What Causes Hair Loss in Men?


Why? It's usually something you can blame on your family tree, but there are several other possible reasons.



Doctors don’t fully understand why certain hormonal changes cause hair follicles to shrink, or why the balding process gradually happens in the same pattern for most men. But it usually starts with a thinning of the hairline above your temples and crown.

Depending on your family history, male pattern baldness can start as early as your teens. Not only will your hair get thinner, but it may get soft, fine, and shorter.

Medical Issues

Temporary hair loss can be a sign of a medical issue, like anemia or thyroid problems. A diet low in protein and iron can also cause you hair to thin.

Hair loss could be a side effect of certain drugs you take for:

Radiation treatment or chemotherapy can cause widespread hair loss, but usually your hair will grow back with time, once the treatments end.

Stress or Shock

Sudden or excessive weight loss, a severe physical or emotional shock, surgery, or even fever and the flu can bring hair loss that could last several months.



Your Immune System

If you have sudden hair loss that leaves round bald spots about the size of a quarter in various places on your head, you may have a genetic condition called alopecia areata. It often begins in childhood. You’re more likely to have it if a close family member has it.

Your body’s own immune system attacks your hair follicles, causing small patches of hair to fall out. There’s no pain or sickness involved, and it’s not contagious. Your hair may grow back, but it may fall out again, too.


Impulse Control Disorder

Some people have an urge to pull out their own hair -- from the scalp, eyebrows, or someplace else -- a chronic condition known as trichotillomania. It could affect 1-2% of adults and teenagers.


Wearing a ponytail, braids, or cornrows where the hair next to the scalp is pulled tightly can cause temporary hair loss called traction alopecia. In addition, hot oil treatments and perms may damage your hair follicles.


There are a number of old wives’ tales about hair loss, most of which are false. For example:

  • Neither does swimming in a chlorinated pool or salt water.
  • Sunscreen won’t make your hair fall out, but it will protect the areas where your hairline has receded.
  • Hair dryers may cause your hair to be more brittle, but they won’t lead to permanent hair loss.

WebMD Medical Reference Reviewed by Melinda Ratini, DO, MS on March 9, 2018



American Academy of Dermatology: “Hair Loss.”

Mayo Clinic: “Hair Loss.”


Mental Health America: “Hair Pulling.”


Genetics Home Reference: "Androgenetic alopecia."

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