Your kidneys are two matching organs that sit just below your ribcage on each side of your spine. Their job is to filter both waste and toxins out of your bloodstream. Much of this waste comes from the food that you eat. However, if you have chronic kidney disease (CKD), your doctor may advise you to change your diet to improve your kidney function. You may need to eat less of or completely avoid some foods. It can help to remember that you aren’t alone — 37 million Americans have kidney disease.
The four things you may need to watch and/or limit are potassium, phosphorus, protein, and sodium. While each of these nutrients and proteins is important for your body’s functions, too much of them can be dangerous for your kidneys if you have CKD. It’s largely about finding a healthy balance, and your doctor will help you determine a diet that works well for you. As you’re working with them to learn more, take a look at the information below to understand what to anticipate.
Foods That Are Low in Potassium and Phosphorus
A healthy diet can include fruits, vegetables, and grains. However, some of these can be high in potassium and phosphorus, making them unsuitable for a kidney diet. Some helpful options include fruits like apples, grapes, and strawberries; vegetables like cauliflower, onions, peppers, and lettuce; and grains like pasta, French or sourdough breads, corn and rice cereals, and unsalted popcorn.
Fruits, veggies, and grains that are high in potassium and phosphorus include many melons like honeydew and cantaloupe, bananas, avocado, prune juice, orange juice and oranges, tomatoes, all kinds of dried beans, winter squash, kale, cooked greens, broccoli, and nut butter.
Kidney-Friendly Proteins
Protein is still important for you, even with kidney disease. Your doctor can tell you the amount that you should get in your diet, and it’s likely a smaller amount than what people who aren’t on kidney diets consume. This amount may change if you’re on dialysis because dialysis removes protein from your bloodstream for you. Your medical team can tell you if this happens, so feel free to ask them, but it’s wise to avoid making the change without their input.
Some good sources of protein are egg whites, poultry (like chicken and turkey), and fish. You do need protein to build muscles, heal wounds, fight infections, and perform other bodily functions that keep you healthy. Protein comes from plant (such as beans, lentils, nuts, seeds, and whole grains) and animal (such as meat and dairy) sources. Your doctor will be able to give you an exact amount in grams that you should not exceed daily.
Foods to Avoid
There are some foods your doctor may recommend that you avoid entirely on a kidney-protecting diet. These are essentially foods that are high in potassium, phosphorus, and sodium. This list is not inclusive of all the foods high in these nutrients, so it’s best to ask your doctor which foods you can and cannot eat. Make a list and keep copies at home and with you to use at the grocery store or when you’re eating out.
Foods high in potassium include dairy, such as milk, cheese, and sour cream. They also include grains like brown rice and anything heavy in bran, like dark breads. Potatoes and fruits like tomatoes, avocadoes, melons, and bananas are also high in potassium.
To avoid foods high in phosphorus, again you’ll potentially need to avoid some dairy products, most nuts, and a variety of grains. These grains include oatmeal, granola, bran cereals, and dark, whole-grain breads. Many sodas also include phosphorus, so keep this in mind before you crack open a cold can. Some sodas are phosphorus-free, such as diet versions of Sprite, ginger ale, and orange soda. Be sure to check every brand in case of changes.
Your doctor can tell you how much sodium you should aim to consume per day. While everyone needs sodium to survive, your doctor may want you to consume 1,500 mg a day or less. You can use herbs to flavor your foods or opt for sodium-free seasonings. Some items at the grocery store will be specifically labeled as “low-sodium”; look for these while you shop.
While changing to a kidney-friendly diet can involve several steps, it’s possible to do so successfully. Monitoring and limiting your potassium, phosphorus, protein, and sodium will likely be essential. The key is to find a healthy balance of incorporating these nutrients into your diet in amounts that won’t limit kidney function.