WHY YOUR HAIR IS GRAYING   Your hair eventually loses its color.  This starts happening as early as your 30s or 40s. (Heck, with me it started in my 20s.) Gray hair is actually hair with reduced melanin. White hair completely lacks it. Now a study on mice has come along that is probably relevant to humans. These findings might be a step toward preventing or actually reversing the graying process. (Still, you can always dye your hair.) Here are excerpts from the April 19, 2023 New York Times article by Kate Golembiewski, Your Hair is Going Gray. This Glitch...