Middle-aged and elderly patients with osteoporosis can take the following calcium supplements.1. Inorganic calcium can be taken, commonly used are calcium chloride, calcium sulfate, calcium carbonate and the like. These drugs are very inexpensive and have a very high calcium content. If the patient has no associated gastrointestinal symptoms when taking them, they can play a very good therapeutic role by taking such drugs. 2, you can take organic calcium, commonly used are calcium gluconate, calcium lactate and the like. These calcium preparations are less stimulating to the gastrointestinal tract, but the calcium content is slightly lower, but as long as they are taken in sufficient quantities, they can also play a very good therapeutic effect. 3, you can take active calcium, a liquid state of calcium preparations, its calcium content is very high, the absorption is also very good. 4, you can take a compound preparation containing calcium and vitamin D, in the clinical application is more calcium carbonate and vitamin D compound preparation.