Walnuts are generally beneficial for your health. They are high in omega-3 fatty acids which improve memory, improve heart health, and boost brain power, say the experts at UC Davis Health. Eating walnuts also encourages healthy gut bacteria and may even prevent certain cancers.
However, consuming walnuts can be dangerous for people who have kidney disease. According to Parade, individuals with advanced-stage chronic kidney disease (CKD), as well as those on dialysis, need to limit or avoid walnuts.
Walnuts contain phosphorus and potassium, which can be toxic if consumed in large amounts. People with CKD can't process these nutrients well and run the risk of having excessively high levels in their bodies.
Also, walnuts and almonds contain oxalates which can cause kidney stones if eaten in large amounts, warns Dr. Jennie Stanford, a family physician and obesity expert.
"CKD patients should pay attention to their diet to help control their disease," she says.
Stanford recommends limiting other foods that are high in potassium such as bananas, citrus fruits, spinach, avocados, and tomatoes. She also recommends avoiding foods high in phosphorus such as dark-colored sodas, organ meats, and dairy products. Since diabetes and high blood pressure can lead to CKD, it's also important to be careful with sodium intake to promote healthy blood pressure.
While walnuts contain many beneficial nutrients, people with advanced kidney disease are better off seeking those nutrients from other sources such as berries, apples, grapes, bell peppers, fatty fish, flaxseed, and chia seeds. These all contain polyphenols, antioxidants, or omega-3 fatty acids that boost health in a similar way to walnuts.
The best advice for patients with kidney disease is to check with their healthcare providers to evaluate if eating walnuts is risky for their health and to establish a personalized diet plan to improve their overall health and control CDK.