February 4, 2020 Edition Stress can cause hair to gray prematurely by affecting the stem cells that are responsible for regenerating hair pigment, researchers found. | In a small study, a drug approved to treat overactive bladder boosted brown fat activity and improved glucose metabolism in healthy women. | Experimental treatments in animal models of HIV led to the viruses emerging from their hiding places, a first step needed to make HIV vulnerable to the immune system. | Popular Stories Connect with Us |