IgA nephropathy (IgAN), also known as Berger’s disease, is an autoimmune condition in which antibodies damage the kidneys’ small blood vessels that filter blood. IgAN often causes chronic kidney disease and kidney failure. Eating nutritious whole foods that are low in salt, protein, phosphorus, and potassium may help people with IgAN avoid additional kidney damage.
There is no single diet plan for individuals with IgA nephropathy, and nutrient needs and restrictions can change over time. In general, people with IgAN may benefit from eating low-sodium, whole foods.
Choosing foods high in antioxidants and omega-3 fatty acids may also help reduce inflammation and support kidney health. People with IgAN may also need to limit their protein, phosphorus, and potassium intake based on their blood work, stage of kidney disease, and kidney function.
Foods High in Antioxidants
Antioxidants help protect the body from oxidative stress, which can trigger IgA inflammatory immune responses. Limited human studies have found that antioxidants may reduce inflammation and slow the progression of chronic kidney disease. Also, research has linked antioxidants to a reduced risk of kidney failure in adults with chronic kidney disease.
Foods high in antioxidants include:
- Apples
- Blueberries
- Strawberries
- Bell peppers
- Broccoli
- Kale
- Walnuts
- Pecans
- Oats
Lean Animal Proteins
Choosing lean proteins can help limit saturated fat that can stress damaged kidneys. Lean meats, poultry, and seafood also contain less phosphorus. This mineral is difficult for the kidneys to remove if you have IgA nephropathy.
Too much phosphorus can harm your blood vessels and bone health. Eating lean cuts of meat offers lower levels of phosphorus that are easier for damaged kidneys to remove. However, lean meats still contain some phosphorus. Keep portion sizes in mind if you are limiting phosphorus in your diet.
Lean meats include:
- 90-93% lean ground beef
- Skinless chicken breast
- Skinless turkey cutlets
- Pork loin
- Pork tenderloin
- Round steaks
- Top sirloin
- White fish like cod or seabass
Plant-Based Proteins
Although many plant-based proteins still contain phosphorus, your body does not easily absorb phosphorus from plant foods. For example, whole grains are higher in phosphorus, but they are considered safe to include in kidney condition diets because you won’t digest all of the mineral.
Plant-based proteins also typically have lower levels of protein compared to animal-based proteins. Research shows that following a low-protein diet may help delay kidney failure caused by IgA nephropathy.
Plant-based proteins include:
- Legumes: Beans, chickpeas, lentils, peas
- Soy products: Tofu, tempeh, edamame
- Nuts and seeds: Almonds, chia seeds, hemp seeds
- Whole grains: Brown rice, bulgar, oats, quinoa
Fruits and Vegetables Low in Potassium
IgA nephropathy can make it difficult for your kidneys to remove potassium, a mineral and electrolyte, from your blood. Eventually, too much potassium can build up in your bloodstream, leading to heart and muscle issues. Choosing fruits and vegetables lower in potassium can help you avoid too-high potassium levels that stress damaged kidneys.
Fruits and vegetables that are low in potassium include:
- Berries: Blackberries, blueberries, cherries, cranberries, raspberries, strawberries
- Citrus fruits: Grapefruit, Mandarin oranges, tangerines
- Tree fruits: Apples, peaches, pears, plums, grapes
- Cruciferous vegetables: Asparagus, broccoli, cabbage, cauliflower, kale, radish
- Legumes: Peas, green beans, wax beans
- Peppers: Red and green bell peppers
- Other foods: Carrots, celery, cucumber, eggplant, onion, white mushrooms
Foods High in Omega-3 Fatty Acids
When you eat foods high in saturated and trans fats, these fats can build up in your kidneys. These fats can be difficult for your kidneys to remove if you have kidney damage from IgAN. However, foods with polyunsaturated fats—like omega-3 fatty acids—may help regulate blood pressure and cholesterol levels related to kidney diseases.
Limited research also shows that omega-3 fatty acids may help slow the progression of IgA nephropathy, reduce inflammation, and improve kidney function.
Foods high in omega-3 fatty acids include:
- Fatty fish: Salmon, herring, mackerel, tuna
- Nuts and seeds: Chia seeds, flaxseeds, soybeans, walnuts
- Plant oils: Canola oil, soybean oil, flaxseed oil
People with IgAN may want to limit foods high in sodium. Your doctor may also recommend limiting potassium and phosphorus based on your bloodwork and stage of kidney disease. If you have IgAN, these minerals can build up in your bloodstream and worsen the progression of kidney disease.
