Potential Renal Acid Load and Its Impact on Kidney Disease: Including PRAL Food Chart, List, and Calculator
Understanding the potential renal acid load (PRAL) of food can help you protect your kidneys. We’ve made it as easy as possible to know the PRAL score of your food by including a PRAL list, PRAL food chart, and PRAL calculator in this blog.
My name is Candace Mooney and I’m a registered dietitian and board certified specialist in renal nutrition. I’m here to help you understand PRAL and how it relates to the foods you choose with kidney disease.
Now let’s get started!
How is PRAL related to Your Kidneys?
Your kidneys play a major role in the regulation of acid-base balance. (1)
Healthy kidneys remove acid from the body through urine and then reabsorb bicarbonate (base) in the blood. But when you have kidney disease, the kidneys have trouble removing enough acid, which can lead to metabolic acidosis. (2)
Metabolic acidosis is when the body has an acid content that is too high to support good health. The amount of acid that stays in your blood depends on your stage of kidney disease and the potential renal acid load of the food you consume. (2)
Lowering your dietary acid load will help maintain your acid-base balance when you have kidney disease. (3)
How do you lower your dietary acid load? We have the answer – PRAL!
Analyzing the PRAL will guide you on reducing the amount of acid you produce from food.
What is PRAL?
Foods are given a PRAL value (or score) depending on how much acid or base they produce in your body when they are metabolized (or broken down). The higher the PRAL value, the more acid they produce in your blood when your kidneys aren’t working at 100%.
Your goal is to help your kidneys maintain a good acid-base balance in your blood with the foods you choose. The more negative the PRAL value the more base they produce, which helps your kidneys balance your blood pH. (4)
The Secret to PRAL
You will almost always meet your PRAL goal of being an overall negative value for the day if you eat your recommended 2 servings of fruits and 3 servings of vegetables, along with not going over your recommended grams of protein per day.
The amount of protein in grams (g) per day that is recommended for you personally depends on your body composition, weight history, medical, and surgical history. It typically varies from 35 g to 70 g per day.
The best way to know your personal nutrition prescription is to work with a qualified renal dietitian, like me, or someone like me.
Assessing Your PRAL Intake
Now you know what PRAL is and how it relates to kidney disease, but how do you know the PRAL value of your food?
We are going to break down the four best ways to access PRAL values in this section.
PRAL Formula
The PRAL formula is good for you to be aware of so that you know how the PRAL scores are created. PRAL score is calculated based on a formula containing the dietary intake of protein, phosphorus, potassium, calcium, and magnesium. (5)
The exact formula is PRAL = 0.49 x protein (g/day) + 0.037 x phosphorus (mg/d) – 0.021 x potassium (mg/day) – 0.026 magnesium (mg/day) – 0.013 x calcium (mg/day). (5)
This does take some time to calculate individually, so do not feel like you have to use this formula manually. The following tools are much faster than manually entering this data for all of your food.
PRAL Calculator
One of the best tools you can use for calculating your PRAL intake is a PRAL calculator. You enter the food name, data from the nutrition facts label, and the serving size you’re eating, and it will calculate the PRAL value. Easy peasy!
PRAL Food List
The calculators are great for researching just one food item, but what if you had a comprehensive list of the most popular foods all in one place?
We hear you and have created it!
