CONSCIOUS TABLE, GETTY IMAGES/JENIFOTO
Around 37 million persons in the United States have chronic renal disease, according to the Centers for Disease Control and Prevention. The CKD nutrition recommendations up until recently were more concerned with restricting particular minerals including potassium, phosphorus, and sodium. Because of this, numerous plant foods were frequently banned for persons with CKD, including whole grains, fruits, and vegetables, all of which are higher in these nutrients.
The 2020 Kidney Disease Outcomes Quality Initiative (KDOQI) Clinical Practice Guideline for Nutrition in CKD, developed in collaboration with the Academy and based on more recent research, however, suggests putting more of an emphasis on the quality of the entire diet, which includes more plant foods. This strategy may be more successful than strictly adhering to nutritional ranges at slowing the course of CKD when combined with a personalised nutrition intervention.
According to some study, eating styles that prioritize plant-based foods, such as the Mediterranean, DASH, Nordic, vegan, and vegetarian diets, are linked to better kidney health results. People who follow these eating habits have a lower prevalence of CKD. Additionally, when people with CKD adopt these eating habits, their condition frequently advances more slowly.
Animal vs. Vegetable Protein
Reduced protein intake and close monitoring are recommended for persons with CKD stages 3 through 5 who are “metabolically stable” and not receiving dialysis, according to the KDOQI guidelines and the Academy’s Evidence Analysis Library. The guidelines are based on the most up-to-date knowledge as of April 2017, however even while both declare that there is not enough evidence to advocate one protein source over another — i.e., animal versus plant protein — there may be a cause to give this another look (or through August 2018 for any of the consensus opinion statements).
According to Annamarie Rodriguez, RDN, LD, FAND, “While there was insufficient research to warrant a strong recommendation at that time, more proof in favor of plant-based proteins has subsequently been published, who has worked as a nephrology dietician for almost 25 years, has held positions in the Academy and affiliated organizations and has served on a number of boards of renal-related organizations. She manages a private practice and a full-time job with an infusion firm.
Whether or not plant proteins are the primary source of protein consumption, there is enough data to suggest the advantages of consuming more plant foods and plant proteins
Plant foods for CKD: Benefits
People with CKD may benefit from eating plant protein and following a plant-based diet if they experience less inflammation, fewer uremic toxins, less metabolic acidosis, improved gut microbiome due to increased fiber intake, and decreased bioavailability of certain nutrients like phosphorus and potassium.
Inflammation and associated inflammatory diseases are more common in people with CKD. For instance, 65% of those with CKD also have cardiovascular disease, and between 50% and 75% of those with CKD also have cardiovascular disease and Type 2 diabetes. For those with CKD, cardiovascular disease is the leading cause of death.
Lower comorbidities and inflammation have been linked to diets richer in plant foods, including as the Mediterranean, DASH, and vegan and vegetarian diets. A 2019 study discovered heart-protective advantages from consuming at least 800 grams of fruits and vegetable day, or roughly five servings. Rodriguez adds that there are numerous epidemiological studies that support the benefits of higher fruit and vegetable diet in terms of protection and anti-inflammatory properties.
When considering the comorbid diseases and inflammatory response mechanisms that are produced by CKD, Rodriguez believes that the phytochemicals and antioxidants in fruits and vegetables are really necessary for what our patients need. “The most natural method to fight it is to eat a lot of fruits and vegetables.”
Because of the kidney’s diminished capacity to filter and eliminate acids through urine, metabolic acidosis, or the accumulation of too many acids in the blood, can both contribute to and be a result of CKD. Osteoporosis, insulin resistance, other endocrine diseases, muscle atrophy or protein energy squandering, and deteriorating kidney disease can all result from excessive acid in body fluids.
