16 was the beginning of the grey hairs, at my temples and over my forehead, then proceeded quickly to the rest of my head. I was totally grey by 20. I have been coloring since my teens and appreciate the effect. It is the color that it was before with some highlights. It will be nice when I can get to an age where it feels appropriate for me to let it go natural; however, that time has just not come yet, give me the bottle.