5 Things To Know About Oxalates and Thyroid Health

In 2017 I wrote a detailed article on oxalates.  One of the focuses of the article was how high oxalates are a risk factor for the development of kidney stones, although there was plenty of other information, including a list of some of the common foods higher in oxalates.  This past weekend I attended a conference on organic acids, and since oxalates were one of the topics discussed I figured it would be a good time to write an updated blog post on this.  While it won’t be as comprehensive as the article I wrote in 2017, there will be a few new things I discuss in this blog post.

So here are five things you should know about oxalates:

1. There are three main sources of oxalates.  The number one cause of elevated oxalates is eating foods high in oxalates.  Some of the foods high in oxalates include spinach, soy, nuts, beets, Swiss chard, raspberries, and blackberries.  If you test high for oxalates then the first thing you should do is evaluate your diet, and if you have been eating a lot of high oxalate foods then you should follow a low oxalate diet for a few months.

An overgrowth of fungi can also result in high oxalates.  This can include Candida albicans, other types of yeast, and mold.  A lot of people with thyroid and autoimmune thyroid conditions have an overgrowth of Candida.  If you have a Candida overgrowth and/or mold is responsible for elevated oxalate levels, then this obviously needs to be addressed in order to lower oxalates.

The third main source of high oxalates is cell metabolism.  In other words, your body will endogenously produce some oxalates, and certain genetic defects can increase the likelihood of you having high oxalates, even if you don’t eat high oxalate foods and/or don’t have a yeast or mold overgrowth.  But under normal conditions, and assuming you don’t have type 1 or 2 primary hyperoxaluria (I’ll discuss these conditions shortly) your oxalate levels shouldn’t be elevated.

2. In some cases oxalates can directly affect thyroid health.  I spoke about this previously in the article I wrote, as oxalate crystals can deposit in different areas of the body, including the thyroid gland.  And while I can’t say that oxalates are commonly detected on a thyroid ultrasound, the deposition of oxalates in the thyroid gland might be more common than we think.  This is backed up in the research, which confirms a high percentage of oxalate crystals in the thyroid glands of autopsied adults (1) (2).  And it’s not just adults that have high oxalates.  In fact, one of these studies showed 20% of human infants at autopsy were found to have oxalate crystals deposited in the thyroid gland.

In addition to the thyroid gland, oxalates can deposit in other areas of the body, including the following:

• Kidney
• Bone
• Brain
• Skin
• Nervous tissue

Depending on where the oxalates are deposited, this can lead to muscle and joint pain, and can even be a factor in some cases of fibromyalgia.  Although elevated oxalates don’t always result in pain, if you do have elevated oxalates that are resulting in muscle and/or joint pain, then it shouldn’t be a surprise that decreasing the oxalates should help to reduce the pain.  However, if you switch from a high oxalate diet to a low oxalate diet too quickly you can experience “oxalate dumping” symptoms.  In order to avoid these oxalate dumping symptoms you would want to slowly decrease the oxalates from your diet.

3. Organic acids testing can detect the presence of oxalates.  The urinary organic acids test from Great Plains Laboratory measures three specific oxalate metabolites.  This includes gylceric, glycolic, and oxalic.  The one most commonly high on an organic acids test is oxalic, but I’d like to briefly discuss the other two metabolites.

Glycolic relates to primary hyperoxaluria type 1, which is caused by a deficiency of the enzyme alanine glyoxylate aminotransferase (AGT).  This enzyme breaks down oxalates.  It’s important to keep in mind that AGT is dependent on vitamin B6, which means that if someone is deficient in vitamin B6 this can sometimes be a factor in high oxalates.  Some people with high oxalates can benefit from taking 100mg of vitamin B6 daily, although it might be a good idea to start with lower doses (i.e. 10 to 20mg per day) and then gradually increase.  Children with high oxalates might also require vitamin B6, but should take lower doses than adults.

High glyceric levels on an organic acids test usually relates to primary hyperoxaluria type 2.  In this condition there is a deficiency of glyoxylate reductase/hydroxypyruvate reductase (GRHFR).  Whereas primary hyperoxaluria type 1 can lead to kidney failure, primary hyperoxaluria type 2 is more likely to cause the formation of kidney stones.  Of course neither one of these conditions are good to have, and while there is a genetic component, you can support these conditions by making sure you have healthy vitamin B6 levels, and you also want to make sure you’re not eating a lot of high oxalate foods (you should eat between 40mg to 60mg of oxalates per day).

