In the normal state, blood has no business anywhere except in the confines of the heart and blood vessels and in the sinusoids of the marrow, liver, and spleen. Of the average 5 L of blood, only 2.25 L, or 45%, consists of cells.
Take-away: Calcium and magnesium may best be taken in the evening with food or before nighttime sleep. Since zinc should not be taken with calcium and apart from iron, it is most useful if taken earlier in the day either slightly before/after food. Iron should ideally be taken on an empty stomach and separately from other multivitamin/multimineral combinations.
Adult men and adolescent boys between 14 and 18 years of age should aim to consume about 11 milligrams of zinc daily, while adult women 19 years old and over need about 8 milligrams. Girls between 14 and 18 require 9 mg per day. Pregnant women and nursing women require respectively 11 to 12 milligrams and 12 to 13 milligrams per day. Food Sources of Zinc The best way to avoid consuming too much zinc is to avoid taking dietary supplements.