Here in the United States we have a saying "oh, that's a big hairy deal". That may mean something is very important, or if said with the right tone of voice, the phrase means sometime is highly overrated in importance. In the case of Vitamin D, there may be some literal truth to this saying. A few years ago, the hair on my legs all but stopped growing. When I noticed my Vitamin D level was lower than desired (although not officially deficient) and I started taking supplements, lo and behold, the hair on my legs started growing again. It appears that Vitamin D may be related to body hair growth! I'm wondering. Will I turn into an American hair ball? Inquiring minds want to know.