Kidney Disease Diet: 8 Foods That May Be Beneficial

If you have chronic kidney disease (CKD)—when the kidneys can't filter blood due to damage, according to the Centers for Disease Control and Prevention (CDC)—one of the most important things you'll do is meet with a renal nutritionist, aka a nutritionist who specializes in kidney function.

Chronic Kidney Disease Diet

"At first, a kidney-friendly diet can seem overwhelming to my patients with CKD, but over time, it becomes something that's much more manageable," said Melissa Ann Prest, DCN, RDN, a renal nutritionist in Chicago and a spokesperson for the Academy of Nutrition and Dietetics.

Certain foods—even fruits and veggies—may have to be restricted or even off limits when you have kidney disease.

Your dietary restrictions depend on what stage of kidney disease you're at, said Prest. "In the early stages, it's all about following an overall healthy low-sodium diet, especially if you have other conditions like type 2 diabetes or high blood pressure," said Prest. "But as the disease progresses, you'll find that you also need to start restricting protein, as well as foods high in the minerals potassium and phosphorus."

Here are eight foods that are good to include as part of your regular diet, no matter your stage of CKD.

Spices

All patients with CKD need to watch their salt intake. "When your kidneys are damaged, they can't control how much sodium is in your body, which can cause your blood pressure to rise," said Staci Leisman, MD, a kidney specialist at Mount Sinai Hospital. This, in turn, worsens kidney damage and also raises your risk of heart disease, according to the CDC.

If you have kidney disease, it's very important that you follow the recommendation of the Dietary Guidelines for Americans and consume under 2,300 milligrams a day. People in the later stages of kidney disease may need to go even lower, added Dr. Leisman.

One great way to slash sodium from your diet is to reach for your spice rack instead of the salt shaker, said Erin Rossi, RD, a nutritionist specializing in kidney disease at the Cleveland Clinic.

Spices like basil, curry, dill, ginger, and rosemary can add flavor to any dish, whether it's meat or a vegetable. The National Kidney Foundation (NKF) suggests that you purchase spices in small amounts because they lose flavor over time. The NKF also suggests adding ground spices to foods about 15 minutes before you finish cooking them and adding whole spices to food at least one hour before. If you're using fresh herbs, combine them with oil or butter, let them sit for 30 minutes, then brush them on meat or veggies as they cook.

While you may be tempted to use a salt substitute, Rossi didn't recommend it. "They often contain potassium, which many patients, particularly those with late-stage disease, need to limit," Rossi said.

Berries

There's no doubt that all types of berries are nutritional powerhouses: They're rich in heart-healthy antioxidants, including vitamin C, according to the Academy of Nutrition and Dietetics. But they also have another benefit: they're low in potassium. "When people get into very late-stage kidney disease, certain foods, even nutritious ones like fruits and vegetables, can increase the potassium in your blood to a dangerous level," said Prest. This can cause symptoms like weakness, numbness, and tingling or even trigger heart palpitations, according to the NKF.

Fruits higher in potassium include bananas, avocados, melons, oranges, spinach, and raisins, according to the Harvard School of Public Health. But always check with your nutritionist before cutting out those foods, said Prest. "If your potassium levels are normal, then there's no reason why you can't safely eat these fruits, which are all good for you."

Fruits that are low in potassium include apples, cherries, peaches, plums, pears, and grapes, according to the NFK.

"We're more concerned about patients avoiding processed foods that have phosphorous added to them to make them shelf stable, like pancake mixes, chicken patties, and macaroni and cheese," said Prest. So what should you look for when you're shopping? The NKF suggested checking labels for additives that include "phos," for example:

• Dicalcium phosphate
• Disodium phosphate
• Monosodium phosphate
• Phosphoric acid

Eggs

People with kidney disease need to limit the amount of protein they eat. "Having too much protein can cause waste to build up in your blood, and your kidneys may not be able to remove all the extra waste," explained Rossi. But you still need enough protein to maintain muscle mass and help your body fight off infection.

"When it comes to protein, it's also not just about how much you eat—it's about eating higher quality proteins," Rossi said.

Eggs are a particularly good source of protein because they're also low in phosphorus, which is another mineral you need to limit when you have chronic kidney disease, Rossi said.

