Your kidneys are organs that play several important roles in your health. They help filter your blood, remove waste products, produce hormones, keep your bones strong, regulate fluid balance, and regulate your blood pressure.
Unfortunately, your kidneys can get damaged and become less efficient over time. This is commonly called kidney disease, and it affects around 10% of adults globally (1Trusted Source).
Various factors and health conditions, including diabetes, can raise your risk of kidney disease.
Prolonged high blood sugar levels may damage your blood vessels, including those in your kidneys. As a result, about 1 in 3 adults with diabetes also have kidney disease.
Dietary guidelines for kidney disease and diabetes vary based on the stage of kidney disease. The goal is to prevent the buildup of various chemicals, nutrients, and waste products in the blood in order to preserve kidney function.
People with kidney disease and diabetes should monitor their intake of sugar and the minerals sodium, potassium, and phosphorus.
Generally, people with kidney disease should consume no more than 2,000 mg each of sodium and potassium per day and no more than 800–1,000 mg of phosphorus per day.
In comparison, people with healthy kidneys can have up to 4,700 mg of potassium, 2,300 mg of sodium, and 1,250 mg of phosphorus per day.
People with kidney disease should also monitor their protein intake, since the kidneys may struggle to filter waste products from protein metabolism. On the other hand, people with end stage kidney disease may need more protein (5Trusted Source, 6Trusted Source).
Nutritional needs for people with kidney disease vary depending on how severe the disease is. Your healthcare provider and a registered dietitian can advise you on your individual needs for protein and other nutrients.
Here are 5 foods to avoid if you have kidney disease and diabetes.
Processed meats are made by drying, salting, curing, or smoking meats to enhance their flavor, texture, and shelf life. Bacon, deli meats, sausage, and jerky are some common types of processed meats.
Because processed meats are typically salted, they have a high sodium content. For example, a standard 3-ounce (85-gram) serving of bacon contains a whopping 1,430 mg of sodium, which is nearly 75% of your daily sodium allowance with kidney disease (7Trusted Source).
High sodium foods are not ideal for people with kidney disease and diabetes because excess sodium can significantly strain the kidneys. This may raise your blood pressure and cause fluid buildup in places such as your ankles and around your heart and lungs (8Trusted Source, 9Trusted Source).
Instead of processed meats, choose lean, skinless cuts of meat — like chicken breast fillets — which contain less sodium. However, as with all protein-rich foods, eat them in moderation based on your stage of kidney disease.
2. Dark-colored sodas
Sodas, especially dark-colored varieties, are not ideal for people with kidney disease and diabetes.
Dark-colored sodas contain phosphorus, which is used to prevent discoloration, prolong shelf life, and add flavor. Most dark-colored sodas contain 90–180 mg of phosphorus per 12-ounce (355-mL) serving (10Trusted Source).
Although this may not seem like much compared with the daily upper limit, sodas contain a different type of phosphorus than is naturally found in foods. It isn’t bound to protein but instead appears in salt form, meaning it’s absorbed into your blood more easily (11Trusted Source, 12Trusted Source).
Healthy kidneys can easily remove excess phosphorus from your blood, but this isn’t the case when you have kidney disease.
Having high blood phosphorus levels for an extended period can raise your heart disease risk, weaken your bones, and increase your risk of early death (13Trusted Source).
Sodas and other sugar-sweetened drinks are also high in added sugar. This isn’t ideal for people who have diabetes, since their bodies can’t regulate blood sugar levels properly.
Having high blood sugar levels over a long period can damage your nerves, further damage your kidneys, and raise your risk of heart disease (14Trusted Source).
Instead of soda, choose a beverage that’s low in sugar and phosphorus, such as water, unsweetened tea, or sparkling water infused with sliced fruits or vegetables.
3. High potassium fruits
Generally, fruits are healthy and packed with vitamins and minerals. However, people with kidney disease and diabetes may need to limit their intake of certain fruits — mainly those high in sugar and the mineral potassium.
If you have kidney disease, your body can’t remove potassium properly, which can lead to increased blood potassium levels, also known as hyperkalemia. If left untreated, this condition can cause fatigue, muscle weakness, heart problems, and even death (15Trusted Source).
Fruits high in potassium include bananas, avocados, apricots, kiwifruit, and oranges.
For example, a standard avocado (201 grams) contains 975 mg of potassium, which is more than twice the potassium content of a medium banana (118 grams) and nearly half the advised daily potassium intake for people with kidney disease (16Trusted Source, 17Trusted Source).
Fortunately, there are plenty of healthy low potassium fruits you can add to your diet in moderation as long as you monitor your carb intake. Grapes, berries, pineapple, mango, and apples are a few examples.
Dried fruits are made by removing water from fruit through various processes. This creates small, dense fruits rich in energy and nutrients.
Dried fruits aren’t ideal for people with kidney disease and diabetes because they’re high in sugar and minerals such as potassium.
In fact, just half a cup (65 grams) of dried apricots contains around 755 mg of potassium, which is roughly 38% of your daily potassium needs if you have kidney disease (18Trusted Source).
Also, dried fruits are high in fast-digesting sugar, which isn’t ideal if you have diabetes.
5. Most beans and lentils
In most cases, beans and lentils are considered healthy and convenient.
However, for people with kidney disease and diabetes, beans and lentils — both canned and fresh — are not ideal due to their relatively high phosphorus content. Canned versions are typically also high in sodium.
For example, 1 cup (185 grams) of canned lentils contains 633 mg of potassium and 309 mg of phosphorus. This is close to one-third of the daily advised amount for each of those nutrients for people with weak kidneys (19Trusted Source).
If you enjoy beans and lentils, you can still eat them in small amounts but not as a standard carbohydrate part of your meal.
If you choose canned beans and lentils, opt for a low sodium or “no salt added” version. Also, older research suggests that draining and rinsing canned foods can reduce their sodium content by as much as 33–80%, depending on the product (20Trusted Source).
