The #1 Worst Food for Your Kidneys, According to Nephrologists—and What To Eat Instead
Kidney health isn’t something that’s front of mind for most people (unless there’s a serious health problem going on), but considering that it’s literally impossible to live without them unless you're on dialysis, it’s worth it to make sure you’re living in a way that keeps them healthy.
The kidneys are responsible for regulating water balance in the body. They help the body keep enough water to function while releasing excess water to be eliminated through urination. The kidneys also produce two hormones. One helps regulate red blood cells while the other hormone is the active form of vitamin D and helps regulate calcium.
As with every other part of the body, what we eat and drink greatly impacts kidney health—for better or for worse. Curious as to how? Here, nephrologists explain the connection between diet and kidney health and reveal the one common type of food that damages the organs the most.
Related: The Common Habit That Could Be Damaging Your Kidneys, According to a Nephrologist
General Tips for Eating for Kidney Health
Here’s the good news about eating for kidney health: The best foods for your kidneys are the exact same ones that benefit the rest of the body. Dr. Cynthia Silva, MD, a nephrologist and the Vice President of Clinical Affairs of Outset Medical, says it’s important to eat a well-balanced diet (prioritizing nutrient-rich foods like vegetables, fruit, whole grains and plant proteins) and to stay well-hydrated.
Nephrologist Dr. Alice Chedid, MD, says that it’s important to manage blood sugar levels too—particularly if you are diabetic. “Diabetes is the leading cause of chronic kidney disease. Maintaining a healthy diet that is not high in sugar will help reduce the risk of worsening kidney function,” she says.
Related: 11 Things You Didn't Know About Your Kidneys
It’s also important to drink plenty of water. (Aim for eight 8-ounce glasses of water a day.) “It is crucial to stay hydrated, especially in the hot summer weather, so you don't produce concentrated urine. This increases the risk of forming kidney stones,” Dr. Chedid says.
If you are currently experiencing kidney problems, Dr. Silva says your diet may have to change, based on recommendations from your doctor: “People with kidney disease may need to control their amounts of protein, sodium, potassium, phosphorus and calcium." Dr. Chedid agrees, saying that people with kidney disease should be especially mindful of how much protein they’re eating—minimizing animal proteins in particular. “Eating food high in protein will make kidneys work harder and can worsen the kidney disease with time,” she explains.
Dr. Silva adds that having another type of health issue, like diabetes or a heart condition, may require specific diet recommendations as well. “Patients with these conditions should speak with their doctor about working with a registered dietician who can help them make the right food choices,” she says.
Related: 7 Tricks to Tame Your Blood Pressure Quickly
The Worst Food for Kidneys, According to a Nephrologist
There’s one type of food in particular that the nephrologists say is especially detrimental for kidney health: foods high in salt, such as chips, cold cuts and cured meats, and ultra-processed frozen foods like pizza, burritos and TV dinners. Dr. Emily Chang, MD, a nephrologist and associate professor of medicine at the University of Chapel Hill School of Medicine, explains that this is because the two biggest risk factors for kidney disease are diabetes and high blood pressure, and eating a diet high in salty foods can up the risk for both conditions. To her point, scientific research shows that people with diabetes and hypertension are 50 percent more likely to be diagnosed with kidney disease.
“Eating foods high in salt puts pressure on the kidneys because the kidneys have a lot of blood vessels,” Dr. Chang explains. “When blood pressure is high, that’s pressure in your blood vessels, which translates to pressure in the kidneys.” She says that over time, this can cause scarring and kidney disease.
Dr. Silva agrees that salty, ultra-processed foods are the absolute worst for kidney health. “When we eat foods that are processed, meaning packaged, canned or frozen, they [can] contain large amounts of hidden preservatives like sodium, sugar and fat, which help extend the shelf life of the food and make it taste better since it is not fresh. This decreases the nutritious value of the food, like less fiber, while increasing calories,” she says. “All together, this puts enormous strain on the kidneys to filter out these excess preservatives while maintaining all the other essential functions they perform daily.”
If you want to cut down on your salt intake, Dr. Chedid recommends cooking at home more and using herbs to add flavor, such as garlic, basil, rosemary and mint. Unlike salt, which negatively impacts kidneys when consumed in excess, these herbs benefit the body because they’re high in antioxidants, which help prevent or lower chronic inflammation.
Even if you’ve been eating a diet high in ultra-processed foods for decades, it’s not too late to make a change. But if you already have late-stage kidney disease, Dr. Chang says changing your diet won’t be enough to make a significant difference. That’s why it’s important to have healthy eating habits in place before your health is negatively impacted. If your kidneys are in top shape, you want to keep it that way—and that starts with having a healthy diet in place.
Next up, check out this list of 25 foods that can help prevent or lower high blood pressure.
Sources
Dr. Cynthia Silva, MD, nephrologist and the Vice President of Clinical Affairs of Outset Medical
Dr. Alice Chedid, MD, a nephrologist at University Clinical Health
Dr. Emily Chang, MD, nephrologist and associate professor of medicine at the University of Chapel Hill School of Medicine