How to Manage Kidney Disease with a Plant-Based Diet
Did you know that renal (or kidney) disease can be managed with a plant-based diet? Not so long ago, people suffering from kidney disease shunned a lot of plant foods, because of the special nutritional considerations related to this diet regimen. But new research shows that eating a more plant-based diet can help improve nutritional profile, reduce inflammation, and prevent disease development later on. So, how can you take advantage of this new information to harness the power of plants while you manage renal disease?
I’m answering all of those questions today on the blog, thanks to our in-depth interview with renal nutrition expert Deborah Clegg, PhD. She dives into the latest science on how you can eat to preserve kidney function while promoting optimal health, so that you can enjoy a more vibrant, healthful life. We are so lucky to have her answer some of our top questions.
How to Manage Kidney Disease with a Plant-Based Diet
Sharon: What is the cause of renal disease, and how is diet an important part of the disease?
Clegg: Kidneys filter extra water and wastes out of the blood and make urine. Kidney (or renal) disease means your kidneys are damaged and can’t filter blood the way they should. In the United States, the two leading causes of kidney failure or chronic kidney disease (CKD) are diabetes (also called Type 2, or adult onset diabetes) and high blood pressure. When these two diseases are controlled by treatment, the associated CKD can often be prevented or slowed down. Diet is an important part of living well with CKD. As CKD progresses, your dietary needs change and should be controlled and monitored. For example:
- Diabetes: People with diabetes should be tested for kidney disease every year and should control their blood sugar and blood pressure. Blood sugar can be controlled by selecting appropriate foods that are not high in sugar and by eating a heart-healthy diet that contains vegetables and high fiber foods.
- Blood pressure: People with elevated blood pressure should eat a diet that is low in sodium (a part of salt) and high in fruits and vegetables. Your diet should contain less than 2,300 milligrams of sodium each day. Buy fresh foods often to reduce sodium intake, as many prepared or packaged foods have added sodium. Use spices, herbs, and sodium-free seasonings in place of salt. Check for sodium on the Nutrition Facts label of food packages. A Daily Value of 20 percent or more means the food is high in sodium. Rinse canned vegetables, beans, meats, and fish with water before eating.
Sharon: What does the latest research show about the health benefits of eating a plant-based diet for managing CKD?
Clegg: For the general adult population, a diet rich in fruits and vegetables, whole grains and plant-based protein is considered a healthy and nutritious diet. Plant-based diets are high in nutrients such as potassium, and potassium-rich foods are considered healthy due to their alkalinity, high micronutrient (vitamin and mineral, including potassium) and fiber content, and phytochemical content that further benefit the human body. Conversely, the dietary requirements for chronic kidney disease (CKD) patients is restrictive and looks different than the accepted healthy diet for the adult population. The potassium that has many benefits for the general population can be fatal for people with CKD if the level of potassium in their blood spikes, a condition known as hyperkalemia. In the United States alone, there are more than three million people who are living with hyperkalemia.
Because of the risk of hyperkalemia in CKD patients, they are advised to limit their potassium intake due to the deleterious effects of hyperkalemia, most notably, cardiac arrhythmia, including sudden death. However, this puts CKD patients at risk for lacking essential vitamins and minerals normally found in potassium-rich food sources. Newer research suggests the health benefits of a plant-based diet outweigh the determents in some CKD patients. For those at risk of hyperkalemia, the availability of treatment options such as potassium binders may facilitate the balance of potassium in the body, while also maximizing the benefit of a plant-based diet.
Sharon: How can a plant-based diet pattern help manage or treat chronic kidney disease?
Clegg: By liberalizing the diet to allow for more plant-based foods consisting of an increase in fruit, vegetables, and fiber, the CKD patient could benefit from improved nutrition, ideally leading to the reduction in disease development and/or complications, most notably, atherosclerosis, which occurs when fatty deposits clogs the arteries.
Sharon: In the past, people living with CKD had to reduce levels of nutrients, such as potassium, which are healthful for people without this condition. A healthy, plant-based diet is high in potassium. How does this work out in the overall eating plan?
Clegg: Problems can occur when blood potassium levels are too high or too low. Damaged kidneys allow potassium to build up in the blood, which can cause serious heart problems.
