This information is here to help support you if you struggle with an oxalate intolerance. Not everyone will necessarily need to implement these changes.

Oxalate (Oxalic Acid) is a molecule widely found in plants but can also be found in the human body- either as a result of dietary sources or endogenous production.  Like glutamate, and when in excess, oxalates can be problematic and contribute to a long list of health issues.

Some Foods/Herbs Highest in Oxalate

  • Parsley
  • Sorrel
  • Lambs Quarters
  • Spinach
  • Rhubarb
  • Beets
  • Potatoes (including chips/french fries)
  • Nuts (including nut butters & many grain-free flours)
  • Okra
  • Soy
  • Chocolate
  • Berries
  • Beans
  • Buckwheat

Symptoms Associated with Oxalates

  • sandy stools (think having to wipe several times to remove grit)
  • pale/light-colored stools
  • oxalate crystals in diapers, eyes, genitals, etc.
  • vulvodynia
  • frequent urination
  • kidney stones
  • UTI’s
  • bloating
  • elevated yeast/candida


Testing for elevated oxalate levels can be relatively easy, and a common organic acids test (OAT) can give you a better idea if this may be a problem for you. See this post for more information on how you can order and interpret an organic acids test (OAT).  I do feel as though it is important to mention there seems to be a bit of discrepancy between an organic acid test and blood test results, and I believe we are still discovering the efficacy of testing.  After quite a bit of testing, we have personally chosen to go off of symptoms.

What Would Cause You To Be Sensitive To Oxalates?

Many with autism and underlying health issues are intolerant to dietary sources of oxalates due to underlying sources of inflammation, imbalances, and system impairments. Here are just a few reasons for this:

  • oxidative stress
  • lack of proper bile production
  • gene SNP’s
  • lack of vitamin K
  • glyphosate
  • certain supplements can increase
  • and so on…

Oxalate & Glutamate

However, I found the glutamate and oxalate connection rather interesting. Glutamate induces oxidative stress, which is an endogenous producer of oxalate and, therefore, can increase oxalate. Oxalates can also convert to glycine, which can inadvertently increase glutamate. While magnesium is good and can sit on the glutamate receptor, it must be higher than calcium levels. Leafy greens are necessary for vitamin K, magnesium, fiber fermentation, etc.  Many showing elevated oxalate levels in testing start to immediately and drastically eliminate high oxalate foods. This can be problematic for many reasons, not limited to oxalate dumping, but it might contribute to the problem by reducing vitamin K.  In my opinion, if you are struggling with oxalates, instead of strictly removing all oxalate-containing foods, you may want to choose leafy greens lower in oxalate and lower consumption of nuts and other high oxalate foods until you’re able to get a better handle on the underlying reasons for increased oxalate production. Additionally, bifidobacteria can also degrade oxalate, which often comes from the metabolism of oligosaccharides (found in asparagus, Jerusalem artichokes, bananas, & oats, to name a few).  Diversity in a whole-food diet is hugely important.

I’ve included a few quotes to help further explain this connection.

“Vitamin K is very important for GABA and glutamate balance as well, as it is needed for healthy calcium metabolism where it reacts with glutamate and calcium to deliver calcium to the bones and teeth, and it prevents accumulation of excess calcium which would contribute to cell death. Vitamin K is a fat-soluble vitamin; however, unlike other fat soluble vitamins, it is not stored in the body and must be consumed on a daily basis. Typically, vitamin K is produced when the friendly flora in our gut process leafy greens, but if dysbiosis is present or you’re not eating leafy greens, then vitamin K is not produced in sufficient numbers and deficiency may develop.
The pancreas uses Vitamin K abundantly for sugar regulation. In addition to the brain, the pancreas is also very vulnerable to the accumulation of excessive glutamate or other excitotoxins, which will further impair regulation of sugar. As we discussed previously, too much or too little insulin or glucose can both contribute to excess glutamate Therefore, keeping glutamate and GABA in balance is critical for the health of the pancreas and all its functions and the health of the pancreas is vital for maintaining the balance.”…/how-to-increase-gaba-and…/

“In this paper, I am proposing that a deficiency in Vitamin K causes unregulated calcium movement and deposition in the body of the autistic child, and that unregulated calcium is a cause of many of the symptoms associated with autism. I am also proposing that a Vitamin K deficiency is the cause of the calcium oxalate crystals found in many autistic children. Calcium, in tandem with the neurotransmitter glutamate, is essential to the functioning of the excitatory cells of the nervous system: once glutamate opens the neuronal cell’s calcium channel, calcium pours into the channel and triggers the neuron to fire. The concentration of glutamate within the nervous system is therefore carefully regulated by the nervous system (specifically the astrocytes, which can be negatively affected by mercury and by neurotoxins produced by Lyme spirochetes) because excess glutamate will keep the calcium channels open, allowing calcium to continue to enter, and excite, the neurons. Dr. Russell Blaylock, among others, has written extensively about the neurotoxicity associated with an excess of glutamate. However, I believe that unregulated calcium may play an unappreciated role in triggering the incessant neuronal firing and resultant cell death that are a hallmark of excess glutamate in the nervous system. If a child is unable to regulate calcium due to a Vitamin K deficiency, that child may display signs of glutamate toxicity and uncontrolled neuronal firing that manifest as the cluster of behavioral disorders called autism.

“A Vitamin K deficiency may be a contributing factor in the autistic child’s endogenous production of oxalic acid, which can bind to and immobilize calcium. If the renegade calcium is bound to oxalates it cannot make its way into the nervous system and cause damage. The human body seems to have a reason for producing oxalic acid: to control and manage calcium. It also has the means to dispose of it once the diet contains adequate Vitamin K again: the Vitamin K triggers carboxylation of bone proteins, which can then chelate the calcium from the crystals and put the calcium where it belongs. Meanwhile the oxalic acid will be disposed of, via secretion either through the kidney tubules or across the intestinal membrane. However, if the kidney tubules are not filtering well due to the presence of CaOx crystals, or if the intestines do not contain oxalate-degrading bacteria, then the oxalic acid will remain in the body and re-crystallize. Disposal of any other waste product or toxin will be compromised also.” “Vitamin K appears to be capable of chelating the calcium from calcium oxalate crystals, thus dissolving them and opening up the kidney tubules as another avenue for disposal of soluble oxalate. As CaOx crystals deposited around the body begin to dissolve, the autistic child’s behavior should improve.”

Dr. Clive Solomons found that, if the diet is very low in oxalates, the dieter would begin to produce oxalates endogenously. The very-low-oxalate dieter is by definition eating few or no leafy greens, the main dietary source of Vitamin K1, lending some credence to the hypothesis that a Vitamin K deficiency is one reason the liver would manufacture soluble oxalates.”

Looking for more information on oxalates?

Great Plains Oxalate Link

Low Oxalate Diet

There is a good Facebook Group, Trying Low Oxalate Diet.