I am talking about 草酸钙结石 and also 结石 in general.

Prevention of recurrent kidney stones is very important. Unfortunately, there are a lot of unknowns in this filed. Some recommendations may not be evidence based.

I can understand why your doctor makes such a recommendation to you. What your doctor said makes sense. I also recommend same thing to my patients. But there is only scant evidence there to support such a recommendation. Having said that, however, some foods are high in oxalate and those should be avoided (eg spinach, rhubarb). In addition, some nuts and legumes are also high in oxalate and the intake should be limited (eg peanuts, cashews and almonds).

Increasing dietary fruits and vegetables may reduce the risk of calcium oxalate stone formation, particularly in patients who self-select a diet that is low in fruits and vegetables.

In prospective observational studies of individuals who have never had a stone, higher dietary oxalate only slightly increased the risk of incident stone formation in men and older women; there was no association in younger women. Because of the documented health benefits of many foods that are traditionally considered high in oxalate (but still 10 mg or less per serving), strict oxalate restriction does not seem to be supported.

hopefully，the above information will make the issue more clear.