What has been underappreciated is that meat is also a source of potassium. Plant-based foods are typically higher in carbohydrates and it is well known that insulin facilitates potassium homeostasis – therefore, in foods that contain carbohydrates which would stimulate insulin release, it is possible that these foods do not cause the same overall rise in potassium that foods that are low in carbohydrates, such as meats, would cause.
Newly accumulating data suggest that even people with CKD who eat diets that are plant-based and higher in potassium do not have the rise in serum potassium that was once thought. Of course, this is done on an individual basis and within the close monitoring of the physician and dietitian, but this evidence, as well as the availability of treatments such as potassium binders which rid the body of excess potassium, liberalizes the CKD diet to include plant-based foods in order for these patients to enjoy the associated health benefits.
Sharon: What about vegan and vegetarian diets—might these be good approaches for people living with CKD? Why?
Clegg: Previously, there were concerns associated with recommending a more plant-based diet for CKD patients because there were fears that this diet would fall short of the required amount of protein and could potentially result in malnutrition leading to protein energy wasting. Interestingly, vegetarian CKD patients have lower inflammation which may explain how patients following a vegetarian diet maintain their protein levels, possibly indicating that protein stores can be sustained in vegetarians. Furthermore, a diet higher in fruits, vegetables and plant protein, and lower in animal protein, would lend itself to be more alkaline while still obtaining the necessary amount of protein.
Sharon: What are the foods and nutrients in a plant-based diet that might be protective?
Clegg: Plant-based diets contain foods that are high in potassium and are considered healthy due to their alkalinity, high micronutrient and fiber content, and phytochemical content that further benefit the human body. Studies have demonstrated a reduction in blood pressure when potassium consumption increases and sodium consumption decreases in the healthy adult population, while an insufficient intake of potassium increases the risk of cardiovascular disease and stroke. Additionally, potassium intake has been associated with reduced risk of kidney stones and increased bone mineral density.
Certain potassium containing foods, including nuts, legumes, beans, and dairy products also contain phosphorus, which can be bad for your kidneys. However, the phosphorus in foods from plants is less well absorbed than the phosphorus found in meat-based and processed foods, so while eating a plant-based diet is higher in phosphorus, it results in lower phosphorus levels.
Sharon: What tips can you provide for people living with CKD who want to try a plant-based diet? How can they tailor this diet to meet their specific needs?
Clegg: In the general population, increased consumption of fruit and vegetable intake has been shown to reduce the risk for coronary heart disease, Alzheimer’s Disease, cancer, diabetes, cataracts, age-related degeneration, and cardiovascular disease. By liberalizing the diet to allow for a more plant-based diet consisting of an increase in fruit, vegetables, and fiber, the CKD patient could benefit from the improved nutritional profile of their diet, ideally leading to the reduction in disease development and/or complications. A reduction in cardiovascular disease is of the upmost importance in CKD patients as it is the primary cause of death. Certain micronutrients, including vitamin C and carotenoids, as well as fiber, can help protect against the development of this deadly disease, however these have been shown to be poorly consumed in CKD patients.
A disconnect exists between the restrictions of the CKD diet and what is recommended for a heart healthy diet. An individualized method to dietary restrictions consisting of a more balanced diet, and when needed, treatment to help lower the risk of high potassium, should be implemented. A liberalized diet will lead to better compliance and overall improved health. Working with the physician and dietitian to begin to incorporate plant-based foods with frequent monitoring of potassium is an excellent place to begin.
For more information on managing high potassium, please visit kidney.org.
Disclosure: Some of Deborah Clegg’s research in plant-based diets and hyperkalemia has been supported by Relypsa, Inc. (a Vifor Pharma Group company).
About Deborah Clegg, PhD
Deborah Clegg, PhD is a known expert in the field of sex hormones and metabolism with a specific interest in nutrition and how it interacts with physiology. She has authored over 150 articles in impactful journals such as The New England Journal of Medicine, JAMA, American Journal of Physiology, and the National Kidney Foundation. She is a clinical dietitian and in this role, she has advocated for personalized nutritional approaches and liberalization of diets to enhance patient compliance and satisfaction. Deborah is a Distinguished Visiting Professor at American University and holds faculty appointments in the role of Professor at Cedars-Sinai Medical Center and the University of California Los Angeles (UCLA). Deborah and her research has been featured in many forms of media, to include the television program The View, and HBO series entitled ‘Weight of the Nation’, as well as in the popular press to include magazines such as Vogue, Mademoiselle, Ladies Home Journal, and Nature.
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