By Anna Richardson, MPH RD
Many people with kidney disease may experience a decrease in appetite, taste changes, or digestive symptoms that can lead to unintended weight loss. If you have kidney disease, the dietary recommendations can sometimes feel overwhelming. If you are also trying to increase your intake to maintain or gain weight, this can feel like an extra challenge to navigate.
Studies show that maintaining a healthy weight and avoiding unintended weight loss can help improve health outcomes for people with kidney disease. A diet that meets your energy needs will help you preserve your muscle mass, maintain a healthy weight, and help you feel your best.
How do I eat more calories with a CKD diet? There are many foods that can be easily added to your diet that will stay within your sodium, phosphorus, and potassium goals. Speak to your Dietitian about what high-calorie foods would be best for you.
For many people, adding more calories through all 3 macronutrients (fats, carbohydrates, and protein) is a healthy strategy. However, some people may need to limit their protein intake depending on their stage of kidney disease, so adding more fats and carbohydrates will be helpful.
Adding fats
Vegetable oils (ex. canola oil, sunflower oil, corn oil) are unsaturated fats that contain no sodium, potassium, or phosphorus. Add extra if you are roasting, baking, sautéing or stir-frying. For example, add an extra drizzle of vegetable oil to roasted chicken thighs or stir-fried broccoli and red pepper.
Olive oil: use as you would vegetable oil, or add an extra spoonful to salad dressings, breads, or pasta dishes.
Nuts and nut butters: although nuts do contain potassium and phosphorus, many people can incorporate a handful of nuts or a spoonful of nut butter as a snack. Nuts contain heart-healthy fats to help you up your calories.
Avocado: an excellent high fat food, although people on a potassium restriction will need to limit it.
Butter and margarine: add to toast or sandwiches for extra calories.
Higher fat dairy products: Add a splash of cream to your coffee or tea, spread cream cheese on a bagel or sandwich, or swirl some sour cream into a stew or casserole. As a sweet treat, have ½ cup of ice cream.
Adding carbohydrates (starches and sugars)
Rice, breads, pasta, noodles and cereals are all excellent sources of energy. Some people with CKD may need to limit their intake of whole grains. If double-boiled, potatoes can also be an excellent carbohydrate source that is safe for people limiting their potassium intake.
Sugars – many treats and desserts can be safely enjoyed on a CKD diet. Cookies such as digestive biscuits, arrowroot cookies, and shortbread are all low in potassium. Jams, honeys and granulated sugars can be used to help increase calories. People with diabetes will need to limit added sugars or speak with their Registered Dietitian.
Adding proteins
Meat, fish and poultry are all excellent protein sources that can be enjoyed regularly. Take care to avoid very processed meats such as frozen breaded chicken or fish, deli slices, and cured meats as they are high in sodium. Adding unprocessed meats to soups, stews and sheet pan meals are great ways to get enough protein.
Eggs: usually inexpensive and versatile! Although eggs do contain cholesterol, more recent studies show that in general, people with CKD can eat eggs regularly without negative effects. Add a boiled egg to breakfast or enjoy an omelet or egg sandwich for extra protein.
Plant-based proteins: beans and lentils are great sources of protein, fibre, and other nutrients. Add ½ cup of beans to rice dishes, soups, or enjoy bean dips such as hummus. Although CKD diet guidelines traditionally recommend limiting bean and lentil intake, recent research shows that phosphorus is not as well absorbed from plant sources and many people can enjoy them more frequently. Other plant-based proteins such as tofu, tempeh and soymilk are also excellent sources of protein.
Protein powders: supplements such as whey protein powders and others (ex. soy protein, brown rice protein, pea protein) can be mixed into a smoothie or shake, or even added to oatmeal, yogurt or soups.
Oral Nutrition Supplements
Meal replacement beverages, also called oral nutrition supplements, can help add calories to your diet. These beverages can be a very convenient choice as they are ready to drink and can be taken on the go. Kidney disease-specific nutrition supplements are also available. These are lower in potassium and phosphorus. Your dietitian can suggest an oral nutrition supplement that will work best for your goals.
Not only is what you eat important, but how!
Many people find it challenging to eat 3 large meals per day, so it can be useful to eat a small snack every 2-3 hours instead. Bring snacks with you when you are out, and keep ready-made snacks at home so you can make sure you are getting enough even if you are busy or tired. Consistency is key! Making sure that you are adding extra calories every day is the best strategy to promote weight maintenance or gain.
References
Carrero, J.J. et al. (2013) ‘Etiology of the protein-energy wasting syndrome in chronic kidney disease: A consensus statement from the International Society of Renal Nutrition and Metabolism (ISRNM)’, Journal of Renal Nutrition, 23(2), pp. 77–90. doi:10.1053/j.jrn.2013.01.001.
Ryu, H. et al. (2021) ‘Rapid weight change over time is a risk factor for adverse outcomes in patients with predialysis chronic kidney disease: A prospective cohort study’, Journal of Renal Nutrition, 31(6), pp. 569–578. doi:10.1053/j.jrn.2021.01.026.
Tallman, D. et al. (2018) ‘Egg intake in chronic kidney disease’, Nutrients, 10(12), p. 1945. doi:10.3390/nu10121945.