Benefits of Plant-Based Eating in Kidney Disease, Part 1

Traditionally, plant-based diets have been considered the wrong choice for some patients with chronic kidney disease (CKD) due to their high potassium content. However, recent studies show plant-based diets may slow the progression of kidney disease and have other benefits for overall health.¹ In this first part of a two-part series, we’ll discuss benefits of a plant-based diet in CKD, including its effects on weight, blood pressure, diabetes and inflammation.

Weight

There are lower rates of obesity and overweight among vegetarians in the general population.² One diet and weight researcher, Mozaffarian, and team found that eating plant-based foods did not contribute to weight gain.³ Studies have also found that eating a vegetarian diet unrestricted in calories for more than four weeks was associated with an average weight loss of 7.5 pounds.⁴ More research is needed on the effects of plant-based diets on body weight, specifically in people with CKD.

Blood Pressure

Diets like the Dietary Approaches to Stop Hypertension (DASH), which include high intake of fruits and vegetables, are recommended to improve blood pressure in the general population.² There are limited studies that include CKD patients. One study, by Goraya and others, compared the treatment of metabolic acidosis with sodium bicarbonate tablets to a base-producing fruits and vegetables diet in people with stage 4 CKD.⁵ In addition to the fruits and vegetables diet improving metabolic acidosis, systolic blood pressure was lower compared to the group treated with sodium bicarbonate at 1 year.

Diabetes

Insulin resistance is a risk factor for cardiovascular disease.² Insulin resistance is common in all stages of CKD. In a population of people with diabetes, ovo-lacto-vegetarians (vegetarians whose diet includes dairy products, eggs, vegetables, fruits, grains and nuts) showed higher insulin sensitivity compared to the meat eaters and the degree of sensitivity correlated with years following a vegetarian diet.⁶ A review of several studies on people with diabetes found that a vegetarian diet combined with exercise was associated with a reduction in the use of glucose-lowering medications and hemoglobin A1c.⁷ There are few studies including CKD patients. A small study found that after three months following a plant-based protein diet, fasting glucose levels were reduced in patients with CKD stages 4-5.⁸

Inflammation

Uremic toxins are produced during the breakdown of amino acids. Normally, the toxins are removed by the kidneys, but in people with CKD the toxins build up in the blood.⁹ The toxins contribute to inflammation and oxidative stress and increase risk for cardiovascular disease and insulin resistance. Production of uremic toxins are affected by the diet. A diet high in animal protein produces more uremic toxins. A diet high in plant protein can reduce the levels of uremic toxins. Researcher Wu and team found that in dialysis patients, a vegetarian diet was associated with lower serum blood urea nitrogen, creatinine and C-reactive protein.¹⁰

Summary

Plant-based diets have been studied more in the general population and have been found to aid in weight loss, blood pressure control, diabetes control and inflammation. There are some studies that include people with CKD that have found the same benefits as in the general population. So, keep eating those fruits and vegetables! A plant-based diet may help people with CKD maintain a healthy weight, lower blood pressure and glucose levels, and help decrease inflammation.

Look for Part 2 in this series that discusses a condition called metabolic acidosis and how plant-based diets can improve it.

References:

1. What is a Plant-based Diet, and Is it Good for Your Kidneys? National Kidney Foundation. Accessed March 3, 2021. Reviewed August 18, 2018. https://www.kidney.org/atoz/content/what-plant-based-diet-and-it-good-kidney-disease.
2. Vegetarian diet and chronic kidney disease. Chauveau et al. Nephrology Dialysis Transplantation. 2019, 34:199-207. https://academic.oup.com/ndt/article/34/2/199/5049714.
3. Changes in diet and lifestyle and long-term weight gain in women and men. Mozaffarian et al. New England Journal of Medicine. 2011, 364:2392-2404.
4. A systemic review and meta-analysis of changes in body weight in clinical trials of vegetarian diets. Barnard et al. Journal of the Academy of Nutrition and Dietetics. 2015, 115:954-969.
5. A Comparison of Treating Metabolic Acidosis in CKD Stage 4 Hypertensive Kidney Disease with Fruits and Vegetables or Sodium Bicarbonate. Goraya et al. Clinical Journal of the American Society of Nephrology. 2017, 8(3):371-381. https://cjasn.asnjournals.org/content/clinjasn/8/3/371.full.pdf?with-ds=yes.
6. Insulin sensitivity in Chinese ovo-lactovegetarians compared with omnivores. Kuo et al. European Journal of Clinical Nutrition. 2004, 58, 312-316.
7. Vegetarian diets and glycemic control in diabetes: A systemic review and meta-analysis. Yokoyama et al. Cardiovascular, Diagnosis, and Therapy. 2014, 4, 373-382.
8. Low protein diet in uremia: effects on glucose metabolism and energy production rate. Rigalleau et al. Kidney International. 1997, 51:1222-1227.
9. Vegetable-based diets for chronic kidney disease? It is time to reconsider. Cases et al. Nutrients. 2019, 11, 1263. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6627351/pdf/nutrients-11-01263.pdf.
10. Nutritional status of vegetarians on maintenance hemodialysis. Wu et al. Nephrology (Carlton). 2011, 16, 582-587.

Additional Kidney Diet Resources

Visit DaVita.com and explore these diet and nutrition resources:

• DaVita Food Analyzer
• DaVita Dining Out Guides
• Today’s Kidney Diet Cookbooks
• DaVita Kidney-Friendly Recipes
• Diet and Nutrition Articles                                                       
• Diet and Nutrition Videos
• Kidney Smart® Virtual Classes

This article is for informational purposes only and is not a substitute for medical advice or treatment. Consult your physician and dietitian regarding your specific diagnosis, treatment, diet and health questions.