How High-Oxalate Foods Affect the Kidneys

If you’ve ever had kidney stones (or known someone who has), then you know just how painful they can be. Kidney stones develop as a result of your urine containing an overabundance of substances such as calcium, uric acid and oxalate, all of which promote the formation of crystals. Alternatively, your urine can also lack these substances. Either way, this creates an ideal environment for kidney stones to form.

Early on, you may not notice any symptoms associated with kidney stones until they have moved to the ureter – the tube that connects the bladder and the kidneys. Once the stones have moved into the ureter you may have pain that fluctuates in intensity, including back, rib and abdominal/groin pain. You may also feel nauseous, vomit, and could develop fever and/or chills if a kidney infection is also present. You may also find that you are urinating more than usual, as well as notice pain during urination. If you notice any of these symptoms or find that they are worsening, Dr. Ali Ghahary suggests seeking medical attention as soon as possible – as in some cases, kidney stones may not pass through the urine and will actually require surgical removal.

Now you might be wondering what causes kidney stones to form in the first place. As mentioned, they form as the result of certain substances found in the urine; but there’s got to be something that causes those substances to form too, right? Well, you’d be correct.

One of the biggest culprits of kidney stones is diet. While oxalate foods generally aren’t an issue for most individuals, Dr. Ali Ghahary says that if you are prone to developing kidney stones then you should avoid high-oxalate foods as much as possible. Some examples of foods that are high in oxalates include spinach, beets, nuts, potato chips and French fries. You’ll also want to limit your intake of vitamin C. While vitamin C has many great health benefits, large doses of it can increase the oxalate in your urine. You should also increase your intake of water, as it can help dilute the substances in the urine.

You can find more information on this and other kidney-related conditions by visiting The Kidney Foundation of Canada at