MedlinePlus Health Topics
disease topic
Patient-friendly
Hair Problems
Source: MedlinePlus Health Topics, U.S. National Library of Medicine
Last synced 8/14/2026Status: primary verified
The average person has 5 million hairs. Hair grows all over your body except on your lips, palms, and the soles of your feet. It takes about a month for healthy hair to grow half an inch. Most hairs grow for up to six years and then fall out. New hairs grow in their place. Hair helps keep you warm. It also protects your eyes, ears and nose from small particles in the air. Common problem with the hair and scalp include hair loss , infections, and flaking .
Educational only
This information is for general education and is not medical advice. Always talk to a licensed U.S. clinician about your situation, medications, or treatment decisions.