P h o s p h o r u s
Is a component of bones (see Apatite, ATP), cells, in energy processing and many other functions.
700 mg RDA - 4000 mg UL
RDA (recommanded dietary allowances) per day 
UL (tolerable upper intake level) per day 
 Food and Drug Administration (FDA)
 Dietary Reference Intakes: Tolerable Upper Intake Levels, Food and Nutrition Board, Institute of Medicine, National Academies, 1997