Oxalate toxicity is not well known, and whilst its symptoms are painful and serious, its reversal can be straightforward 


Oxalate toxicity is under-recognised and under-diagnosed.  It can be caused by genetic factors, by yeast fungus infection, by diet, or by a combination.  Symptoms can include fatigue, poor sleep, joint and muscles aches and pains, brain fogs, eye pain, burning sensation, vulvar pain and kidney stones.  You are more at risk of it if you have a leaky gut and it may interfere with body systems causing anaemia, heart arrythmia, underactive thyroid, interstitial cystitis, osteoporosis, fibromyalgia or carpal tunnel syndrome.  One problem is that it is counter-intuitive, often being caused by a diet rich in leafy greens!  The toxicity can be reversed by gradually reducing your oxalate intake, moving a bit towards a healing carnivorous diet, though you may experience greater pain at first as the oxalate is eliminated from your system.

Her diet of leafy greens was actually part of the problem

This 70-year-old lady presented with fatigue, tremor, rigidity and slow movement; she had difficulty maintaining an erect standing posture, necessitating the use of a Zimmer frame.  She attended the neurology clinic but did not respond to Parkinson’s disease medication (Madopar) Her head MRI scan was normal.

She also had ongoing symptoms of watery or itchy eyes, sneezing attacks, excessive mucus production, frequent throat clearing, hoarseness, constipation, joint pain and stiffness, arthritis, muscle pain, a feeling of weakness, low weight, poor physical co-ordination, depression, and frequent or urgent urination.  This was suggestive of an upper respiratory tract candida infection.

Nutritional support gave some improvement – she reported having more mental energy, good facial expression and eye movements – but her spinal and limb muscles deteriorated.

Her shoulder girdle, limbs and joints had become increasingly sore and rigid.  The patient had an ongoing candida infection and went on a “healthy” high-oxalate diet (leafy greens, nuts and seeds.)  The combination of the infection and the diet resulted in a high oxalate level.

The story of this patient reflects that not every “healthy” diet is good for everyone.

In this article I will discuss Oxalate toxicity syndrome, a common but under-recognised and under-diagnosed condition – how it happens, the clinical features and the actions to take to keep the problem at bay.

High oxalate can be caused by genetic variants, diet (real healthy & western processed diet), by a yeast fungus infection or metabolic by-product of vitamin C.  Food high in oxalates include almonds, beetroot, chocolate, spinach, French fries, potatoes, soy products, black tea, instant coffee, leafy greens, rhubarb, lentils, strawberries and raspberries, Turmeric but not curcumin, whole wheat flour products, bran & other cereals.  Oxalate poisoning was recognised as long ago as 1850, and seen as a seasonal problem, prevalent in spring and summer when fresh green food is abundant.

Oxalates help the storage of calcium in plants but may be poisonous to humans, resulting in acute or more often chronic toxicity.  Oxalates circulate in the blood as oxalic acid, which can easily combine with calcium to form calcium oxalate crystals and kidney stones.

Oxalates can also accumulate in the body tissues causing inflammation, autoimmune diseases, interference with mitochondrial function and energy production, and can result in neurological damage.

This can result in the unexplained symptoms of fatigue, poor sleep, heart arrhythmia, joint and muscles pains similar to fibromyalgia, brain fogs, eye pain, burning urine (interstitial cystitis), vulvar pain and kidney stones.

Oxalates can damage the gut lining, and having a leaky gut allows absorption of more oxalates into the body to cause toxicity.

A green smoothie contains 20 times the oxalate you can safely take in a day! 

Pumpkin seeds, sunflower seeds and flax seeds are the safest to eat as they contain a lower quantity of oxalates.  Olives are high in oxalates, but olive oil is not.

Calcium has a special love for oxalates, forming calcium oxalate kidney stones.  This can result in groin pain and cloudy, smelly urine, often with blood.  It can also cause urgent or frequent urination.  Kidney stones cause severe intermittent renal colic.  It is also associated with recurrent urinary infection, which often presents with fever and chills.

To avoid oxalates kidney stones, you must drink adequate fluids to avoid dehydration and eat food low in oxalates or any food in moderation.

Oxalates can also accumulate in the heart, causing attacks of arrhythmia.  This is observed in those with high oxalates consumption – for example, those who eat almond bread and drink spinach smoothies on a regular basis.  This can be attributed to localised acidosis and potassium depletion.  These patients need rehydration and their minerals replenished, in particular potassium, calcium and magnesium.

Oxalates poisoning can also cause diaphragmatic hiccough, a symptom prevalent in chronic renal failure and terminally ill patients.

A green smoothie is 20 times what you can safely take in a day!  Potatoes and sweet potatoes are also high in oxalates when consumed in large quantities.  It would require a lot of vitamin B and minerals to process them.

