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5 Worst Foods for Your Kidneys

It may be best to avoid these top foods to protect your kidneys.
FACT CHECKED BY Olivia Tarantino

The kidneys are the warriors of the human body: balancing fluids, electrolytes, and solutes to filter water and waste out of our blood to make about 1,500 milliliters (50 fluid ounces) of urine daily. This is handled by the one million functioning units of each kidney called the "nephrons" which include tubules, limbs, and other structures, along with the glomeruli, which produce ultrafiltrate.

Two chronic diseases that increase the risk of kidney disease are diabetes and hypertension (high blood pressure). Kidney disease is ultimately classified into four conditions: kidney stones, acute kidney injury, chronic kidney disease (CKD), or end-stage renal disease (ESRD). Limiting sodium and saturated fat intake are primary ways to reduce risk and/or manage diabetes and hypertension, which could be protective against developing kidney disease.

All this to say that the kidneys are a force to be reckoned with, but they also can be prone to damage if we don't take care of them with healthy behaviors, including what we eat. Here we discuss five of the top foods to shy away from to best protect your kidneys. Read on, and for more, don't miss The #1 Best Eating Habit for Kidney Disease, Says Science.

Processed meats

different deli meats and sausages
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Meats that have undergone processing, such as bacon, sausage, hot dogs, deli meat, and burger patties are a double threat to kidney health: they are likely high in sodium and animal-derived protein. Excess sodium intake beyond 2300 milligrams (mg) per day, on a regular basis, is conducive to a diet that may increase blood pressure, and this creates extra stress on the kidneys. It is also suggested in recent literature that more animal protein than plant protein in the diet may increase the rate of kidney disease progression.

Soups

chicken noodle soup
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Often regarded as a light lunch side or a way to calm a sore throat if experiencing cold or flu-like symptoms, soups are unfortunately laden in salt. Even if soups are homemade, they will often use beef, chicken, or vegetable stocks which register at over 800 milligrams of sodium per cup. There are reduced sodium and low sodium versions on the market, but most consumers find that the flavor is off and, well, could use more salt. You can try your luck at making a sodium-free stock of vegetable scraps, herbs, and spices to impart flavor to a soup base; however, it may be best to just steer clear of soups altogether.

Frozen pizza

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America's favorite non-dessert pie usually is made with the same layers: white bread crust, high sodium tomato sauce, high fat cheese, and processed meat like sausage or pepperoni. Turn over your next frozen pizza package and you may be astounded to find nutrition facts that are in the quadruple digits on sodium and exceed recommendations for saturated fat. Takeout or restaurant pizza isn't much better but could have some nutritional redeeming qualities if you are able to customize the order (e.g., meat-free, half the cheese, whole wheat crust, etc.).

RELATED: 12 Worst Frozen Pizzas to Stay Away From Right Now

Fried potatoes

french fries
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Potatoes are the nation's number one consumed vegetable. And the number one form in which it's consumed? Fried. Whether your preference is for French fries, hash browns, potato chips, or potato pancakes, these foods aren't doing your kidneys any favors. Deep-fried foods are best avoided to protect your heart and kidneys. Potatoes are also high in potassium, which is a mineral usually advised to keep tabs on if your kidneys are compromised and reach CKD stage 3A or later stages of kidney failure.

Soy sauce

Soy sauce
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Soy sauce, as well as its cousin tamari, are some of the highest sodium sauces available at the supermarket. These products have a shocking 950 milligrams of sodium per one-tablespoon serving, which is nearly 50 percent of the daily value (DV) for sodium. Soy sauce is classically used to impart an "umami" or savory flavor. See if there is a way in your recipe to substitute low-sodium ingredients like mushrooms, tomato paste, nutritional yeast, or a flavored vinegar, in place of soy sauce.

Molly Hembree, MS, RD, LD
Molly Hembree, MS, RD, LD, is a nationally recognized registered dietitian. Read more about Molly