You may also want to avoid foods high in saturated and trans fats, which are more likely to cause high blood pressure and cholesterol in people with kidney issues.
Specific foods you may want to limit or avoid with IgAN include:
- High-sodium foods: Processed or pre-packaged baked goods, frozen meals and meats, salty snacks, canned soups, cured meats, condiments, gravies.
- High-potassium foods: Bananas, potatoes, spinach, avocados, bananas, tomatoes, apricots, and certain types of oranges.
- High-phosphorus foods: Red meat; poultry with the skin; full-fat yogurt, cheese, and milk; packaged deli meats; flavored drinks; processed foods with added phosphorus, phosphoric acid, disodium phosphate, and monosodium phosphate.
- Saturated and trans fats: Processed baked goods, fried foods, butter, margarine, fatty or processed meats, full-fat dairy, coconut oil, palm oil.
Do You Need To Avoid Gluten?
Some people with IgAN may also want to avoid foods that can act like antigens, or proteins that trigger an immune response. However, more research is needed. Dietary antigens can include high-protein foods, dairy, and gluten.
Gluten is the most common dietary antigen associated with IgAN, and a higher proportion of people with IgAN also have celiac disease, meaning they have a negative immune reaction to gluten. Gluten is found in wheat, barley, and rye foods like pasta, bread, and crackers.
If you have IgAN, eating gluten may trigger your body to produce more antibodies that harm your kidneys. However, it’s unclear if a gluten-free diet slows the progression of IgAN, and further research is needed. Talk to your doctor to determine if a gluten-free diet is right for you.
Below are some kidney-friendly meal ideas for people with IgA nephropathy. Before starting any new meal plan, it’s important to check with your doctor first to ensure you are eating the best foods for you based on your kidney function and stage of kidney disease.
Breakfast
Start your day with a meal high in antioxidants and protein:
- Oatmeal with berries and walnuts: Whole grains like oatmeal are low in sodium and protein. While whole grains are a source of phosphorus, they may still fit in a kidney disease diet because not all of the phosphorus from plant-based foods is absorbed during digestion. Blueberries offer antioxidants, and unsalted walnuts are high in omega-3s.
- Egg white omelet: Egg whites are lower in phosphorus compared to egg yolks. Adding bell peppers and onions increases the antioxidant content without excessive potassium.
- Tofu veggie scramble: Crumbling tofu with vegetables like white mushrooms, onion, and peppers offers a low-phosphorus meal. Add a side of whole wheat toast for more whole grains.
Lunch
Refuel during the day with lean proteins and vegetables:
- Grilled chicken berry salad: Fill up on low-phosphorus chicken breast and antioxidant-rich onions, strawberries, and unsalted pecans. Create a simple, low-sodium vinaigrette with red wine vinegar and a bit of olive oil for healthy fats.
- Tuna salad: Combine low-sodium, water-packed tuna with low-fat Greek yogurt, onion, celery, herbs, lemon juice, and Dijon mustard for a low-sodium protein with omega-3s. Serve this on wheat bread or, for a gluten-free option, salad greens.
- Vegetable lentil soup: Mix low-sodium broth, lentils, herbs, kale, beans, carrots, celery, and onions for a filling, low-potassium, and plant-based protein meal.
Dinner
For dinner, try a lean animal or plant-based protein with a serving of vegetables:
- Baked salmon with broccoli: Salmon is a lean protein that is low in phosphorus and high in omega-3s. A side of roasted broccoli is low in potassium and offers antioxidants.
- Tofu and vegetable stir-fry: Tofu offers a low-phosphorus protein, while carrots, onions, peppers, and white mushrooms are low in potassium. A low-sodium soy sauce or seasoning limits sodium while adding flavor.
- Grain bowl: Try pearled barley for a lower-phosphorus grain. Roasted broccoli, onions, and bell peppers add antioxidants without too much potassium.
Because dietary needs depend on your kidney function and stage of disease, talk with your doctor or a registered dietitian before making significant changes to your eating plan. Considerations to discuss with them include:
- Building balanced meals: Focus on creating meals around whole foods rich in antioxidants and omega-3s.
- Choosing lean proteins, but in moderation: Since protein and phosphorus needs vary, manage your portion sizes with guidance from your doctor.
- Potentially limiting foods high in sodium, potassium, and phosphorus: Your kidneys may struggle to filter these minerals from your blood, leading to further strain and damage.
