Arti Parpia | University of Ontario - Institute of Technology
Liberalization of Hemodialysis Dietary Restrictions: Evaluating Safety, Acceptability and Nutritional Impact
Co-applicant(s): JoAnne Arcand, Ron Wald
Lay Abstract
Background: People with end-stage kidney disease (ESKD) rely on hemodialysis (HD) to survive. While HD is life-saving, it comes with strict dietary rules to reduce the risks from high levels of potassium and phosphorus in the blood. Patients are often told to avoid foods high in potassium and phosphorus, such as fruits, vegetables, legumes, nuts, and dairy. Following the HD diet can be stressful, reduce enjoyment of meals, and make it difficult to eat a healthy diet. Evidence shows that restricting dietary sources of potassium and phosphorus has only small effects on the potassium and phosphate in the blood. Current guidelines may focus too much on restriction, leaving patients with diets that are hard to follow and not always nutritionally complete. This can affect overall health, quality of life, and adherence to the diet. There is an urgent need to explore whether a more flexible, patient-centered approach could improve diet quality, patient satisfaction, and overall well-being.
Purpose: Our research aims to find out whether more liberal approaches to potassium and phosphorus in the HD diet can be safe, effective, and easier for patients to follow. We want to see if patients can enjoy more nutrient-rich foods without putting their health at risk. By understanding how liberalized diets affect blood chemistry, nutrition, and quality of life, we hope to guide dietary advice that supports both health outcomes and daily life. Our goal is to improve the experience of living with HD, helping patients feel better and eat well.
Methods: We are conducting two related studies. The first is an initial trial at dialysis centers across Canada, involving 148 adults on HD with higher-than-normal potassium levels. Participants are randomly assigned to one of two different diets for six months. One group receives a modified potassium diet that encourages minimally processed foods, cooking techniques to reduce potassium, constipation prevention, and avoiding potassium additives. The other group receives standard low-potassium education that emphasizes avoiding high-potassium fruit, vegetables, juices and grains. Support and guidance will be provided by monthly sessions with dietitians. We will monitor blood potassium levels, severe high-potassium events, dietary intake, and patient satisfaction. The second study, PHOSPHATE-DIET, is part of a larger trial examining phosphate management in HD patients. High blood phosphate can contribute to heart problems, but it is unclear whether strict lowering improves health. PHOSPHATE-DIET examines how intensive versus more liberal approaches to phosphate affect diet, nutrition, and quality of life in 122 patients across Canada. Patients complete dietary recalls and questionnaires about their diet and nutrition-related quality of life. We will compare groups to see whether strict phosphate targets affect diet quality, nutrient intake, and the enjoyment of food.
Anticipated Outcomes: We expect to show that more liberalized potassium and phosphate strategies are safe and can improve diet quality, nutritional intake, and patient satisfaction. Findings may show that patients can enjoy a wider variety of nutrient-rich foods without harmful effects on blood chemistry. This could support simpler, more patient-centered dietary guidance for people on HD.
Patient Engagement: Patient partners help us focus on real-world challenges, making our research relevant and meaningful to those living with HD.
Relevance to Patients/Community: This work directly addresses the daily challenges faced by HD patients. By showing that dietary restrictions can be safely relaxed in some cases, we hope to improve patients’ quality of life, reduce stress around eating, and support better nutrition. Our findings will help healthcare providers give practical advice that is easier to follow and more aligned with patients’ preferences.
Conclusion: Our research seeks to change how we approach diet in HD, moving from strict restrictions to evidence-based, patient-centered guidance. By understanding how liberalized potassium and phosphate strategies affect health and quality of life, we aim to make HD diets safer, simpler, and more enjoyable. Ultimately, this work could improve the daily lives of thousands of patients living with ESKD, helping them eat well, feel better, and thrive while on hemodialysis.