I am 70 and had 3 Reclast infusions over 6 years. The Reclast put me back in osteopenia range, from early osteoporosis. I didn't want to take biphosphonate pills due to side effects, and with the infusion I was just tired for a couple of days. The real risk from osteo is broken bones, and I bike and lot so... I lift weights, take calcium/magnesium citrate (helps absorption). Calcium in vitamins is from the sea in that it is from limestone, which is ocean derived. Vitamin D increases absorption in the GI tract, as does eating the calcium with food.