I read a study years ago (I'm too lazy to look it up) reporting the best outcomes for women and bone health as they aged were a result of moderate calcium and higher than average protein intake.
Here's one:
http://ajcn.nutrition.org/content/87/5/1567S.full
CONCLUSION
Despite a widely held belief that high-protein diets (especially diets high in animal protein) result in bone resorption and increased urinary calcium, higher protein diets are actually associated with greater bone mass and fewer fractures when calcium intake is adequate. Perhaps more concern should be focused on increasing the intake of alkalinizing fruits and vegetables rather than reducing protein sources. The issue for public health professionals is whether recommended protein intakes should be increased, given the prevalence of osteoporosis and sarcopenia. Currently, little or no attention is paid to ensuring adequate protein intake for elderly fracture patients. In the hospital setting, there should be nutrition protocols in place for hip-fracture patients that include higher protein and calcium intakes. Moreover, health professionals may need to be reeducated about the important role of protein in bone health.