Bad kidneys usually indicate abnormalities in the kidneys, such as proteinuria, elevated blood creatinine, etc. Diet should pay attention to the following aspects: 1, avoid high protein diet: emphasize a high quality low protein diet, that is, the total protein intake to maintain a low level. And high quality protein includes animal protein, such as meat, eggs, milk, vegetable protein in soybean nutritional value is also high; 2, to pay attention to sodium intake: because the kidneys are not well prone to hypertension, hypertension and will aggravate kidney damage, so pay attention to low salt diet. Daily salt intake should be controlled within 6g, and limited to 3g in severe cases, to avoid a high sodium diet; 3, to limit potassium intake: because kidney function declines are prone to hyperkalemia, and hyperkalemia is serious to a certain extent, it can affect the heart, causing arrhythmia, cardiac arrest, and even life-threatening. So pay attention to a low-potassium diet, such as bananas and oranges in fruits, and green leafy vegetables, which contain high potassium and can be partially removed by hot water; 4, to control the intake of phosphorus: mainly in food additives, preservatives containing phosphorus, so it is recommended that patients with poor kidney, pay attention to avoid processed foods, especially vacuum-packed food.