Approximately 1 in 3 adults with diabetes, encompassing both type 1 and type 2, are at risk of developing chronic kidney disease (CKD). Medical nutrition therapy should be based on the person’s CKD stage and comorbidities and take into consideration the person’s lifestyle, food preferences, and cultural background and the importance of maintaining the enjoyment of eating.1 The 5 stages of CKD are categorized based on the estimated glomerular filtration rate (Table 1).2
Medical nutrition therapy can play a vital role in slowing or preventing the progression of CKD and aiding in the prevention of complications, such as malnutrition, dyskalemia, metabolic acidosis, and mineral and bone disorders.
Before discussing how to make the kidney diet more culturally inclusive, it is important to understand how previous recommendations inadvertently led to this becoming an issue. Renal nutrition involves the close monitoring of many components, including fluid gains and certain nutrition labs,3 such as albumin, calcium, phosphorus, and potassium. Kidney Disease Improving Global Outcome (KDIGO) and Kidney Disease Outcome Quality Initiative (KDOQUI) periodically publish renal nutrition guidelines. Prior to the 2020 KDIGO/KDOQUI updates, there were 4 key recommendations:4
encouragement of animal protein consumption,
avoidance of whole grains due to their higher phosphorus content,
avoidance of dairy due to its potassium/phosphorus content,
avoidance of fruits and vegetables due to their high potassium and/or phosphorus content.
In an effort to keep kidney patients at safe laboratory levels, this approach unfortunately presented challenges for many populations, particularly those who felt their cultural foods were being excluded, especially foods higher in phosphorus and potassium. Additionally, the provision of prescriptive lists of foods that were “allowed” and “discouraged” without consideration for the amount of nutrients, cooking methods, or nutrient absorbability often resulted in patient demoralization and a perception of unrealistic or impractical recommendations in clinical practice.
The 2020 KDIGO/KDOQUI guidelines incorporated several key updates:5
Removal of the animal protein requirement;
encouragement of plant-based foods, including whole grains;
inclusion of 1 serving of dairy per day;
focus on limiting foods high in added phosphorus and potassium preservatives.
Compared to prior recommendations, there was a noticeable shift toward a plant-based dietary pattern. A big emphasis was also placed on factors that affect the absorption of phosphorus and potassium, including cooking methods, and the distinction between organic phosphorus and potassium found in food and phosphorus/potassium additives (Table 2).6 This is vital when incorporating recommendations for cultural foods in relation to products and portions.
The first step in being more culturally inclusive as health care professionals working with the renal population is to individualize recommendations based on lab results and not overrestrict when it is not warranted. And if a lab value is out of range, for example if potassium is elevated, instead of immediately making a recommendation to restrict certain plant foods, such as tomatoes, potatoes, or mangoes, first investigate the underlying etiology for abnormal labs.5 If the lab can be corrected by addressing other underlying issues, this will eliminate the need to further restrict their cultural foods.
Gastrointestinal problems
♦ Does the patient have Gastrointestinal disturbances? Nausea can impact intake, vomiting and diarrhea can cause abnormally low labs, and constipation can cause elevated labs.
Dialysis issues
♦ Did the patient miss a treatment or shorten treatment time? Do they have problems with their access or inadequate dialysis?
Blood glucose
♦ Is blood glucose within range? When blood glucose is elevated, potassium leaves the cell and enters the blood, raising potassium levels.
Pharmaceutical interventions and considerations
♦ Phosphorus and potassium binders
✧ Binders are medications that bind to the phosphorus or potassium from foods in the gastrointestinal tract and keep it from being absorbed by the body.
✧ Does the patient know how to take the binders, and are they being consistent?
✧ Has there been a change in binder availability?
♦ Other medications affecting potassium
✧ Has there been a change in medications for the patient that are potassium sparing or potassium wasting (blood pressure medications, diuretics, etc)?
♦ Other medications affecting phosphorus7
✧ Active vitamin D
✧ Certain blood pressure medications
✧ Certain NSAIDS
✧ Reflux medications
♦ Medications affecting calcium5
✧ Calcium-containing binders
✧ Calcium-containing antacids
✧ Calcimimetics
If all nondietary factors have been addressed with the patient and laboratory goals are still not being met, we can discuss nutrition recommendations keeping a cultural lens in mind. It all begins with an in-depth dietary recall because many different aspects of cooking can be impactful on renal labs and fluid gains. Ensure that you are asking for clarification on how meals are prepared and seasoned, brands frequented, and portions.
Examples of recall questions and relevance in renal nutrition include the following:
How are your foods cooked? Fried, steamed, boiled?
✧ Beans and potatoes may be leached up to less than 200 mg of K+ per serving if double boiled.8
With what do you commonly season/marinate your foods? Do you use soy sauce, chicken bouillon, salt substitutes?
✧ Lower sodium and salt-free seasonings may contain potassium chloride.
What is the consistency of your foods?
✧ Do you use a lot of curries, soups, broth? This will count toward the fluid allowance.
For patients with CKD/end-stage kidney disease, the nutrition label can be helpful in finding those highly absorbable potassium9 and phosphorus6 additives in the ingredient list. A few examples include the following:
phosphoric acid
monosodium phosphate
monocalcium phosphate
potassium diphosphate
potassium chloride.
