Asked by: Sean Miller, by email

Male pattern baldness is caused by the hormone DHT or dihydro-testosterone. This has many other effects on the body and it is thought to inhibit hair loss in the nostrils so that each shaft has a longer growing phase. But the exact mechanism is still not well understood.


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luis villazon
Luis VillazonQ&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.