title: I've read that too much vitamin A can weaken bones.  How much is too much?
mesh_terms: D015519:Bone Density / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006293:Health Promotion / Q000379:methods; D006620:Hip Fractures / Q000139:chemically induced / Q000517:prevention & control*; D006801:Humans; D014801:Vitamin A / Q000008:administration & dosage* / Q000009:adverse effects*; D019207:beta Carotene / Q000008:administration & dosage
chemical_list: D019207:beta Carotene; D014801:Vitamin A