According to Rodriguez, eating a lot of animal protein encourages the creation of acid because amino acids like methionine and cysteine, which are oxidized to sulfate, contain organic sulfur. “Plant-based foods, such as fruits, vegetables, and legumes, naturally include precursors to the alkaline state, such as citrate and malate.
which are transformed into buffering serum bicarbonate.” Rodriguez contends that while there are oral alkali medicines, eating a diet rich in alkaline foods can be just as helpful while offering the advantages of fiber, antioxidants, and phytonutrients that are sometimes lacking in the historic or typical CKD diet.
A diet richer in fruits and vegetables is helpful in treating and avoiding metabolic acidosis, according to reviews from 2013 and 2015. For persons with CKD stages 2, 3, and 4 and metabolic acidosis, randomized controlled trials conducted in 2012, 2013, and 2014 indicated that consuming more fruits and vegetables was just as helpful as taking oral sodium bicarbonate.
Even if patients or clients aren’t prepared to give up animal-based proteins, Rodriguez says might be balanced out by finding ways to consume more plant foods, like fruits and vegetables.
Potassium and phosphorus bioavailability
Once upon a time, the CKD diet for individuals with CKD stages 3 through 5 and on dialysis was built around tight restrictions on foods high in phosphorus and potassium. People generally as a result limited their intake of plant-based diets. The body does not completely absorb all of the phosphorus and potassium found in plant sources, according to a study, which indicates that these nutrients are less accessible in plant diets. According to a 2018 study, animal proteins like meat, poultry, and fish may include phosphorus and potassium additions in a more accessible form. The revised KDOQI recommendations advise practitioners to take the bioavailability of phosphorus sources into account.
Every time I discuss increasing the intake of plant-based proteins in CKD patients with dietitians, they are more worried about potassium and phosphorus, according to Rodriguez. She says that some plant meals contain phytic acid as their source of phosphorus, which is largely indigestible by people because they lack the enzyme phytase, which transforms phytic acid into a more accessible form of phosphorus. She claims that the higher fiber content in plant-based diets may assist lessen phosphorus and potassium absorption. Additionally, when consuming more plant-based foods, recently developed potassium binders can assist patients and clients maintain normal serum potassium levels.
Though Rodriguez claims she always shares this with her patients or clients, processing like sprouting, fermenting, and boiling can make phosphorus more accessible. According to Rodriguez, registered dietitian nutritionists should inform their patients or clients about inorganic sources of phosphorus, which are frequently included in highly processed meals and drinks like soda. The body absorbs the majority of additional (or inorganic) phosphorus.
Only 10% of persons with non-dialysis CKD are anticipated to ever see an RDN, despite the astounding number of people who have CKD and the potential for medical nutrition therapy to delay the disease’s course. Lack of physician understanding and referrals, as well as RDN accessibility, may be barriers to MNT. RDNs might want to think about promoting the significance of diet for CKD whenever possible, regardless of the reason.
The expense of visiting a dietician may deter some persons from receiving or requesting medical nutrition therapy. RDNs in private practice may want to think about signing up with Medicare, which covers a limited number of appointments for CKD enrollees, in order to lower the cost of appointments, who were referred by a doctor and are not currently receiving kidney transplantation or dialysis.
Patients or clients could have preconceived assumptions or prejudices that consuming fruits, vegetables, and whole grains will negatively affect the course of their disease. Present the newest research, outline the advantages of consuming more plant-based foods, and develop a personalized care plan when counseling patients or clients. Stress the benefits of small, steady adjustments over time if patients or clients are not ready to make significant changes.
Rodriguez asserts that even modest objectives and baby actions can have an important influence on health outcomes. Simple changes, like substituting one or two meals each week for plant-based options, can make a big difference, according to health consciousness.
TO LEARN MORE
To learn more about the advantages of a plant-based diet for CKD and applicable strategies, view these Academy webinars:
The New Benefits of a Plant-Based Approach to Chronic Kidney Disease Diet Plant-Based with Chronic Kidney Disease
Stages 1–5 of Medical Nutrition Therapy for Chronic Kidney Disease without Dialysis
Certificate of Training in Nutrition Management for Chronic Kidney Disease.