history of baldness (especially male-pattern baldness)
- Certain diseases, e.g. diabetes mellitus, thyroid disorders
- Scalp infection or skin damage
- Some medications, e.g. anti-cancer drugs, hypotensive drugs, anti-depressants
- Poor nutrition, e.g. inadequate protein or iron