"Can you tell me why our hair turns gray?"

You've got me stumped there. I can' tell you why our hair turns gray, but I can tell you how.

Our hair color comes from melanin. This is a pigment produced by melanocyte stem cells at the base of our hair follicles. As we get older, these cells start to die, so the new hair that grows in has no pigment.

The result—gray or white hair.

Now you're wondering why the cells die—that's what we don't know, despite a whole lot of research.

Stress or vitamin deficiency may have some affect in speeding up the process, but mostly it's genetics that determines when a person will go gray.

So, if you find a gray hair earlier than expected, don't worry. Going gray is usually not a reflection on your health or life expectancy.

It just means you look more distinguished.