At what age is it normal for my private area hair to turn gray?

Most people notice their first gray hairs in their thirties (age 30 for men, age 35 for women, on average). Those hairs are usually on the head. Body hair tends to turn gray a little bit later, and may not ever turn gray in some people. Hair turns gray when the melanocytes in the hair follicle slow down their production of pigment, causing hair color to turn gray initially, then white when there is no pigment left.