- Removing waste and extra fluid as urine
- Balancing electrolytes, like sodium and potassium
- Producing red blood cells
- Regulating blood pressure
- Controlling pH balance
- Making an active form of Vitamin D to support bone health
Nearly 1 in 7 Americans have chronic kidney disease (CKD), with millions more at risk. The incidence of CKD is increasing due to the prevalence of obesity, Type 2 diabetes, and hypertension in our society. As many as two-thirds of all cases of CKD can be attributed to poorly controlled blood glucose, blood pressure, and excessive weight. Current research is showing that a healthy diet that is high in fruits and vegetables and low in animal protein could help prevent or delay the onset of CKD.
The two dietary patterns that have received the most attention in supporting kidney health include the Mediterranean diet and the Dietary Approaches to Stop Hypertension (DASH) diet. Both diets emphasize daily food intake rich in vegetables, fruits, whole grains, nuts, and seeds as well as legumes (beans). The Mediterranean diet specifically encourages the intake of seafood and heart-healthy fats like olive oil, while the DASH diet emphasizes low-fat dairy, reducing sugar intake and limiting daily sodium consumption to 1500-2300 mg/day. Both of these diet approaches lower the risk of cardiovascular disease and blood pressure while decreasing inflammation, all of which are beneficial for kidney health.
Excessive protein in the diet has long been questioned as a possible contributor to CKD by causing the kidneys to hyper-filtrate, damaging the kidneys over time. The amount of dietary protein that is healthiest for you depends on your body size, age, gender, and activity level. An interesting study published in the Journal of Renal Nutrition looked beyond the amount of protein in the diet to the type of protein consumed. Our kidneys are responsible for the acid-base pH balance in the body. Diets higher in red and processed meats were associated with an increased risk of CKD due to the increased acid load of a higher animal protein diet. Diets similar to the Mediterranean and DASH diets with a higher intake of nuts, seeds, and legumes produced more bicarbonate (base) in the body which was associated with a lower risk of CKD. The takeaway message for dinnertime, therefore, is to limit red meat to no more than once per week, consider a vegetarian meal at least once per week (or as often as you can), and incorporate fish and skinless poultry throughout the rest of the week’s dinnertime meals. If you are looking for vegetarian meal ideas, check out easy vegetarian recipes on the Meatless Monday website.
A discussion about kidney health cannot be complete without mentioning fluid intake. Hydration is essential for kidney function. Ideally, urine should be clear or straw-like in color. To attain this, most adults require 8-12 cups of fluids per day or 64-96 ounces. While it is true that many beverages such as coffee, tea, and soft drinks provide fluid, they also can act as diuretics, artificially increasing the amount of water and salt removed from the body. If you drink alcohol, which is a diuretic, limit to 1-2 servings per day (one serving is either 5 ounces of wine or 12-ounce beers or 1.5 ounces of liquor) and avoid binge drinking (4-5 servings over a few hours) as it can cause acute kidney damage. Water as your main beverage of choice is your best bet. Not crazy about plain water? Steeping herbal tea and drinking it hot or chilled is a tasty option. Be more creative and infuse your water with fruit, vegetables, and herbs. One great site to get you started is http://www.infusedwaters.com/ which posts recipes and tips to make the water you drink more interesting and delicious.
Here’s one of my favorite water recipes:
- 1/2 pint blueberries
- 1 lemon, sliced thinly
- 4 sprigs of fresh rosemary
- 5 cups of water
Place all ingredients into a large pitcher (I prefer glass) and add the water. Refrigerate for at least 1 hour or even overnight before tasting. Add ice if desired.
Keeping your kidneys well for a lifetime might mean making some changes in the foods you choose—whether or not you need to lose weight, or improve your blood pressure or blood glucose levels. A registered dietitian can help you make the changes that will have the biggest impact on your kidney health in ways that work best for you. Enjoy exploring new meal planning tips and recipes—your kidneys will appreciate your attention!
Updated October 2022