| Fruit | PRAL Value | Vegetable | PRAL Value |
| Apple (raw with skin) | -1.9206 | Broccoli (raw) | -3.9692 |
| Blueberry | -1.0444 | Collards (raw) | -4.0975 |
| Orange (raw) | -3.581 | Kale (raw) | -8.337 |
| Banana (raw) | -6.9369 | Potatoes (Russet; flesh and skin; baked) | -8.6483 |
| Black Berries (raw) | -2.8039 | Tomatillos (raw) | -4.3256 |
| Pineapple (raw; all varieties) | -2.3354 | Spinach (raw) | -11.8446 |
| Raspberry (raw) | -2.407 | Sweet potato (cooked; baked in skin; without salt) | -8.1881 |
| Strawberry | -2.5427 | Arugula (raw) | -7.8628 |
| Cherries (sweet; raw) | -3.8206 | Squash (winter; all varieties; cooked; baked; without salt) | -8.6619 |
| Raisins | -3 | Zucchini | -6.0011 |
| Dates (medjool) | -13.6711 | Tomato (canned; paste; with salt added) | -17.6662 |
| Mango | -10 | Avocado | -12 |
| Melon | -3 | Carrot | -5 |
| EGGS/DAIRY | PRAL VALUE | GRAINS | PRAL VALUE |
| Egg (whole; raw; fresh) | 9.4162 | Quinoa | -0.191 |
| Yogurt (vanilla; low fat; 11 grams protein per 8 ounce) | 0.1727 | Rice (white; glutinous; cooked) | 0.9198 |
| Milk (whole 3.25% milk; fat) | 0.2128 | Wild rice (raw) | 9.3967 |
| Cheese (mozzarella; part skim milk) | 16.4904 | Buckwheat groats (roasted; cooked) | 0.9812 |
| Cheese (Swiss) | 21.2867 | Couscous (dry) | 7.6004 |
| Cheese (ricotta; whole milk) | 6.1814 | Macaroni (dry; unenriched) | 6.9256 |
| Cheese (cream) | 3.8525 | Bread (whole-wheat; prepared from recipe) | 1.906 |
| BEANS/LENTILS | PRAL VALUE | ANIMAL PROTEIN | PRAL VALUE |
| Beans (kidney; all types; mature seeds; raw) | -8.4118 | Turkey (all classes; skin only; cooked; roasted) | 10.491 |
| Beans (white; mature seeds; canned) | -4.8846 | Chicken (roasting; meat only; cooked; roasted) | 13.8479 |
| Beans (pinto; mature seeds; raw) | -9.5952 | Pork (fresh; ground; cooked) | 12.4381 |
| Beans (black; mature seeds; raw) | -13.58 | Fish (tuna; light; canned in water; without salt; drained; solids) | 12.7089 |
| Tofu (extra firm; prepared with nigari) | 3.4531 | Fish (cod; Atlantic; raw) | 6.5249 |
| Green lentils | 1.58 | Beef (ground; 90% lean meat / 10% fat; patty; cooked; broiled) | 12.5339 |
| NUTS/SEEDS | PRAL VALUE | OTHER | PRAL VALUE |
| Nuts (cashew nuts; dry roasted; with salt added) | 6.4219 | Coffee | -2 |
| Nuts (chestnuts; chinese; dried) | -10.1082 | Green Tea | 0 |
| Nuts (macadamia nuts; dry roasted; without salt added) | -0.4579 | Black Tea | 0 |
| Water chestnuts (Chinese; matai; raw) | -9.962 | Dark chocolate | -2 |
| Peanut butter (chunk style; with salt) | 3.2024 | Nutritional Yeast | 2.7 |
| Sunflower seeds (oz) | 6.3 | Ice creams (vanilla; rich) | 0.496 |
| Walnuts | 0.7 | Molasses | -38.554 |
| Almonds | 0.4 | Agave | 0 |
The ratios will remain the same no matter the serving size, so the PRAL value of each item will not change depending on how much you eat.
The United States Department of Agriculture (USDA) has a PRAL Food Chart that is also very helpful in identifying low-PRAL and high-PRAL foods. We’ve translated this chart into an excel format to make it easier for you to find the food items you’re looking for by using the search bar.
Remember, the lower the PRAL value, the less acid it produces in your body, which helps your kidneys maintain a proper acid-base balance. Aim for a lower PRAL value.
PRAL Food Chart
We’ve created this easy to read PRAL Food Chart that will help you identify which foods have a high PRAL value, low PRAL value as well as different meal options.
One of your meals could be black bean (½ cup, reduced sodium) and white rice (½ cup) bowl with avocado (½ cup), baby kale (1 cup) and mango (1). This meal has the lowest PRAL value of -21!
A quinoa salad with salmon and vegetables is another great option! This meal includes 1 cup of white mushrooms, ½ of a 3-oz salmon filet, ¼ cup of quinoa, 1 cup of raw spinach, ¼ cup fresh parsley, and 2 tablespoons of olive oil for a 0.92 total PRAL value.
