In recent years, as people pay attention to high blood pressure, low sodium salt has occupied most of the supermarket salt shelves and appeared on more and more people’s dinner tables. What people don’t know is that low sodium salt is not suitable for everyone, and patients with kidney disease need to use low sodium salt with caution. Low sodium salt is made from sodium chloride and potassium iodate, with a certain amount of potassium chloride and magnesium sulfate added to improve the balance of sodium, potassium and magnesium in the body. Low sodium salt can reduce the risk of hypertension and cardiovascular disease, so low sodium salt is suitable for middle-aged and elderly people and patients with hypertensive heart disease to eat for a long time. While it is true that patients with kidney disease should eat a low sodium diet if they have high blood pressure and edema, it is not recommended to eat low sodium salt. This is because low sodium salt contains more potassium, and when the kidney function of kidney patients is impaired, they cannot excrete more potassium effectively, and the accumulation in the body will cause high blood potassium, which will easily lead to symptoms such as arrhythmia, numbness and fatigue of the limbs, and even life-threatening severe hyperkalemia, which may lead to cardiac arrest. As kidney function gradually declines, the risk of hyperkalemia increases. Hyperkalemia is not uncommon in patients with renal failure, whether they are not yet on dialysis or already on hemodialysis or peritoneal dialysis. In turn, when doctors pursue the cause of their hyperkalemia in the clinic, low sodium is a latent risk factor that is highly overlooked by everyone. Patients often know that bananas, oranges, and leafy greens are high-potassium foods, but fail to notice that low-sodium salt at the table is also one of the high-potassium foods. Low sodium salt can be considered only in a few patients with persistent low blood potassium and poor eating conditions who need oral potassium supplementation therapy and more high potassium foods, but it is important to test blood potassium levels regularly to avoid supplementation into hyperkalemia. Therefore, patients with kidney disease should not take low sodium salt for granted because they think that a low sodium diet is beneficial. Instead, they need to consult their doctor and decide whether they can take low sodium salt under the guidance of their doctor, taking into account their blood potassium level and kidney function.