Calcium citrate is a kind of health food, while calcium carbonate belongs to a kind of medicine, so calcium citrate and calcium carbonate are not comparable. Calcium carbonate is a common clinical calcium supplement drug, belongs to the inorganic acid calcium, the price is cheaper, the calcium content is also higher, but should be taken at mealtime in order to be better absorbed by the body. The side effect of calcium carbonate is that it will have an irritating effect on the gastrointestinal tract, causing abdominal discomfort, constipation, etc. Therefore, people with normal gastrointestinal function can choose calcium carbonate for calcium supplementation, which is cheap and affordable. Contraindications are prohibited for patients with hypercalcemia, hyperuricemia, and kidney stones. The use of drugs must follow the doctor’s instructions, not blindly use drugs on their own, so as not to cause adverse consequences.