the daily intakes for eight age-sex groups ( infants , young children , and male and female teenagers , adults , and older adults ) of nine nutritional elements ( sodium , potassium , calcium , phosphorus , magnesium , iron , zinc , copper , and manganese ) were obtained by laboratory analysis of the food and drug administration 's 234 total diet study ( tds ) foods and by use of the usda nutrient data base for standard reference .
C0013879
elements
C0031705
phosphorus