Teaching patients how to identify these additives can help them make the right choice of which brand of their cultural foods to choose. For example, if a patient were trying to choose which Mexican hot chocolate brand to enjoy, it would be helpful for them to know which ones contained phosphorus and potassium additives and which ones did not.
However, the nutrition label can be misleading in the amount of potassium in foods. Due to the zero-rounding rule,10 food companies can label their foods as potassium free as long as the food item contains less than 2% of the daily value of potassium (4700 mg) per portion.
Guiding the patient in the portion of each individual ingredient being used in a meal is what will ultimately help them be able to include their favorite cultural foods safely. Discuss with the patient if there are some higher phosphorus or potassium foods that they would like to incorporate into their diet and work with them by providing visuals and helping them adjust recipes to incorporate safe amounts of these foods. For potassium, educate on how concentrated foods (dried fruits, juices, sauces) will contain more.
Mariela faced dietary restrictions after she was told by Dr M to limit her intake of beans. She also believed from online research that avocados, despite being a healthy fat, were too high in potassium for her to consume regularly. She sought guidance with a dietitian on incorporating her favorite cultural dishes, such as black bean tostadas, into her diet.
Upon meeting Mariela, the dietitian explains to her that needing to completely avoid beans or avocados is an outdated practice and that with proper guidance, her cultural foods can be successfully included in her kidney diet. Mariela began by listing the ingredients for her desired black bean tostadas. This step was crucial in identifying potential sources of higher sodium, phosphorus, and potassium, which needed to be balanced with alternatives.
Because Mariela’s latest phosphorus and potassium levels were within target ranges, this allowed them to explore appropriate portions of beans and avocado. Mariela was educated on the varying potassium and phosphorus content in foods, emphasizing the importance of moderation and balance.
Mariela and the dietitian collaborated on creating meal ideas that aligned with Mariela’s preferences while managing sodium, phosphorus, and potassium levels effectively. Detailed discussions included cooking methods, such as double boiling beans to reduce potassium content. This empowered Mariela to make informed choices and manage her nutrient intake effectively.
To further support Mariela, the dietitian determined appropriate portion sizes based on lab trends and her nutritional requirements. Mariela was encouraged to use measuring utensils and her own estimation techniques when dining out, ensuring consistency in portion management until she felt confident with her choices.
Mariela’s journey exemplifies the importance of personalized nutrition guidance in managing dietary restrictions. By combining education on nutrient values, practical cooking methods, and portion control strategies, a person with CKD can successfully incorporate cultural foods into their diet.
It can be very overwhelming for a patient to be able to navigate the kidney diet, especially when receiving conflicting and outdated information. It is our duty as health care professionals to provide updated evidence-based recommendations that allow patients to follow their cultural food patterns while still achieving their kidney health goals.
Areli Gutierrez, MS, RD, LD, is with DaVita Kidney Care in the Houston, TX, area.
The author declares having no professional or financial association or interest in an entity, product, or service related to the content or development of this article.
The author declares having received no specific grant from a funding agency in the public, commercial, or not-for-profit sectors related to the content or development of this article.
Ikizler TA, Burrowes JD, Byham-Gray LD, et al. KDOQI Clinical Practice Guideline for Nutrition in CKD: 2020 update. Am J Kidney Dis. 2020;76(3, suppl 1):S1-S107. doi:10.1053/j.ajkd.2020.05.006. Erratum in: Am J Kidney Dis. 2021;77(2):308.
KDIGO 2012 clinical practice guideline for the evaluation and management of chronic kidney disease. Kidney Int. 2013;3(1):5. doi:10.1038/kisup.2012.74
Linda M. Pocket Guide to Nutrition Assessment of the Patient With Kidney Disease. 6th ed. National Kidney Foundation; 2021
Suki WN, Moore LW. Phosphorus regulation in chronic kidney disease. Methodist Debakey Cardiovasc J. 2016;12(4 suppl):6-9. doi:10.14797/mdcj-12-4s1-6
Ikizler TA, Burrowes JD, Byham-Gray LD, et al; KDOQI Nutrition in CKD Guideline Work Group. KDOQI clinical practice guideline for nutrition in CKD: 2020 update. Am J Kidney Dis. 2020;76(3, suppl 1):S1-S107.
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Sawin DA, Ma L, Stennett A, et al. Phosphates in medications: Impact on dialysis patients. Clin Nephrol. 2020;93(4):163-171. doi:10.5414/CN109853
Martínez-Pineda M, Vercet A, Yagüe-Ruiz C. Are food additives a really problematic hidden source of potassium for chronic kidney disease patients? Nutrients. 2021;13(10):3569. doi:10.3390/nu13103569
Martinez-Pineda M, Yague-Ruiz C, Caverni-Munoz A, Vercet-Tormo A. Cooking legumes: a way for their inclusion in the renal patient diet. J Ren Nutr. 2019; 29(2):118-125. doi:10.1053/j.jrn.2018.08.001
Center for Food Safety and Applied Nutrition. Guidance for industry: nutrition and supplement facts labels questions and answers related to the compliance date, added sugars, and declaration of quantitative amounts of vitamins and minerals. Revised December 2019. Accessed October 2023. www.fda.gov/regulatory-information/search-fda-guidance-documents/guidance-industry-nutrition-and-supplement-facts-label-squestions-and-answers-related-compliance