For years, doctors have told kidney stone patients to limit their calcium consumption on the grounds that calcium is a major component of stones. This is not only true for the general public, but also for many physicians. I have also cautioned my patients in this way. However, the problem arose recently while treating a special case, which was a case of bilateral knee pain predominantly, with significant pain at night, along with systemic symptoms. The ultrasound results of the physical examination showed stones in both kidneys, spleen and gallbladder, and the patient stopped all calcium supplements and medications to promote calcium absorption after the stones were found. However, the pain in the knee joint did not respond to almost all methods, even arthroscopy and joint irrigation, and the stones were increasing in size. Bone density test: no indication of severe osteoporosis. So it made me to look up the information, and after doing so, I felt that I was really limited, and here’s the thing. After years of research, medical experts from Harvard University in the United States found that this may be a big mistake in human understanding. They suggested that the way to reduce the risk of kidney stones is precisely to increase calcium intake. As you know, the diet, especially vegetables, contains a lot of oxalate, which is normally combined with calcium in the intestine to form calcium oxalate and excreted in the feces. If the intake of calcium in the diet is insufficient, it will cause excess oxalate to be absorbed into the blood through the intestinal lumen and eventually raised by the kidneys. If the body is in a negative calcium balance for a long period of time, the kidney cells will inevitably suffer from cellular paradoxical calcium in-flow damage, the kidneys will have reduced reabsorption and increased urinary calcium excretion. High calcium urine combines with oxalate in the urine to form large and small calcium oxalate stones. If calcium is not avoided, but calcium supplementation is taken, especially water-soluble calcium supplements, then it is combined with dietary oxalate in the gastrointestinal tract to form calcium oxalate excreted in the feces. In addition, adequate calcium supplementation reverses the negative calcium balance, the kidneys reabsorb properly, urinary calcium excretion is reduced, and the likelihood of stones is reduced. After reading the text of this study, I decided to start this patient on calcium supplementation and vitamin D and osteopontin, etc. The pain is slowly subsiding, but I don’t know if the stones in the organs will slowly disappear, I guess it is a long process. Old knowledge is constantly being updated and what people think is common sense or even axiomatic is not necessarily correct.