A Balanced Vegetarian Diet for Kidney Patients
Less than five percent of end stage renal disease (ESRD) patients are vegetarian, according to our estimates. This includes patients who follow vegetarianism because of their religious, cultural, social and personal beliefs and those patients who are suffering from taste changes due to uremia as a result of chronic kidney disease (CKD). Vegetarians generally avoid all animal products, including eggs, beef, pork, poultry, fish, seafood and all other living sources of food. However, there is variety of types of vegetarianism, including ovo-vegetarian (eggs only), lactovegetarian (milk and dairy products) and pescatarian (fish is allowed). Most vegetarians do not avoid dairy products while vegans avoid all meat (animal) products and dairy products. Strict vegans avoid even butter.
Advantages of Vegetarianism
Dietary protein restriction may improve determinants of CKD progression. Rediscovery of the Mediterranean diet, rich in vegetables, legumes and cereals, and demonstration of their association with longer survival, call for attention to traditional diets that are easily modified into low-protein diets. There is evidence of increasing mortality, cardiovascular diseases and cancer linked to diets that are rich in red and processed meat. Vegetarian and vegan diets are becoming increasingly popular, setting the groundwork for easier integration of vegetarian protein-restricted diets in our patients who are no longer seen as ‘outliers.’ Vegetarian diets are considered safe by the most eminent associations, including the Academy of Nutrition and Dietetics, provided that deficits of vitamins and minerals like iron, vitamin B12 and vitamin D are corrected.
Maintaining a Balance through the Stages of Kidney Disease
Some patients may require protein calorie supplements, depending on albumin level and co-existing inflammatory conditions. Balancing phosphorus can be a challenge and extra binders may be required in order to include whole grains, beans and nuts.
Diet recommendations differ for patients with CKD stages 2 through 4 versus stage 5. The protein recommendation for patients with CKD stages 3 and 4 is 0.6 to 0.8 g/kg/day. Vegetarian diets usually contain between 0.6 and 0.8 g/kg/day of vegetable proteins and may be less damaging to kidneys, since vegetable proteins are less bioavailable than animal proteins. CKD stage 5 patients require a higher amount of protein, 1.0 to 1.2 g/kg/day, due to protein loss during dialysis and other catabolic processes.
Little is known about the toxic effect of phosphorus food additives, preserving agents or taste enhancers in ready-to-eat and processed foods. Recent studies highlighted the importance of added polyphosphates and warned about sodium and potassium content. This is especially important for vegetarians as most textured protein foods are preserved and have high sodium content. Sodium and potassium should be limited to 2,000 mg/day for most patients on dialysis. Phosphorus is usually not included on the nutrition label but is included in the ingredient list. I recommend avoiding foods with ingredients that include “phos” in the name because 90 to 100 percent of phosphorus from inorganic phosphorus (in additives) is absorbed quickly and easily and therefore should be avoided.
In summary, a vegetarian diet can be a positive influence for patients with kidney disease, and can aid with limiting protein and phosphorus consumption. Vegetarians depend on plants, beans and nuts as their protein source—and, according to some studies by Kalantar et al, less than 50 percent of these organic sources of protein are absorbed by the gastrointestinal tract. Because humans do not express the degrading enzyme phytase, the bioavailability of phosphorus from plant-derived food is relatively low.
Note: Some of the content within this article has been republished with permission from Nephrology News & Issues.
Ms. Patel also authored this vegetarian article for kidney patients, which includes related recipes.