Nutritional Status, Hyperkalaemia and Attainment of Energy/Protein Intake Targets in Haemodialysis Patients Following Plant-Based Diets

A Longitudinal Cohort Study

Ailema González-Ortiz; Hong Xu; Samuel Ramos-Acevedo; Carla M. Avesani; Bengt Lindholm; Ricardo Correa-Rotter; Ángeles Espinosa-Cuevas; Juan Jesús Carrero


Nephrol Dial Transplant. 2021;36(4):681-688. 

In This Article

Abstract and Introduction


Background: Patients undergoing haemodialysis (HD) are often discouraged from eating fruits and vegetables because of fears of hyperkalaemia and undernutrition, yet evidence to support these claims is scarce. We here explore the association between adherence to a healthy plant-based diet with serum potassium, surrogates of nutritional status and attainment of energy/protein intake targets in HD patients.

Methods: We performed an observational single-centre study of stable patients undergoing HD with repeated dietary assessment every 3 months. Patients were provided with personalized nutritional counselling according to current guidelines. The diet was evaluated by 3-day food records and characterized by a healthy plant-based diet score (HPDS), which scores positively the intake of plant foods and negatively animal foods and sugar. The malnutrition inflammation score (MIS) and serum potassium were also assessed at each visit. We used mixed-effects models to evaluate the association of the HPDS with markers of nutritional status, serum potassium levels and attainment of energy/protein intake targets.

Results: After applying inclusion and exclusion criteria, a total of 150 patients contributing to 470 trimestral observations were included. Their mean age was 42 years [standard deviation (SD) 18] and 59% were women. In multivariable models, a higher HPDS was not associated with serum potassium levels or odds of hyperkalaemia {potassium >5.5 mEq/L; odds ratio [OR] 1.00 [95% confidence interval (CI) 0.94–1.07] per HPDS unit higher}. Patients with a higher HPDS did not differ in terms of energy intake [OR for consuming <30 kcal/kg day 1.05 (95% CI 0.97–1.13)] but were at risk of low protein intake [OR for consuming <1.1 g of protein/kg/day 1.11 (95% CI 1.04–1.19)]. A higher HPDS was associated with a lower MIS, indicating better nutritional status.

Conclusions: In patients undergoing HD, adherence to a healthy plant-based diet was not associated with serum potassium, hyperkalaemia or differences in energy intake. Although these patients were less likely to reach daily protein intake targets, they appeared to associate with better nutritional status over time.


People with chronic kidney disease undergoing maintenance haemodialysis (HD) are advised to change their diet in order to avoid complications linked to their inability to excrete and metabolize some specific nutrients. These recommendations involve restrictions of phosphorus, potassium, sodium and fluid intake, while providing sufficient energy and protein intake to prevent undernutrition.[1–3] Adherence to these recommendations typically results in a low intake of plant foods,[4–6] and in a recent survey of ~8000 prevalent patients on HD from Europe, only 4% reached the minimum recommended consumption of four or more daily servings of fruits and vegetables for healthy eating.[7] The main reason for discouraging the intake of fruits and vegetables in these patients traditionally involves fears for hyperkalaemia due to dietary potassium load and for undernutrition, as plant-protein has been judged to have low biological value.[8] However, evidence to support these claims is scarce and graded as expert opinion recommendations.[9,10] Recent studies indicate instead that such well-meaning guidance may deprive HD patients of potential benefits from consuming plant foods; for instance, observational studies suggest that while serum potassium in dialysis patients correlates poorly with dietary estimations of potassium intake,[11,12] higher fibre intake is associated with less constipation, resulting in lower intestinal potassium absorption[13] with less inflammation, less myocardial hypertrophy and injury and lower risk of cardiovascular events,[14] and that increased consumption of fruits and vegetables associates with lower risk of death.[7] The term plant-based diet refers to a diverse family of dietary patterns generally characterized by a higher frequency of consumption of plant foods and minimal to no consumption of animal foods.[15] These diets are usually lower in fat and animal protein and higher in fibre and plant protein.[16] Plant-based diets are currently gaining popularity in society and may be preferred by many patients on dialysis, especially if transitioning from a plant-based low-protein diet during their pre-dialysis care.[17] However, there is virtually no information on the risks and benefits of adhering to such diets in this population. In this study, we explore the likelihood of undernutrition and hyperkalaemia among routine-care patients on HD adhering to a plant-based dietary pattern.