Gray hair could play surprising role in cancer defense, study suggests

Why does hair turn gray? And how is that common hallmark of aging connected to a life-threatening disease? 

A new study may have pinpointed how going gray is connected to one of the deadliest forms of skin cancer.

Researchers at Tokyo Medical and Dental University, led by Dr. Emi K. Nishimura, found that pigment-producing stem cells in hair follicles respond to stress in dramatically different ways.

BREAKTHROUGH BLOOD TEST COULD SPOT DOZENS OF CANCERS BEFORE SYMPTOMS APPEAR

Depending on their environment...