Is Kale Your Friend or Foe?


Written by Edith Cragg, School of Health & Wellness Faculty Researcher at the NewEarth University

You may not think that many of the green and leafy vegetables that form a big part of a “healthy diet” could actually do you more harm than good! Yet, if you are suffering from chronic pain or inflammation, this could be entirely blamed on natural chemicals called oxalates, which are contained in these so-called “healthy foods”. Oxalates cannot be seen, tasted or smelled, yet we consume them almost every day and luckily for the majority of the population, it doesn’t cause any issues.

However, these chemicals are found in certain “healthy foods” and whether they are your foe or friend depends entirely on the state of your gut.

What are oxalates? How can they harm us and which “healthy vegetables” contain high concentration of oxalates?

Vegetables high in oxalates:

broccoli, brussels sprouts, carrots, celery, okra, olives, parsley and spinach

Moderately high in oxalates:

artichokes, leeks, red potatoes and string beans

Low in oxalates:

kale, mustard greens, and collard greens

Oxalates are chemical compounds that are found naturally in our bodies, as well as in many plants, fruits, and essentially all nuts and seeds. Typically a healthy gut doesn’t absorb much of these particular chemicals from your diet, since oxalates are usually well metabolized by the good bacteria in your gut (provided you have them) and then are eliminated in your stool. However, when oxalates meet up with damaged tissues in your digestive tract, they bind with calcium and iron and crystallize — unfortunately leading to irritation and eventually pain.

Oxalates can also be described as a type of anti-nutrient, which have the effect to block the absorption or iron and calcium. They do this by forming complexes with these minerals, which in turn leads these oxalates to bind themselves to calcium and iron, only later to be excreted into the urine. This in turn can cause calcium oxalate stones being formed in the urinary system, leading to the painful diagnosis of kidney stones

If you have a gut populated with the right friendly bacteria, then these healthy foods should not cause you any issues, because your gut does not absorb much of these chemicals contained in your “healthy diet” as your body digests these foods. Once again, your “friendly gut bacteria” like lactobacillus normally metabolize these oxalates. If your gut is a happy gut, containing many good and healthy bacteria then there is nothing to worry about, since the oxalates will be eliminated naturally via your stool.

Painful issues can only arise due to damaged gut flora (bacteria) when the oxalates combined with the calcium form crystals and they come into contact with damaged tissue (think leaky gut). The result is irritation and inflammation, leading to painful episodes for the sufferer. This is especially the case for people who have leaky gut, where excess oxalates are then absorbed into your blood stream via the tight junctions in your digestive tract. This has been directly linked to a wide range of diseases such as fibromyalgia, autism, ADHD, kidney stones, dyspareunia, osteoporosis, IBS, thyroid disease, cystic fibrosis, chronic fatigue syndrome, joint and muscle pains and many more.

With the rise of children diagnosed with autism, it has been shown that many of those on the autism spectrum suffer from sensitivity to oxalates in their diets, due mainly to their compromised gut bacteria. The same goes for anyone suffering from thyroid issues and basically many other diseases, which relates directly to one’s gut health. It is my personal belief that all disease originates in the gut and therefore a healthy micro-biome is absolutely mandatory, in order to successfully navigates the issues arising from oxalates and other toxins contained in many of the modern day foods.

In short, leaky gut and insufficient good/friendly gut bacteria leads to inflammation and eventually to disease. Addressing the restoration of diverse, healthy gut bacteria is absolutely paramount, because this will lead to literally “plugging up the holes” in the digestive tract, thus ending the suffering from inflammation and pain, restoring overall optimal health.

Researcher Susan Owens refers to an intriguing fact about oxalate absorption in the body: “A person, who has had a history of heavy or even recent antibiotic use, has an increased risk of dietary oxalate damage.” It is well known in functional medicine that a single course of antibiotics can destroy the beneficial bacteria in the digestive tract, leading to oxalate damage. It is therefore of utmost importance to restore these good/friendly bacteria with the introduction of fermented foods into the daily diet.

How to Reduce Oxalates

Ms. Owens confirmed that low-oxalate vegetable options are kale, mustard greens, and collard greens. Her research indicates that boiling or steaming any of these vegetables will significantly reduce their oxalate content. For example, kale that has been steamed has an oxalate content of 8.8 mg, whereas the same amount of boiled kale contains 4.9 mg. By boiling it you can reduce the oxalate by 40%.

According to the venerable Donna Gates of Body Ecology: “If you suspect that oxalates are a concern to you or someone you know, the good news is that it’s relatively easy to minimize these chemicals:

1. Improve gut health. First and foremost, without eliminating anything, make sure that your digestive tract is in great shape and that you have an inner ecosystem teeming with a variety of beneficial micro-flora. Add probiotic liquids or fermented foods to your diet and encourage colonies of oxalate-eating lactobacillus to thrive.

2. Address Candida overgrowth. Fermented foods increase healthy bacteria levels in the gut and can also reduce levels of harmful Candida yeast. If you have Candida overgrowth, you’re promoting an environment that will not be able to break down oxalates.

3. Try a calcium supplement. Consider adding a citrate-based calcium supplement (calcium citrate) to your daily routine. Oxalates have a tendency to bind to this and can then be eliminated.”

So if you or someone you know suffers from inflammation and pain, even though they are on a “healthy diet”, please think twice before you have some raw kale (or any of the raw vegetables mentioned earlier) in your super smoothie or in a healthy salad. I would humbly suggest checking out whether oxalates could actually be the culprits of your discomfort. As you can see from the information given above, it is not too difficult to combat this particular issue.

Wishing you very Happy and Healthy Days and Nights

Edith Cragg

CoolWellbeing Foundation


* Donna Gates’ website:

* Susan Owen’s website:


Leave a reply

Your email address will not be published. Required fields are marked *