The use of OpenSource diets for studies
of osteoporosis allows the researcher to
test the effects of specific levels of
calcium and vitamin D, all free of
phytoestrogens.

Vitamin D is needed for the body to
absorb calcium. Vitamin D comes from

two sources: through the skin following direct exposure to
sunlight and from the diet. Without enough vitamin D, the body
is unable to absorb calcium from foods; thus, calcium will be
extracted from the skeleton. Estrogen also plays a role in
maintaining bone health.