Foods To Avoid For Optimal Kidney Health

August 29, 2023

Individuals with a pre-existing kidney condition, such as chronic kidney disease, need to make sure they are doing everything possible to keep healthy. Diet can go quite a long way towards improving overall health, but did you know there are certain foods people shouldn't eat if they have kidney disease? If someone's kidney function is declining, it's even more important for them to keep on top of what they eat and drink, but starting with good habits early on will ensure a better quality of life.

Here are some of the most important foods to avoid for kidney health, as well as why it's vital for individuals to limit or eliminate them from their diet.

Dark Sodas

Dark-colored sodas have high levels of phosphorus, which can be harmful to kidney disease patients. While phosphorus is needed to help build healthy bones alongside vitamin D and calcium, those with kidney disease won't be able to process phosphorus efficiently to get the full benefits. This leads to phosphorus building up in the blood, which in turn can weaken bones and cause joint pain. If individuals still want a fizzy drink as an occasional treat, they may be able to drink some lighter sodas, as well as some lemonades. Patients should speak to their doctor and dietitian about whether or not they can safely include these in their diet.

Processed Meat

Individuals with kidney disease or poor kidney function should avoid processed meat, such as hot dogs, sausages, pepperoni, salami, lunch meat, and beef jerky, as these foods are high in protein, sodium, and preservatives. As most patients with kidney disease are recommended to keep their daily sodium intake to two thousand milligrams or less, eating processed meat can quickly take them over the limit. The higher levels of protein can also be harder for compromised kidneys to process. Instead of eating processed meat, individuals should choose portions of fresh, lean meat that fit the protein requirements their doctor or dietitian have set out for them.

Pickled Food

Pickled food, as well as relishes and olives, can be incredibly high in sodium. Consuming too much sodium forces kidneys to work harder to process it, which could lead to further kidney damage and decreased function. Even a small serving of pickled cucumbers could contain three hundred milligrams of sodium. Olives, for example, are often processed with sodium to improve taste and reduce a bitter taste, which means just a handful could add up to a significant portion of an individual's daily sodium allowance. While reduced-sodium pickles and relishes are commonly available, they can still contain fairly high levels of sodium and potassium, so it's important not to eat them too often.

Canned Food

Canned foods, such as vegetables and soups, are convenient and suit many busy lifestyles, but they often have high levels of sodium because of how they are processed. While lower-sodium versions are available at most grocery stores, individuals will still need to monitor their sodium intake carefully and limit their consumption because these are also high in potassium, which can be dangerous. Try making soups and stews from scratch using fresh herbs and spices to keep the sodium content down. Individuals can often freeze these for later and reheat them at their convenience. Canned vegetables and fish can be rinsed to remove some of the sodium, but the best bet is to eat fresh or frozen vegetables and fish instead.

High Sodium Condiments

High sodium condiments are more common than many might think. Even ketchup can have as much as 160 milligrams of sodium in a single tablespoon. Sauces commonly used in Asian cooking, such as soy sauce or teriyaki sauce, could have up to as much as 690 milligrams of sodium per tablespoon. Eating these sauces could very quickly take individuals over the safe limit of sodium, which could lead to further kidney damage. Instead of relying on condiments or sauces with a high level of sodium, try adding spices, fresh herbs, lemon juice, or black pepper to food.


Avocados are very healthy. They are full of vitamins, minerals, and phytochemicals, and they are also a very healthy source of fats. Unfortunately, they may not be so good for the kidneys. Avocados are very rich in potassium, which can be difficult for the kidneys to process. Individuals with kidney problems will most likely be told by their physicians to avoid too much potassium, so it's okay to say no to the guacamole once in a while. Typically, restrictive renal diets are low in sodium, potassium, protein, and phosphorus, all of which are difficult for kidneys to process. Even with healthy kidneys, diets high in these substances can lead to kidney disease later in life.

Too Much Dairy

Dairy has long-since been a controversial foodstuff. Some nutritionists tout it as being healthy and rich in protein and nutrients, while others may claim it can be bad for human health. Regardless of where an individual stands on the issue, dairy products, such as milk, contain quite a bit of phosphorus and potassium. As noted above, potassium can be difficult for our kidneys to process, and so can phosphorus. Patients with kidney disease especially will not be able to process large quantities of potassium and phosphorus, nor will they be able to process the excess protein found in dairy. A build-up of any of these nutrients in the blood can cause problems in the body's organ systems. A better alternative to dairy may be rice or nut milk.


Apricots are a culprit because they are also high in potassium. One cup of this fruit has about the same amount of potassium as a medium-sized banana, about 425 milligrams. While an avocado has more potassium, it's still best to avoid potassium-rich foods such as bananas and apricots as well. Too much potassium in an individual's blood can lead to hyperkalemia, which is a serious condition that can cause circulatory and digestive problems. This strengthens the point made earlier that individuals with kidney disease especially should avoid potassium-rich foods.

Normally, our intake of potassium should be 3,500 milligrams per day or more, which could help prevent high blood pressure, strokes, and osteoporosis. Unfortunately, kidney disease patients are unable to process the mineral, so their diets must be regulated to ensure they don't also develop hyperkalemia.

Sweet Potatoes

Another potassium-rich food, sweet potatoes can be bad for an individual's kidneys for the same reason dairy and the aforementioned fruits may be bad for them. Healthy kidneys can handle diets rich in phosphorus, protein, and potassium, but kidney health can be better maintained if these nutrients are eaten in moderation. Since individuals with kidney disease are put on special diets to restrict their intake of these nutrients, eating less can help individuals avoid kidney disease altogether. Foods like sweet potatoes are very nutritious, as are many of the foods already discussed on this list; however, partially avoiding risks that could potentially lead to renal failure may be wise considering the long-term consequences.

Certain Supplements

We already know potassium, phosphorus, and protein can potentially be harmful to our kidneys, which is why it's important to avoid foods rich in these nutrients. Individuals will also want to avoid high quantities of potassium, for instance, in the form of supplements. Other nutrients can cause problems as well, which is why individuals need to be careful when taking vitamins.

Certain supplements have been found to be harmful to kidneys, such as chromium picolinate, an herb known as willow bark, and pennyroyal, which is a herb used to help alleviate colds. Fat-soluble vitamins such as vitamin D can also be difficult on the kidneys. It's definitely important for patients to discuss supplements with a doctor.

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