What do your kidneys do?
Your kidneys are two bean-shaped organs behind your stomach in the middle of your back, on either side of your spine. Each kidney is about the size of your fist. Your kidneys do some of the most important jobs in your body, such as:
- Filtering and removing waste
- Helping control blood pressure
- Cleaning and controlling the amount of blood in your body
- Keeping the body's balance of water, salt, and acid constant
- Making hormones that help bone marrow make red blood cells
What happens when the kidneys are not working the way they should?
If something happens to change the way the kidneys work, it is usually because of a condition that has been attacking the kidneys for a long time. This may lead to chronic kidney disease that generally affects both kidneys. This might be something you were born with. It could be a problem that developed over time, possibly due to long-time use of over-the-counter pain relievers. There may be no symptoms of kidney disease at first. When the kidneys are not working correctly, the body's waste and excess fluids build up. This can harm the body.
Some symptoms of kidney disease may be:
- Edema (fluid buildup) in the tissues
- A change in urination (frequent, painful, or difficult)
- Shortness of breath
Some of the things that can injure the kidney and lead to chronic kidney disease are:
- High blood pressure
- Glomerulonephritis (inflammation of the kidneys' filtering units)
- Polycystic kidneys (cysts that enlarge over time)
- Kidney stones
Kidney disease may progress to kidney failure if:
- The disease has not been diagnosed early enough
- The disease has not been treated early enough
- The patient has not responded to treatment
What is Dialysis?
Dialysis is a process for removing waste and excess water from the blood and is used primarily to provide an artificial replacement for lost kidney function in people with renal failure.
Dialysis may be used for those with an acute disturbance in kidney function (acute kidney injury, previously acute renal failure), or progressive but chronically worsening kidney function–a state known as chronic kidney disease stage 5 (previously chronic renal failure or end-stage renal disease). The latter form may develop over months or years, but in contrast to acute kidney injury is not usually reversible, and dialysis is regarded as a "holding measure" until a renal transplant can be performed, or sometimes as the only supportive measure in those for whom a transplant would be inappropriate.
What's a Kidney Diet?
The kidney diet, also known as the renal diet, is a set of guidelines for people with kidney disease. The types of foods prescribed depend on the level of kidney failure the patient is experiencing, but generally, the diet involves controlling the amount of sodium, potassium, phosphorus, protein, and fluid that a person ingests. People with kidney disease should be in consultation with a renal dietitian. Before making any changes to your diet, make sure you discuss them with your doctor or dietitian.
The Renal Diet- Phosphorus
Phosphorus is a mineral that works with calcium to keep your bones healthy and strong. Phosphorus is needed by the body for building and maintaining bones and teeth and for normal nerve and muscle function. When kidney function declines, the body has a difficult time keeping phosphorus and calcium in balance. As a result of this imbalance, the body cannot get rid of excess phosphorus (phosphorus levels increase) and the body cannot take in enough calcium (calcium levels decrease). To try and correct this imbalance the body will “steal” calcium from the bones, which makes the bones weak. Problems associated with high phosphorus levels include itchy skin, bone and joint pain, and brittle bones.
Foods that are high in phosphorus include:
- Cola Drinks
- Peanut Butter
- Chicken/beef liver
- Ice Cream
Lower phosphorus food substitutes include:
- Non-dairy milk substitute
- Non-cola soda
- Zucchini squash
- Hard Candy
A large serving size of a low phosphorus food can become a high phosphorus food.
If your phosphorus level remains high, your doctor may prescribe a phosphate binder for you to take. This medication will bind with the phosphorus in the food you eat and prevent phosphorus from being absorbed in the body. It is important that you take this medication exactly as instructed by your doctor.
The Renal Diet- Potassium
Potassium helps to keep your nerves and muscles, especially your heart, working properly. Potassium is a mineral and can be found in many foods. The kidneys are responsible for helping to keep the correct amount of potassium in your body. It can be very dangerous if your potassium level is too high. Too much potassium can make your heart beat irregularly or even stop without warning.
Foods that are high in potassium include the following:
- Fruits, Vegetables
- Bananas, Broccoli, Chocolate
- Oranges, Potatoes, Coffee (limit to 2 cups per day)
- Cantaloupe, Tomatoes, Salt Substitute
- Prunes, Mushrooms, Bran & bran products
- Raisins, Greens, Apricots
Low-potassium foods include the following:
- Fruits, Vegetables
- Apples, Beans (green or wax), Rice
- Grapes, Cucumber, Noodles
- Pears, Onions, Cake
- Watermelon, Lettuce, Cereal
- Cranberries, Carrots, Bread & bread products
It is important to remember that almost all foods contain potassium. Serving size will determine whether foods are a low, moderate, or high potassium level. A large serving size of a low potassium food can become a high potassium food.
The Renal Diet- Protein
Diet plays an important role in the management of kidney disease. The diet your physician will ask you to follow will be based upon your level of kidney function, your body size, and any other medical conditions you may have. Your diet may be helpful in delaying the need for dialysis. Protein is needed to maintain muscles, aid in building resistance to infections, and repair and replace body tissue. As your body breaks down protein foods, waste products called urea are formed. As kidney function declines, urea builds up in the bloodstream. Eating too much protein may cause urea to build up more quickly. This will make you feel sick. Eating less protein may be helpful in reducing your blood urea levels. Reducing protein intake must be monitored by your doctor and dietician.
Examples of foods high in protein are:
- Milk Products
Foods low in protein includes the following:
- Fresh beans (pinto, kidney, navy)
You need both high-quality and low-quality protein in your diet. Your physician will determine how much protein should be in your diet.
The Renal Diet- Sodium
Sodium is needed by the body for many functions such as controlling muscle contractions, balancing fluids, and controlling blood pressure. Healthy kidneys remove excess sodium in the urine. As kidney function declines, sodium and fluids may accumulate in your body. Fluid retention may cause swelling in your eyes, hands, and/or ankles. To keep your sodium level in balance, your doctor may ask you to limit the sodium in your diet.
Foods high in sodium include the following:
- Table salt
- Bouillon cubes
- Potato chips
- Cold Cuts
- Canned, dehydrated, or instant soup
- Canned vegetables
- Processed dinner mixes (such as Hamburger Helper, Rice-a-Roni)
- Season with a variety of spices like garlic and oregano
- Use lemon