Plant-based diets may be a helpful strategy for patients on dialysis to lower their phosphorous levels, according to a speaker at the virtual Annual Dialysis Conference.

Shivam Joshi

“Plant-based diets have historically been avoided or neglected in the use of our patients with kidney disease, especially those on dialysis, for a variety of reasons including issues related to potassium and inadequate protein,” Shivam Joshi, MD, a clinical assistant professor of medicine at Bellevue Hospital and NYU Grossman School of Medicine, said. “However, recent research suggests this risk may be overstated.”

According to Joshi, plant-based diets can include a flexible diet that doesn’t cut out all animal products, but limits intake compared to the standard American diet. Therefore, Joshi said, it is possible to eat a plant-based diet on dialysis and consume enough protein. Similarly, the risk of consuming too much protein is unlikely since plant-based phosphate is mostly bound as phytates which means it is not absorbable.

“It’s possible to take any diet and make it unhealthy or inadequate,” Joshi said.

Joshi referenced a study that showed plant-based foods that report high potassium levels are often juices, sauces and dried fruits but not unprocessed plant-based foods. Factors that can reduce an increase in serum potassium in patients with end-stage kidney disease who follow a plant-based diet include fiber, colonic secretion of potassium, intracellular movement of potassium and bioavailability.

Another study Joshi referenced compared serum phosphate levels among vegetarian and non-vegetarian patients with ESKD. The results showed vegetarian patients recorded significantly lower serum phosphate levels.

“Maintaining protein while reducing phosphorus may be achieved through a plant-based diet due to the low bioavailability of these foods, especially if they’re unprocessed the low phosphomimic index of these foods. Plant-based diets may provide lower protein compared to animal-based diets or the standard American diet, but overall, they have not been shown to affect nutrition or to have caused a deficiency. Potassium levels do not appear to increase within those consuming a plant-based diet on dialysis,” Joshi said. “More research is certainly needed.”