Hyperoxaluria can be caused by an inherited disorder of the intestine

Hyperoxaluria (high level of oxalates in the urine) symptoms include pain when urinating.  Some patients presenting with hyperoxaluria are eating large amounts of food high in oxalates, so avoid these foodstuffs if you have enteric hyperoxaluria.

Primary hyperoxaluria is when your kidneys fail because the body can no longer eliminate the extra load of oxalates: they then stay in your bloodstream and are deposited in your eyes, bones, skin, muscles and blood vessels, resulting in multi-system problems.

Primary hyperoxaluria is a rare inherited condition, where the liver does not create enough of the enzyme that prevents overproduction of oxalates.   It cannot be eliminated through the kidneys and so the excess oxalate combines with calcium to create kidney stones and crystals, which can damage the kidney and cause kidney failure.

Eating a high quantity of oxalates increase your needs for certain vitamins (B6, but also B7 and B1) and minerals (calcium, magnesium, iron, zinc) to process it.  Oxalates also deplete calcium causing osteoporosis and iron resulting in anaemia, as well as other essential vitamins and minerals.

Oxalates also activate the immune system causing systemic inflammation, deplete glutathione the master antioxidant resulting in oxidative stress crisis, and interfere with hyaluronic acid necessary for a healthy connective tissues.

Oxalates can cause neurological symptoms, mast cell degranulation and histamine release, vulva pain, fibromyalgia carpal tunnel syndrome.  Increased calcium excretion can result in osteoporosis.  Oxalate is eliminated routinely in the management of autism.

In guarding against oxalates, you should also consider eliminating gluten, dairy, sugar and refined carbohydrates, as these can damage the gut lining and result in leaky gut.

Patients usually asymptomatic until they form kidney stones

Oxalates patients are usually asymptomatic until they form kidney stones, which cause a lot of pain when they start to move.  Patients may present earlier with body aches and pains and fibromyalgia or carpal tunnel syndrome.

The body starts dissolving the crystals, causing cellular damage and pain.  Once these crystals are back in circulation and then excreted in urine, the symptoms start to ease.  The process of breaking down and uploading the stored crystals can cause the same or even worse symptoms than when they were originally deposited.

Lemon juice contains citric acid, which helps to weaken the bonds of oxalate crystals and makes them easier to separate.  Half a cup of lemon juice a day will help your kidneys to release all of the oxalates.

High oxalates can be diagnosed by a urine test (24-hour urine sample) to check oxalate levels in urine.  Blood tests can check the gene that causes Dent disease.  And radiology (ultrasound x-ray, CT or MRI scans) can show Musculoskeletal inflammation and stones in the kidneys.

The supplements recommended for those struggling with oxalate poisoning are calcium citrate, potassium citrate, magnesium citrate and potassium carbonate.   The purpose of the calcium citrate is to help release oxalates from your tissues, so make sure it has not had vitamin D in it, because vitamin D encourages the absorption of oxalates.

High oxalate + leaky bowel = double the problem

You should particularly reduce your oxalate intake if you have a damaged gut lining, because your leaky bowel can absorb more oxalates, if you suffer from inflammatory, autoimmune disease or mineral depletion, or if you have thyroid disease (oxalate can bind to T3 and disturb thyroid function.)  Oxalates is also a problem for obese diabetics.

The carnivore diet is good for the body, which will start dissolving and eliminating oxalates when you switch from an oxalate-rich diet to a carnivore one.  This highlights the healing effect of animal food such as bone broth – particularly for people with chronic arthritis and other pain.

But you may end up having oxalate dumping symptoms if you remove oxalates too quickly.  This can result in yeast flare-ups, painful bowel movements, rashes or hives, sandy or grainy stool, pain with urination, irritability and moodiness.  So, try and reduce your oxalates gently – by 5 to 10% a week.

Good quality probiotics, like Oxalobacter formigenes, helps to break down oxalate.  Other useful bacteria include lactobacillus, Bifidobacterium and Bacteroides.  Courses of antibiotics can disrupt the normal gut flora leading to an accumulation of oxalates, so avoid antibiotics and eat organic food, as pesticides and herbicides can also disrupt the flora.  Avoid mega doses of vitamin C as this can increase the level of oxalates.

Boiling reduces oxalate content by a third, far more effectively than steaming.  You can also use a binder, such as activated charcoal, alongside calcium and magnesium citrate to bind oxalates in the gut.  High doses of good quality fish oil can reduce oxalates, while omega 6 increases it.

OXABROW and OXALATOR are free online apps, useful in helping people to plan their meals. OXABROW gives you the quantity of oxalate per serving, while OXALATOR categorises food oxalate content from low to high.

The best oxalate cleanse is simply to reduce your consumption gradually and wait.  Just be aware that, in the short term, you may have to go through a flareup of symptoms when the stored oxalate is released.

I hope that this helps, my friends, and, as always, if you have any questions or any experience of oxalate toxicity that you would be happy to share, please do so.  Your sharing may help others to recognise, treat and reverse their own toxicity.  Thank you.