Kidney stones are a common disease of the urinary system and are more common in men than in women, mostly occurring in young adults, and there is no significant difference in the incidence of left and right side. The main cause of kidney stone formation is diet. It is caused by excessive intake of relevant components in the diet that can form stones. The following are the causes of kidney stones. 1. Excessive protein: Laboratory analysis of kidney stone components revealed that calcium oxalate accounted for 87.5% of the stones. The source of such a large proportion of calcium oxalate is because protein contains glycine and hydroxyproline, the raw materials of oxalic acid, in addition to protein can also promote the absorption of calcium by the intestinal function. If high protein foods are often consumed in excess, they cause a general increase in the composition of calcium, oxalic acid and uric acid in the kidneys and urine. If the excess calcium, oxalic acid and uric acid are not discharged from the body through the kidney function in a timely and effective manner, the conditions for kidney stones and ureteral calculi will be formed. This is the main reason for the increased incidence of kidney stones in economically developed countries in the world today. 2, too much fat intake: a variety of animal meat, especially fatty pork, are fatty foods. Eat more fat in the body is bound to increase, fat will reduce the intestinal tract can be combined with calcium, thus causing an increase in the absorption of oxalate, if once the excretory function failure, such as sweating, drinking less water, less urine, kidney stones are likely to form in this case. Therefore, doctors often say, in order to prevent getting stone disease, hot days to drink more water, eat a lot of oil and water food, also drink more water, in order to promote the smooth urination, dilute the urine composition, it reduces the risk of getting stones. 3, purine metabolism malfunction: animal offal, seafood, peanuts, beans, spinach, etc., all contain more purine components. When purine enters the body, it is metabolized, and the end product of its metabolism is uric acid. Uric acid can contribute to the precipitation of oxalate in the urine. If too much purine-rich food is consumed at one time, and the metabolism of purine is out of order, oxalate will be deposited in the urine and form urinary stones. 4, increased sugar: sugar is an important nutrient for the human body, and should be added regularly in moderation, but too much at once, especially lactose, will also make the formation of stones to create conditions. Experts found that: whether normal people or stone patients, after consuming 100 grams of sucrose, after 2 hours to check their urine, found that the urinary concentration of calcium and oxalic acid are increased, if lactose is taken, it can promote the absorption of calcium, more likely to lead to the accumulation of calcium oxalate in the body and the formation of urinary stones. 5, too much oxalic acid accumulation: the large accumulation of oxalic acid in the body is one of the factors that lead to kidney urinary stones. Such as spinach, beans, grapes, cocoa, tea, oranges, tomatoes, potatoes, plums, bamboo shoots and other things that people commonly love to eat, is precisely the food containing high oxalic acid. Doctors found through research: 200 grams of spinach, containing 725.6 mg of oxalic acid, if a person will eat all 200 grams of spinach at once, 8 hours after eating, check the urinary excretion of oxalic acid for 20-25 mg, equivalent to the average total amount of oxalic acid excreted by normal people in 24 hours.