One in every seven U.S. adults has chronic kidney disease (CKD), which occurs when your kidneys can no longer filter waste or fluid effectively.
In addition to treating conditions that may contribute to CKD, such as diabetes, high blood pressure, or heart disease, what you eat can play a key role in managing CKD.
Making the right dietary changes can slow the progression of CKD and delay the need to start dialysis or get a kidney transplant.
Choosing certain foods over others also can help regulate abnormalities in electrolyte nutrients and reduce CKD-related swelling, says Chicago-based registered dietitian Melanie Betz, RD, who specializes in kidney health and nutrition. The healthiest ingredients are often found in diets that are plant-forward, such as the Mediterranean diet or Dietary Approaches to Stop Hypertension (DASH) diet, she says.
Similarly, limiting some foods and beverages that are high in potassium, phosphorus, and sodium can keep CKD from getting worse. Your precise dietary needs will differ depending on the status of your kidneys. Although there are some common dietary elements that you may want to avoid if you have CKD, it’s wise to ask your doctor about what works best for your situation so you can get the nutrients you need.
1. Salami
Salami, a processed meat in the same family as bacon, sausage, and other deli meats, is a triple whammy, Betz says. One, these foods are high in sodium. Because your kidneys remove sodium from the body, experts recommend limiting it.
Two, these foods are often high in saturated fat, which can increase your risk of cardiovascular disease when you have CKD.
And three, animal proteins can have a negative impact on kidney function, Betz says.
2. Soda
Soda has a ton of added sugars and includes almost no nutritional value. This sugar itself does not damage the kidneys, but about 1 in 3 adults with diabetes also has CKD, and too much sugar can increase the risk of kidney issues for people with diabetes.
Soda and other sweetened beverages, including fruit, sports, and energy drinks, are a top source of added sugars in our diet and may be a good target if you’re looking to reduce your sugar intake.
3. Starfruit
This is one fruit that experts say is off limits. Starfruit, a tropical fruit, contains neurotoxins that can build up and harm the brain, leading to confusion and even seizures or death in the most serious cases.
This is not a problem for folks who have kidneys that function normally. But if you have CKD, your body cannot effectively filter out a toxin called caramboxin, which is why you can get sick. Another toxin in the starfruit, calcium oxalate, is believed to be toxic to the kidneys.
For your fruit fix, stick to berries, apples, or melons.
4. Potato Chips
Ultraprocessed foods like potato chips contain added sugar, salt, colorings, flavorings, stabilizers, and other ingredients to make them readily shelf-stable. It’s not just chips. Other unhealthy options include packaged cookies, muffins, breads, cupcakes, cakes, and snack mixes.
“These foods don’t provide a lot of health benefits or nutrition,” Betz says.
In addition to containing ingredients that can worsen kidney disease, these foods also can increase your risk of getting CKD. People who eat a lot of ultraprocessed foods are 24 percent more likely to develop CKD than those who eat smaller amounts of them.
5. Fast Food Meals
Often considered ultraprocessed foods, fast-food products may be high in sodium, saturated fat, and sugar.
These meals can contribute to unhealthy blood pressure, blood sugar, and cholesterol levels, all of which are a strain for your heart.
If you have CKD, you are at greater risk of heart disease. Reducing foods such as this could help you stem off the inflammation and other factors that increase this risk.
6. American Cheese
Dairy foods are often high in phosphorus, Betz says.
When you have CKD, your kidneys cannot remove excess phosphorus effectively. High phosphorus levels in your blood also can weaken bones and raise your risk of heart disease.
Heavily processed cheese, such as American, also may include added phosphorus. If cheese is acceptable in your diet, based on your stage of CKD and other health factors, less-processed cheese such as cream cheese and fresh gouda may provide probiotics and healthy amounts of calcium and various vitamins.
When scoping out the phosphorus content in foods, be on the lookout for ingredients that include:
- Phosphoric acid
- Calcium phosphate
- Monopotassium phosphate
- Disodium phosphate
- Sodium acid pyrophosphate
- Sodium tripolyphosphate
7. Frozen Pizzas
These ultraprocessed foods often contain amounts of phosphorus and potassium that may worsen your CKD, Betz says. Your kidneys excrete potassium, like phosphorus, and CKD can make that more difficult.
Foods such as fruits and vegetables that are rich in potassium can help control blood glucose and acid levels, Betz says, which is a good thing. But when these minerals are added to pre-made meals or frozen pizzas during processing, our bodies absorb most of them, creating potential problems.
Too much potassium for people who have CKD can cause hyperkalemia. Speak with your doctor or registered dietitian to find out how much potassium you should consume.
Some packaged dinners also may include an unhealthy amount of sodium.
“It’s important to label-read because this is so individualized per product,” Betz says.
The Takeaway
- Your diet can play a big role in managing chronic kidney disease.
- Foods and beverages that are high in added sugar, sodium, and saturated fat can promote kidney disease and increase risks of other health issues.
- Plant-forward diets and minimally-processed ingredients could be helpful in managing CKD.