Patients with nephrotic syndrome are characterized by the presence of large amounts of urine protein, with 24-hour urine protein quantification exceeding 3.5 g and plasma albumin levels below 30 g/L. Patients with this disease need a low-salt diet, and it is not recommended that patients eat ordinary salt, not the so-called autumn rock salt or low-sodium salt, which may contain more potassium ions and are unsafe for patients with kidney disease. The daily salt intake of patients should be controlled at 3-6g, which is roughly equivalent to half of the daily salt intake of ordinary Chinese people, including salt in snacks and condiments, for example, soy sauce contains a lot of salt.