Last Chance - Mother's Day Sale

Last chance - Mother's Day Sale

For moms, thyroid health matters. Save $25 on our thyroid test kit or self-pay membership using code MOMDAY.

Oxalates, Oxalate Dumping, and Your Thyroid

Learn about oxalates, how high levels can affect your body, and the phenomenon known as oxalate dumping.
Oxalates, Oxalate Dumping, and Your Thyroid
Last updated:
Medically Reviewed by:

In this article

From a young age, we're told how important it is to eat our vegetables. What they don't tell us, however, is that some vegetables are high in oxalates, substances that can be harmful if they build up in our bodies.

If you're not familiar with the concept of oxalates, don't know how oxalates affect the body, or you're wondering whether you need to worry about them in your diet, we have the answers.

What are oxalates?

Oxalates, also known as oxalic acid, are naturally occurring compounds found in certain plant foods. They can also be synthesized by the human body. The primary function of oxalates is to bind minerals, and they play a role in the formation of kidney stones.

Your GI tract absorbs oxalate from your foods. But, how much oxalate depends on the types of foods you eat.

Oxalate binds with minerals such as calcium and iron to form a solid compound, sometimes referred to as stone or crystals. These compounds are generally small and pass through your kidneys into your urine. When you urinate, these compounds exit your body.

What foods are high in oxalates?

As mentioned, oxalates are naturally found in foods including the following:

  • Spinach
  • Kale
  • Chard
  • Rhubarb
  • Almonds
  • Tofu
  • Cocoa powder
  • Rice bran
  • Raw hazelnuts

Foods high in oxalate can also contain compounds that can bind with iodine and affect its absorption. Iodine is one of the essential minerals required for making thyroid hormones. If your body doesn’t absorb enough, it can lead to iodine deficiency. Thus, potentially affecting thyroid function.

How does oxalate build up in your body?

Oxalate levels can build up in one of two ways: higher amounts of oxalates are absorbed in the GI tract or the body's ability to break down and eliminate oxalates is impaired. 

A 2020 study further explains what can cause oxalate to build up in your body:

  • Genetics. Although rare, those with primary hyperoxaluria (high oxalate levels in your urine) have a defect in specific enzymes that can cause an overproduction of oxalate.
  • Malabsorption issues. Those with a history of GI surgeries, inflammatory bowel disease, or malabsorption syndromes can increase oxalate uptake in the intestines. Researchers believe this is related to fat malabsorption, which can ultimately lower the amount of calcium available to bind to oxalate.
  • Changes in the gut microbiome. Individuals with inflammatory bowel diseases have low amounts of oxalate-degrading bacteria commonly found in the gut. This has been linked to increased oxalate absorption as your body can’t break it down.
  • Gut inflammation. When inflamed, oxalate can easily move between the cells of the GI tract and into your body. This is commonly referred to as a leaky gut.

Gut inflammation and microbiome alterations have been linked to triggering autoimmune disorders. Because of this, those with autoimmune disorders may be at a higher risk of oxalate buildup.

What happens if you have too much oxalate in your body?

In low amounts, oxalates usually won’t affect your body. However, high amounts may increase your risk of kidney stones.

Calcium oxalate compounds are the most common type of kidney stones. This occurs when oxalates, usually from dietary intake, bind with calcium in your body to form a solid “stone.” Normally, kidney stones are small, like a grain of sand, and easily pass through your kidneys, but sometimes they can’t. In these cases, kidney stones lead to pain and inflammation and can even prevent your kidney from functioning properly.

Calcium oxalate compounds are not only found in your kidneys; they have also been found in the thyroid. A 2019 study reported that almost 80% of autopsies they performed had calcium oxalate crystals in their thyroid.

A 2023 study reports that damaged thyroid cells release oxalate crystals. In turn, this can cause:

Both oxidative stress and inflammatory reactions have been linked to triggering autoimmune disorders like Hashimoto’s. Hashimoto’s affects your thyroid gland and is the number one cause of hypothyroidism (low thyroid hormone levels).

What is oxalate dumping?

"Oxalate dumping" is a condition that is thought to occur when you decrease your oxalate intake too quickly, causing the body to “dump” all your excess oxalate load. This rapid decrease causes symptoms such as:

The symptoms of oxalate dumping typically go away in a couple of days, up to several weeks.   

