Recently, several patients came to see me because of a large number of crystals inside the kidneys, they were very nervous and hoped that I could introduce the knowledge and solutions in this regard. Crystals in the kidney are actually some crystalline substances in the blood (such as calcium salt, urate, oxalate.) The flow through the kidneys is stagnated, and a large number of crystals can be seen in the renal tissues (mainly in the renal pelvis and renal interstitium) by ultrasound test as an antiphlogistic shadow. Most of these crystals are oxalic acid, uric acid, cystine and other water-insoluble substances in the body. They have little effect on the human body if they stay in the kidneys for a short period of time, but if they accumulate for a long period of time in the kidneys, more and more stones will be formed, and most of the kidney, ureteral, and bladder stones go through this process. What is not clear to the general public is that some components of the crystals (such as uric acid, oxalic acid) have a strong pro-inflammatory response and trigger the role of human tissue (blood vessels, kidneys) fibrosis, once they are deposited for a long time, they will cause inflammatory reaction of the surrounding tissue, stimulate tissue fibrosis, thickening of the blood vessel wall. Therefore, the long-term presence of intrarenal crystals is a hidden danger to the health of the kidneys and must be taken seriously. Nowadays, when people talk about family and social security, they often say: “fire, burglary and tabloid prevention”; similarly, medical science also emphasizes on human health: “lowering blood pressure, lowering lipids, lowering uric acid (oxalic acid)”. Research has proved that the main component of the crystals or kidney stones in our body is calcium oxalate, especially more than 80% of kidney stones are calcium oxalate. The reason why the incidence of calcium oxalate stones is high has a very close relationship with the dietary habits of our countrymen. Long-term consumption of large amounts of food rich in oxalic acid, oxalic acid through the kidney excretion process is very easy to form crystals in the acidic environment, they will be like the river and the sea in the flow of sediment on the way to precipitation, accumulation to a certain extent, the formation of stones. Rich in high oxalic acid food mainly spinach, beans, grapes, cocoa, oranges, tomatoes, potatoes, plums, bamboo shoots, etc., these ingredients are often on our table, usually consume attention to more water, or supplement some vitamin B6, is conducive to the removal of oxalic acid. Another reason for the high incidence of kidney crystals is a diet that is too salty. High sodium diet can affect the reabsorption of calcium, calcium in the urine that is the opportunity to converge with oxalic acid and uric acid, forming crystals or stones. Uric acid mainly comes from high purine, high protein food, if long-term high purine or high protein diet, will inevitably lead to increased levels of uric acid, they will also be like oxalic acid with the body of calcium combined to form crystals. High purine food mainly from animal offal, seafood, thick broth, peanuts, beans, spinach, etc., purine into the body after metabolism, its final product is uric acid. There is another reason that cannot be ignored for the increase of crystallization in the kidney is that the water consumption is too low, and there is not enough urine to remove these body wastes out of the body. Therefore, the easiest way to reduce kidney crystals is to control your mouth, learn how to eat; drink more water, master how much urine should be excreted every day, in principle, oxalic acid or uric acid food eaten, you should increase the amount of urine or alkalize the urine so that it does not precipitate, and excreted from the body as soon as possible. It is also worth mentioning that some herbs are also rich in oxalic acid, such as: rhubarb, polygonum multiflorum, ginseng, ginseng, American ginseng, fennel, clove, gardenia, elm, dandelion, hawthorn, mistletoe, white peony, honeysuckle, wu juju, rhizoma ligustici chuanxiong, he shouwu, huzhong, panax ginseng. These herbs are not a big problem for short-term use, but if they are taken for years and years, the level of oxalic acid in the urine and the presence of crystals in the kidneys should be checked regularly, and preventive measures should be taken proactively once they are detected.