A great breakfast option is a poached egg with oatmeal topped with fruit. It includes ½ cup canned full-fat coconut milk, ½ cup Bob’s Red Mill Rolled Oats, 1 banana, ½ cup strawberries and 1 large poached egg for a -4 PRAL value.
A lunch or afternoon snack option would be a peanut butter and apple sandwich with raw veggies. This meal has 1 cup baby carrots, 1 cup broccoli, 2 tablespoons peanut butter, 1 gala apple, and 2 slices of 100% whole wheat bread for a PRAL value of -4.
With any of these meal options, you can add spices and oil to enhance the flavors without changing your PRAL value much!
What labs should you follow when changing the PRAL value of your foods?
Metabolic Acidosis – Bicarbonate
Bicarbonate (CO2) in your blood measures your blood pH. Damaged kidneys have a hard time excreting extra acid in your urine as they were designed.
Normal levels are 22-29 mEq/L, but ideal levels are 24-26. (7)
Lower levels mean your blood is too acidic and your doctor may prescribe something like sodium bicarbonate. You can also affect your serum CO2 levels with the PRAL values of your food.
As we discussed above, animal protein typically decreases your bicarbonate level making your blood more acidic while plants have the opposite effect.
Metabolic Acidosis can cause inflammation which can affect several labs. Learn more about this by checking out our blog post on Renal Lab Values: What You Need to Know from a Renal Dietitian.
Conclusion
Paying attention to the overall PRAL of the foods you choose will help your kidneys better support your body.
The PRAL food chart, PRAL list, and PRAL calculator above are all excellent resources to help you achieve your goal of averaging an overall negative daily value of PRAL.
Remember you are balancing your plate to include fruits and vegetables with a focus on plant based proteins. This doesn’t mean you have to exclude all positive PRAL foods all the time.
If you are just starting out, give yourself the grace to enjoy the foods you love, even if they are higher PRAL foods. I want you to remember that even the tiniest steps are taking you to your destination when you’re thinking about taking steps toward your goals.
You got this!
This article was co-written by dietetic student and digital marketing intern Eva McIntosh & reviewed, edited, and co-written by Candace Mooney, MS RDN CSR.
How do I download free PRAL chart? All I saw was a place to subscribe for a newsletter. Thanks
Hi Mike, when you enter your email and name in that subscription box, you should get an email immediately to download the PRAL chart. Let me know if it doesn’t work for some reason. It will automatically subscribe you to my newsletter but you can hit the unsubscribe link at the bottom of that email to be removed if you like 🙂
Thank you for the informative article. While I do not have kidney disease, I do have stage 1 breast cancer and am learning which foods are best and which aren’t. We know cancer loves an acidic environment, so even though I do not have kidney disease, I assume I could still choose foods that have a better pral score in order to keep my body more alkaline? This seems like an obvious answer, but everything I’m reading about pral is in regards to the kidneys. I guess keeping them in check helps keep my whole body in check in the meantime. Thank you!
You’re welcome Anna! I’m not an oncology dietitian but I agree with you in that it makes sense to think that way! I would assume your kidneys are filtering and managing your acid-base balance fine without needing the help of monitoring PRAL but I do believe eating lower PRAL foods are generally more healthy anyway (higher intake of fruits and veggies, lower intake of animal protein) providing more variety of vitamins and minerals with antioxidants for protection. I do wonder what your protein needs would be and if yours would be higher with stage 1 breast cancer, which might make it harder to eat a lower PRAL diet. And if you are eating less protein, would you need supplements for vitamins and minerals typically found in the animal proteins/protein in general. I hope this response helps you in your journey for good health!
Thank u sooo much. I feel like I am in a food jungle turning this way and that. The dietician my Doc sent me to gave me a hand out and that was it. No info on how not to get to stage 4 ckd. Wish I had a little computer to calculate pral with the values of foods already in it.
Thanks again,
Becky Herndon
You’re welcome Becky! I’m glad you are finding it helpful!