Since a build-up of oxalates may result in chronic inflammation, some believe those with an inflammatory-related condition like Crohn’s disease or rheumatoid arthritis may benefit from oxalate dumping. The thought is as your body gets rid of these symptoms and symptoms of your inflammatory-related condition will improve.

Keep in mind that the concept of oxalate dumping is based on anecdotal evidence. To date, there is no scientific evidence to support this concept.

How can I reduce oxalate buildup?

The good news is there are ways to reduce oxalate buildup that don't involve "dumping" and its associated symptoms. These include:

  • Decreasing oxalate intake. Slowly decreasing oxalate in your diet helps prevent symptoms of oxalate dumping. Working with a nutritionist is the best way to reduce your oxalate intake.
  • Increase calcium intake. Work with your healthcare provider to safely increase calcium intake through food sources or supplements. Higher calcium levels may help decrease oxalate absorption.
  • Stay hydrated. Drinking water helps move oxalates out of your body.
  • Watch your sugar intake. Those with high sugar intake may be at a greater risk for kidney stones.
  • Cook those vegetables. Cooking vegetables that are high in oxalate can help lower the oxalate content.


A note from Paloma Health

Following a low-oxalate diet may benefit those with hypothyroidism or Hashimoto’s. By reducing your oxalate intake, your body can properly absorb iodine, potentially improving your thyroid hormone production. In addition, low oxalate diets may decrease inflammation, prevent kidney stones, and help with weight loss.

Starting a low-oxalate diet may be trickier than you think. Oxalate-rich foods are healthy and, in some cases, have been shown to benefit those with autoimmune disorders. Like with most diets, it is about finding the right balance. Our nutritionists here at Paloma Health can help you find the right balance of oxalates without depleting other essential nutrients. Set up an appointment with one of them today.

Dealing with Hypothyroidism?  Video chat with a thyroid doctor

Get answers and treatments in minutes without leaving home - anytime. Consult with a U.S. board certified doctor who only treats hypothyroidism via high-quality video. Insurance accepted.


Bargagli M, Tio MC, Waikar SS, Ferraro PM. Dietary Oxalate Intake and Kidney Outcomes. Nutrients. 2020;12(9):2673. doi: 10.3390/nu12092673

National Institutes of Health. Office of Dietary Supplements - Iodine. Published 2017. Updated July 28. 2022. Accessed March 29, 2023.

Mu Q, Kirby J, Reilly CM, Luo XM. Leaky Gut As a Danger Signal for Autoimmune Diseases. Front Immunol. 2017;8:598. doi:10.3389/fimmu.2017.00598

Kidney Stones | NIDDK. National Institute of Diabetes and Digestive and Kidney Diseases. Published May 22, 2019. Accessed March 29, 2023.

Guerlain J, Perie S, Lefevre M, Perez J, Vandermeersch S, Jouanneau C, et al. Localization and characterization of thyroid microcalcifications: A histopathological study. PLoS One. 2019 Oct 24;14(10):e0224138. doi: 10.1371/journal.pone.0224138

Qi Q, Hu Y, Chen Y, Xu Y, Hao Z. Dietary Selenium Intake and Kidney Stones in Old Adults: an Analysis from NHANES 2011 to 2018. Biol Trace Elem Res. 2023;201(4):1588-1595. doi: 10.1007/s12011-022-03282-8

Green S. What is Oxalate Dumping? - Keto Science. Published May 27, 2021. Accessed March 29, 2023.

Share article:

Emilie White, PharmD

Clinical Pharmacist and Medical Blogger

Emilie White, PharmD is a clinical pharmacist with over a decade of providing direct patient care to those hospitalized. She received her Doctor of Pharmacy degree from Massachusetts College of Pharmacy and Health Sciences. After graduation, Emilie completed a postgraduate pharmacy residency at Bon Secours Memorial Regional Medical Center in Virginia. Her background includes caring for critical care, internal medicine, and surgical patients.

Read more

Is Paloma Right For Me?

Hypothyroidism is a long-term commitment and we’re committed to you. Schedule a free, no-obligation phone consultation with one of our intake specialists to find out more.

Schedule a call
thyroid hormone for hypothyroidism

Find out if Paloma is right for you. Schedule a free call with one of our health care advisors.

Schedule a Call