Earlier I mentioned that a Candida overgrowth and/or mold exposure can also cause an increase in oxalates.  The good news is that the organic acids test from Great Plains Laboratory not only tests for the oxalate metabolites, but also is a wonderful test for determining if someone has yeast and mold.  And while you can test for a Candida overgrowth in the stool and/or blood, I find the organic acids test to be more reliable.  In addition, the organic acids test not only looks at metabolites related to Candida, but other fungi that can produce oxalates.  For example, Aspergillus niger is a fungus that can lead to black mold, and the research shows that it can produce oxalates (3) (4).

4. Consuming calcium and magnesium citrate right before meals can help to prevent oxalate absorption.  The research shows that citrate inhibits the formation and growth of calcium crystals (5).  Since approximately 80% of stones are calcium based, it would seem counterproductive to take calcium, but supplementing with calcium can actually inhibit the intestinal absorption of oxalates (5).  If you choose to take a calcium supplement for high oxalates, 200 to 400mg of calcium citrate would be a good option (5).  Taking an equivalent amount of magnesium citrate also can be beneficial.

5. Cooking isn’t a solution for high oxalate foods.  Although cooking will reduce oxalates, it usually won’t lower the oxalates enough to safely consume high oxalate foods.  So for example, spinach is very high in oxalates, and while cooking spinach will reduce the amount of oxalates, it still won’t be low enough to consume if you are following a low oxalate diet.  So if you have high oxalates it really is a good idea to avoid all high oxalate foods.  Click here for a comprehensive list of foods that are low, moderate, and high in oxalates.  FYI, I got this list from the website of Great Plains Website, as Dr. William Shaw linked to it in an article he wrote on oxalates and autism.

Other Things You Should Know About Oxalates

Earlier when I was talking about vitamin B6 I mentioned how children shouldn’t take very high doses of this vitamin.  And while most of my patients are adults, it’s not uncommon for children to have high oxalates on an organic acids test.  This is especially true for those who are avoiding common allergens, such as gluten and casein.  The reason for this is because a lot of children and teenagers (and adults) who are gluten free will eat high amounts of foods with almonds, which are high in oxalates.  For example, someone who is gluten and dairy free might drink a lot of almond milk, eat almond butter, and frequently consume baked goods with almond flour.

And while I’m a big advocate of smoothies, if you’re not careful these can also be high in oxalates.  Spinach is very high in oxalates, and some people load up their smoothies with spinach.  I’m not suggesting that you should never eat spinach, as without question it has some good health benefits, but if you are adding a cup or two of spinach to your smoothie this is too much.  I personally add a lot of lettuce to my smoothie, as this is lower in oxalates.  Blackberries, blueberries, and raspberries are also high in oxalates, and while I do add these to my smoothies daily, I only add ¼ of a cup.  You also can add some calcium and magnesium citrate to your smoothie, as I mentioned earlier how this can help prevent oxalate absorption.

A few studies also mention that taking high dose probiotics can help with oxalates.  For example, VSL#3 is a high dose probiotic supplement, and a few studies have shown that taking VSL#3 can reduce gastrointestinal oxalate absorption, which in turn can decrease the risk of kidney stone formation and other conditions related to high oxalate levels (6) (7).

Action Steps To Take If You Have High Oxalates:

If you have tested high for oxalates on an organic acids test then I would recommend to take the following action steps:

Step #1: Gradually make the transition to a low oxalate diet

Step #2: If you tested high for fungi then address this

Step #3: Consider supplementing with vitamin B6

Step #4: Take calcium and magnesium citrate when consuming foods higher in oxalates (while gradually making the transition to a low oxalate diet)

Step #5: Consider taking high dose probiotics

So hopefully you learned a few new things about oxalates that you didn’t know before.  Eating foods high in oxalates is the number one reason for elevated oxalates, although having high levels of fungi can also cause this.  Supplementing with vitamin B6, high dose probiotics, and calcium/magnesium citrate can be beneficial for those who have high oxalate levels on an organic acids test.  While I don’t recommend an organic acids test to all of my patients, if you’re concerned that you have elevated oxalates then you might want to consider ordering such a panel.  If you are unable to obtain one from a local practitioner you can contact our office and order one.