"When your kidneys are not working well, phosphorus builds up in your blood, which can leach calcium from your bones and raise your risk of developing osteoporosis," Rossi said. While foods like nuts, seeds, peanut butter, and beans are all good sources of protein and part of a heart-healthy diet, they're also high in phosphorus. Talk to your dietitian about how much of these foods you can safely eat.

Olive Oil

A kidney-friendly diet should be low in saturated fat, which raises your risk of heart disease, said Rossi. That makes healthy fats like olive oil the best choice for cooking and baking, and you can also use it in place of high-fat salad dressings, Rossi said.

A Mediterranean-style diet—an eating pattern rich in fruits, veggies, fish, and heart-healthy fats like olive oil—is linked to a 50% reduced risk of developing chronic kidney disease, according to a 2014 study published in the Clinical Journal of the American Society of Nephrology. It's also sodium-, potassium-, and phosphate-free, making it an excellent choice for people with kidney disease.

Cruciferous Vegetables

Got a craving for potassium-rich potatoes? Munch on mashed cauliflower instead. It's high in fiber but low in both potassium and phosphorus, making it a healthy choice for people with kidney disease, said Prest.

Some tasty ways to eat it: puree it as a cream sauce, mash it into a pizza crust, grate it into a substitute for rice or pickle it for a low-calorie salty, crunchy, satisfying snack. Other cruciferous veggies, like cabbage or kale, are good choices too. Broccoli is also fine, but eat it raw, as cooked broccoli contains more potassium, according to the NKF.

If you want to keep high potassium veggies like potatoes, sweet potatoes, carrots, beets, and winter squash in your diet, you can leach them to pull some of the potassium out, according to the NKF. Slice them 1/8-inch thick, rinse them, and then soak them for at least two hours in warm water using a 10-to-1 water-to-veggie ratio. Then cook them with five times the amount of water to the number of vegetables.

Water

You may have heard that you need to restrict fluid intake if you have kidney disease, but that's really only true in the late stages of the disease when you require dialysis, according to the NKF. "If you're not at that point, and you don't have swelling in your legs, feet, or ankles, or around your eyes, it's usually not necessary," said Prest.

Water itself helps your kidneys remove wastes from your blood and helps keep your blood vessels open so that blood reaches your kidneys, according to the NKF. If you're parched, it's harder for this delivery system to work and can even lead to more kidney damage. It also reduces your chance of developing kidney stones or urinary tract infections, both of which can harm the kidneys.

If you're in the later stages of kidney disease, your doctor may tell you to limit all fluids, including water. The first step is to cut back on foods that contain a lot of water, like soup, ice, and gelatin, as well as certain fruits and veggies, said Prest. The NKF stated that most dialysis patients would have to cap fluid consumption at about 32 ounces a day.

Refined Grains

You don't have to shun white bread, pasta, rice, and other refined grains. In fact, these foods may be beneficial for people with very advanced CKD who need to limit their phosphorus and/or potassium content, according to the NKF. It turns out that the more bran and whole grains in bread, the higher their phosphorus and potassium content.

"Whole grain products are higher in phosphorus and potassium, so they need to be limited if you have kidney disease," said Rossi. Just don't overdo it on the starchy stuff, as they can cause you to gain weight and raise the risk of developing type 2 diabetes—the leading cause of kidney disease, according to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).

Garlic and Onions

Garlic and onions are great options for seasoning food if you have chronic kidney disease since they provide a robust, savory flavor that will prevent you from reaching for the salt shaker or seasonings with added phosphorus, said Prest.

They also may be protective against CKD. Why? They contain allicin, a substance that appears to lower blood pressure and improve kidney dysfunction. A 2017 study published in the International Journal of Molecular Science found that high doses of allicin were just as effective as the high blood pressure and kidney disease drug losartan. A 2016 study in Oxidative Medicine and Cellular Longevity concluded that allicin could help reduce high blood pressure in people with CKD.

Summary

There are a variety of options available to maintain a healthy diet for someone with chronic kidney disease. By limiting your salt intake, you can incorporate garlic, onion, and spices to add flavoring to your food. You can eat refined grains, certain fruits, eggs, and cruciferous vegetables. And you'll want to stay hydrated—except if you are in late-stage kidney disease.

Maintaining a healthy kidney diet can be difficult. Before making any significant changes to your diet, consult a dietician to make sure those changes are best for you.