If you want strong bones, get your daily calcium intake from dietary sources such as milk, yoghurt and cheese, not from supplements. After studying 168 healthy postmenopausal women consuming calcium as either a supplement, from dietary sources or as a combination of supplements and diet, researchers from the US found higher bone densities in the women who consumed most of their daily calcium from dietary sources. This even held true when the supplement takers had a higher average calcium intake than those consuming dietary sources of calcium.When researchers looked at the women's levels of the oestrogenic metabolites, they found that the women with dietary sources or mixed sources of calcium (combination of diet and supplements) had higher levels of the active metabolite 16-hydroxyestrone than women who received most of their calcium from supplemental sources. This correlates with a greater bone mass density and thus more favourable effects on the bone health of postmenopausal women, than calcium from supplements. The mechanisms which underlies these effects are still unknown, but it's always best to get your vitamins and minerals from food because they contain all the extra benefits that supplements don't.