(Ca) | 1000–1200 mg | 800–1200 mg | Typical diet is inadequate, averaging 500–850 mg. | | Phosphorus
(P) | 1250 mg 9–18 yrs
700 mg adults | 800–1200 mg | Inadequate intake is rare except in elderly and malnourished. Excess intake common with use of processed foods and soft drinks — ~1500 mg/day in men and ~1025 mg/day in women. | | Magnesium
(Mg) | 420 mg adult males
320 mg adult females | 400–800 mg | Intake generally inadequate among all ages, sexes, and classes except children under the age of 5; 40% of total population and 50% of adolescents consume 66% of RDA; and 56% of all Americans have intakes below Estimated Average Requirement (EAR). | | Chromium
(Cr) | 30–35 mcg, adult males
20–25 mcg, adult females | 200–1000 mcg | Common intake in the US is 50 mcg or lower. | | Silica
(Silicon — Si) | No values set to date | 5-20 mg | Intake significantly higher in men (30–33 mg/day) than in women (~25 mg/day), yet generally suboptimal. Silica is the first element to go in food processing. | | Zinc
(Zn) | 11 mg adult males
8 mg adult females | 12–30 mg | Average intake is 46–63% of RDA. Marginal zinc deficiency is common,