The Low-Down on Oxalates


Oxalates are a simple, naturally occurring compound found in many plant foods, particularly vegetables.   Interestingly, oxalates are also naturally produced in our bodies. Although the role of these endogenously (made within us) produced oxalates is as yet unclear, they might function as natural chelators, substances that ferry harmful substances, such as metals, out of our bodies.

In most people, only a very small amount of the oxalates consumed from food are absorbed into the bloodstream from the gut. However, in people with intestinal dysbiosis (abnormal bacteria in the gut) or inflammation, either of which could lead to “leaky gut syndrome,” the rate of absorption of oxalates might rise from the normal level of 1 to 2 percent to as high as 40 to 50 percent. In this situation, these absorbed oxalates can create a number of problems. The most well-known problem is kidney stones, which arise when the excessive amount of oxalates binds with calcium in the blood.   In addition, excessive oxalate levels in the blood have been linked to painful inflammation, interference with the function of glutathione (sometimes called our master anti-oxidant), lipid peroxidation (linked with atherosclerosis), and painful joint deposits.

Other studies have shown that excessive levels of oxalates in the blood interfere with mitochondrial function and have been linked with such diverse diseases as fibromyalgia, interstitial cystitis and possibly the autistic spectrum of disorders. Clearly, in those with compromised gut function, painful chronic inflammatory conditions and possibly other types of inflammation, lessening the oxalate load in the diet may be a helpful intervention. Lowering the oxalate content hopefully will give the person more time to deal with the core issue, which is to heal the gut.   For those with normal gut function and little inflammation, oxalate consumption in the diet, within reason, seems not to be an issue.

One of the things we pride ourselves on at Dr. Cowan’s Garden is listening to and acting on the feedback from our customers. Our customers are well-informed, savvy consumers who know a lot about their own health needs.   Many of you, in this past year, have asked us to offer a low-oxalate greens powder.   The reason is fairly simple: For those unable to tolerate a high oxalate level in this diet, it is almost tragic and, in fact, counterproductive, to be forced to eat a low-vegetable. Luckily, as usual, nature offers us a solution.

Although many green vegetables do contain a fairly high level of oxalates, we found three whose oxalate levels are low.   These three greens are mustard greens, collard greens and lacinato (dino) kale. Luckily, all three are not only low in oxalates, they also are loaded with nutrition.   Collard greens, like other brassicas, have a high vitamin, mineral and phytochemical content. Mustard greens contain high levels of the cancer-fighting chemicals called sulforaphanes, also prevalent in the other cabbage-family plants.   In addition, the high sulfur level in mustard greens has been shown to neutralize the negative effects of oxalates, so even the small amount of oxalates they do contain will most likely be rendered harmless.  

In our Low-Oxalate Greens Powder, we take these three local, organically grown vegetables, blanch them (which further reduces the oxalate levels in the finished product) and dry them at low heat. They are then blended in an equal-part ratio packed into Miron jars.

We are proud to be able to meet the needs of all our customers by offering this nutritious blend of green vegetables, specifically designed for those seeking a low-oxalate vegetable addition to their diet.  

Tom Cowan, M.D.