basic things to remember, A D and E need fat, C and B are water soluble, Zinc cancels out Calcium, there is probably over use of Calcium, and Magnesium is where the shortages are. Be careful with iron supplements, if you eat meat, you are probably good there, men need less than women. You dont need a lot of bottles unless you are treating a condition, and then it could get expensive. B vitamins work together, so, a B supplement with C and Zinc, a cal-mag supplement, selenium, and anti oxidants. Cant take zinc and calcium together, iron has to have vitamin C to absorb.