What is the kidney diet?

If you have chronic kidney disease (CKD), your kidneys are not able to remove waste products and excess fluid from your body in the way that healthy kidneys do. Your diet can have a significant impact on your body’s overall health and the progression of CKD, since certain foods can add to the accumulation of waste products and extra fluid in your blood. The kidney diet is a plan for eating that supports your kidney health.

If you have recently been diagnosed with CKD, a renal dietitian can help you determine which foods are best for you.

Typically, a kidney diet is:

Low in sodium
Low in protein
Low in phosphorus

Sodium

Because high blood pressure can lead to kidney disease, it is recommended that you limit your sodium (salt) intake to help control your blood pressure. In addition, ingesting less sodium will help reduce the amount of fluid that your body retains.

Protein

Protein can help lower the blood sugar impact of meals and keep hunger pangs away, but when your kidneys are not healthy, eating too much protein can put a strain on them. A kidney-friendly diet limits the amount of protein you eat to help slow the progression of kidney disease.

Phosphorus

Often people with kidney disease will have high levels of phosphorus; therefore, it is necessary to monitor the level of this mineral in your body and limit intake of high-phosphorus foods. Your health care provider may also prescribe a phosphorus binder. The phosphorus binder helps stop your body from absorbing phosphorus from food.

When your kidneys do not remove enough phosphorus from your blood, your bones may begin losing calcium. Taking a phosphorus binder and keeping phosphorus levels in a healthy range helps prevent bone disease by keeping calcium levels from declining.

Potassium

If your kidneys are not functioning properly, your body may not be able to eliminate potassium as it should. That’s why your health care provider will check the levels of potassium in your body on a regular basis to ensure that they are not too high. If levels of potassium in your blood rise above normal, you could experience harmful heart rhythms. In you’re in the early stages of kidney disease or are on peritoneal dialysis, you may not need to limit the amount of potassium you consume.

Your doctor or renal dietitian will review your blood work with you and recommend your individual kidney diet based on your lab results.

Eating for kidney health

If you are trying to restrict the amount of sodium in your diet, there are some easy things you can do:

Learn to decipher food labels. Skip foods whose ingredients include sodium or monosodium glutamate (MSG).
Avoid eating processed and cured foods, including deli meat, bacon, ham, smoked meats and processed cheese, since they are all typically high in sodium.
Watch out for other high-sodium foods, such as pickles, olives, snack foods and soups.
Skip the drive-through, since “fast foods” are notoriously high in sodium.
Instead of adding salt to your food at the table, use healthier seasonings such as herbs and spices or a little squeeze of lemon for extra flavor.

Protein is necessary for strong bones and muscles, but too much of it can cause your kidneys to work harder. Here are some tips for managing the protein in your diet:

Begin by consulting your renal dietitian to determine how much and what kinds of proteins you should eat
Protein is found in meat and dairy products, but it also can be found in vegetables, breads and cereals. You’ll need to become aware of these lesser-known sources of protein.
Select high-quality protein, including chicken, fish, cheese, eggs and lean meats.

Keeping phosphorus levels healthy means watching your intake of these foods and beverages:

Limit your consumption of dairy products
Limit nuts, peanut butter, beans, seeds or peas
Limit cocoa, beer or cola drinks

When reading food nutrition labels, lookout for these ingredients, which all refer to phosphorus: phosphoric acid, dicalcium phosphate, monocalcium phosphate, pyrophosphates, hexametaphosphate, polyphosphates and sodium phosphate.

If you need to limit your potassium intake:

You may be able to use a salt substitute instead of table salt, but be sure to check with your health care provider first, since many are high in potassium.
You may be better off using herbs and spices and skipping the “salt” altogether.

If your health care provider says you need to watch your fluid intake, keep these tips in mind:

Your fluid intake is not just about water and other beverages. Any food that is liquid at room temperature counts. This includes ice cream, gelatin and soup.
Note that some fruits and vegetables, such as oranges, grapes, apples, lettuce and celery, also contain water and should be restricted.

Your health care team can help you get on track with your diet, so you can support your health through good eating. It is likely that your kidney diet will change as time goes by and your kidney function and treatment changes.