The kidneys belong to the endocrine system and are responsible for filtering wastes and fluid from the blood, which are then excreted in the urine. The rate at which the kidneys function is referred to as the glomerular filtration rate. Those with kidney disease experience a decreased glomerular filtration rate and a gradual loss of kidney function over time. To keep the body healthy when the kidneys are not functioning properly, it is important to follow a proper diet.
Protein
Protein restriction is an important component of nutrition for kidney disease. The consumption of protein significantly increases the amount of wastes in the blood. When excess waste is present, it triggers the kidneys to begin filtration. If the kidneys are not functioning properly, this filtration puts excess pressure on them and can lead to decreased filtering ability over time. On the other hand, protein is an important part of building muscle, repairing body tissue and fighting infections, so it is important to consume adequate amounts, according to the National Kidney Foundation. The amount of recommended protein differs based on the severity of the specific condition. Someone with kidney disease should work with a dietitian to determine the proper amount.
Potassium
Potassium is an electrolyte, which means it is a mineral with an electrical charge. The kidneys are responsible for filtering out excess amounts of potassium from the blood so that electrical charge stays neutral. Diseased kidneys cannot properly filter potassium, which causes it to accumulate in the blood. Excess amounts of potassium in the blood can affect proper heart beat, according to the National Kidney and Urological Diseases Information Clearinghouse. Those with kidney disease should avoid consuming foods with high amounts of potassium, such as bananas, oranges, potatoes, dried beans and nuts.
Sodium
According to the National Kidney Foundation, kidney disease and high blood pressure are often related. Because sodium contributes to increased blood pressure, it should be limited in the diet. Those with kidney disease should avoid canned foods, frozen foods, processed meats, salted snack foods and added salt.
Importance of Calories
Calories give the body energy, help maintain proper weight and allow the body to use protein to build tissue. Those with kidney disease often experience weight loss, and because a diet for kidney disease limits a variety of foods, it is important to pay attention to calories and make sure that enough calories are being consumed. A dietitian may recommend an increase in simple carbohydrates, such as jam, jelly, honey and syrup.
Considerations
Kidney disease is usually characterized by a gradual decrease in kidney function. Because of this, specific dietary recommendations may change as kidney function worsens. It is usually beneficial for someone with kidney disease to work closely with a dietitian to keep track of nutrition goals.
