@cathy: I get an injection every 6 months, Prolia, for osteoporosis. Each time, before the injection, I am required to get a blood test to ascertain my blood calcium level. Mine is always low, barely meets the requirement of calcium to get the injection. I have celiac disease and even though I avoid wheat, rye, and barley like the plague (an old-timey expression) the tips of my small intestine villi are damaged from the years I had this disease and wasn't diagnosed. So even though I follow a strict gluten free diet, I still have absorption issues. Because of this my endocrinologist wants me to take 1000 mg. of a calcium citrate supplement in addition to what I get in my diet. A friend of mine, who is also on Prolia injections, but who does not have celiac disease, was told by her Stanford doctor to take a 500 mg. calcium supplement in addition to what she gets in her diet to meet the calcium threshold because it is imperative that you get enough calcium when on Prolia. Otherwise there can be negative health consequences. Thank you for your informative post.