I remember reading somewhere that people who started drinking green smoothies (like, really green -- kale + romaine + spinach + pear + avocado, etc.) had a major improvement in overall health and a side benefit of their hair turning dark again, after having gone gray. It was credited to the better absorption of HCL in the greens by the digestive system, which required some healing from the greens to get there.

Ann Louise Gittleman, I think. The Fat Flush lady. Or maybe it was that lady who espouses the green smoothie lifestyle. I can't recall her name. It's Russian. I do like some of her smoothie recipes, but not the recommended two quarts a day.

Roxy