The Challenges of a Vegan Diet for Kidney Patients

The best diet pattern for managing chronic kidney disease(CKD)isnotknown. A major challenge is thatdietaryneedschangewiththeprogressionof the disease. IntheearlystagesofCKD,choosing a healthy diet pattern will help to reduce the risk of chronic disease and manage other health conditions.A well-planned vegan diet of legumes, whole grains, whole fruits, vegetables, nuts and seeds may help to reduce risk of heart disease, andalsomanagebloodsugarandbloodpressure for those who also have diabetes or high blood pressure.

InthelaterstagesofCKD,therearerisksand benefits to following a vegan diet. MostAmericans consumemorethanenoughproteinandcalories, but not everyone with CKD. Manypeopleinthe laterstagesofCKDaremalnourishedandsome areunderweight. Choosing to follow a vegan diet which is often lower in protein and calories may increase the risk of malnutrition. Ifavegan diet pattern is chosen, it needs to provide enough protein and calories.

Weight loss may be recommended in the early stagesofCKDtoreducetheriskofheartdisease, and manage blood pressure and blood sugar in those with high blood pressure and diabetes. If weightlossispursued,itisveryimportantto preservemuscleassomemuscleisalwayslost with weight loss. Musclelosscanbeminimized witharecommendedexerciseprogram.

Weight loss is risky in the later stages of CKD. People with lower body weights or BMI (Body Mass Index – a comparison of weight to height) have worse outcomes and survival compared to thosewhoareoverweight.Theoppositeistruefor those without CKD.Thisisknownasthe“obesity paradox”. Someextraweightseemsprotectivein the later stages of CKD.Any weight loss, planned or unplanned, should be discussed with a health professional specializing in kidney disease.

Some people with CKD may not be getting enough vitamin D, which may lead to osteoporosis, and also decreased immune function and muscle strength. Zincintakemayalsobelowwhichcan leadtopoorwoundhealing. Intake of long chain omega-3 fats, important for heart health, may

also be low.Thesearethesamenutrientsthat arelowinavegandiet. A consultation with a registered dietitian is needed to ensure the vegan diet supplies all the needed nutrients as well as any restrictions needed to manage CKD.

Often in the later stages of CKD, blood levels of phosphorus are too high. Meat,dairyand otherproteinfoodscontainhigheramountsof phosphorusthatiseasilyabsorbed,increasing

bloodlevels.As vegans avoid meat and dairy, this cutsouttwomajorsourcesofphosphorus.Vegan proteinfoods,soyandotherbeans,arealsohighin phosphorus,butthisphosphorusisnotabsorbedas well as animal sources and has less of an effect on bloodlevels. Caution is needed though, as many processed foods have “hidden sources” of added phosphorus. Frozenentreesandotherprocessed veganfoodsmayhaveaddedphosphorus.

Unfortunately, the phosphorus content of packaged foods is not listed on the Nutrition Facts panel making it difficult to know which foods are high inaddedphosphorus. Checking the ingredient list on packaged foods is helpful.Avoid foods with ingredients including the words “phosphate” and“phosphoricacid”. Preparing foods from scratch is the best way of limitingaddedphosphorus.

Vegan diets are higher in potassium which may pose a risk for those withlowkidneyfunction. If blood levels of potassium increase, lower potassiumfoodsneedtobeemphasized. Fortunately, packaged foods willsoonhavethepotassiumcontentlistedontheNutritionFactspanel, whichwillmakeitmucheasiertoidentifyfoodshighinpotassium.

A major health advantage of vegan diets is the high fiber. Heartdisease is common in people with CKD, but those who consume higher intakes offiberhavelowerriskofheartdisease. Higher fiber diets are linked to increasedsurvival.Vegan foods such as legumes, whole grains, fruits, vegetables, nuts and seeds are all good sources of dietary fiber. Inthe later stages of CKD, when some of these foods may need to be restricted, choosingfoodswithaddedfibermayhelptoincreasefiberintakes.

Once dialysis is started, does the vegan diet need to be abandoned? Is there a difference in health between people on dialysis that choose avegetarianornon-vegetariandiet?Dialysispatientsfollowinga vegetariandiethavelowermusclemassandBMI(bodymassindex). They also have less inflammation which is beneficial.Theyhave similar rates of malnutrition and activity levels.

Unfortunately, these comparisonshavenotbeenmadewithvegans. More research is needed to test the risks and benefits of following a vegan diet while on dialysis. Mostresearchonvegetariandietsandkidneydiseasehasbeenwith lacto-ovovegetariansandnotwithexclusivelyvegans. Muchofthe research has focused on specially supplemented low protein vegetarian dietsandnotveganorothervegetariandietsachievingusualprotein intakes.

Vegans consume fewer calories and less protein than other vegetarians andevenlesssothanmeat-eaters.Vegetariandiets,includingvegan diets, can be nutritionally adequate for all ages of healthy individuals if they areplannedwell. Ifnotwellplanned,vegandietsmaybelowiniron, vitaminB12andothernutrients. Having kidney disease and choosing a vegan diet poses additional challenges that can be overcome with the help of a registered dietitian/nutritionist specializing in kidney disease.