Oxalates: What are they, and how might they be impacting your health?

Oxalic acid is naturally found in nuts and many fruits and vegetables. During cooking or in the digestive tract, oxalic acid binds with minerals, forming oxalates such as sodium oxalate, potassium oxalate, magnesium oxalate and calcium oxalate.

According to Sally Norton, who is considered the oxalate expert in the health consulting space, the problems with this process are many:

• It can steal these minerals from the diet and the body, making them useless, which results in nutrient deficiency, growth and reproductive problems.
• Oxalate crystals are corrosive and can become very needle-like, damaging the gut lining and other organ tissues. Symptoms include rashes, joint pain and gastrointestinal issues.  Kidney stones are most often comprised of oxalates.
• The body has no way to metabolise oxalate and must excrete it, which can overwhelm the kidneys.

Unfortunately, many wholefood ketogenic diet plans are extremely high in oxalates (eg from spinach, almond flour, chia seeds, cacao and turmeric).

Sally says that a deficiency in vitamin B6 or high doses of vitamin C intake can result in higher production of oxalate in the body.

In summary, high consumption can result in many health problems. Oxalate damage is not an allergy or sensitivity problem but rather a toxicity problem. To prevent health problems associated with oxalate, people need to avoid foods high in oxalic acid and ensure adequate intake of vitamin B6 and biotin.

If you believe you have issues with oxalate toxicity, I would suggest visiting Sally Norton’s website.

Update October 2023: See also Sally’s book: Toxic Superfoods: How Oxalate Overload Is Making You Sick—and How to Get Better

For a list of studies on the topic, search for “oxalate” on my Nutrition research page.

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