Oxalate is an antinutrient found in certain leafy greens, vegetables, and animal foods. But, high oxalate levels can cause kidney stones and other health problems.
So, how do you prevent high oxalate levels in your blood? What foods should you avoid consuming? This article explores the foods rich in oxalate, how to prevent oxalate build-up, and possible side effects. Keep reading!
In This Article
The Science Of Oxalate
Oxalic acid in plants, when bound to minerals, forms oxalate. Your body can also produce oxalate on its own or get it from food. Vitamin C also can get converted into oxalate on getting metabolized (1).
When consumed, this oxalate can bind to minerals in the body and form compounds, including calcium oxalate and iron oxalate (2). Though it primarily happens in the colon, this process can also take place in the kidneys or the urinary tract.
Most people can excrete these compounds through stool or urine. But certain sensitive individuals may develop kidney stones and other health issues upon consuming high-oxalate foods.
The first step to avoid such issues is steering clear of foods rich in oxalates.
What Are The Foods High In Oxalates?
Following are the foods high in oxalates (3):
|Spinach||755 mg per ½ cup serving|
|Rhubarb||541 mg per ½ cup serving|
|Almonds||122 mg per 22 kernels|
|Beets/Beet greens||76 mg per ½ cup serving|
|Soy flour or soy protein isolate||27–94 mg per 1 oz serving|
|Wheat bran||34 mg per ¾ cup serving|
|Oranges||29 mg per fruit|
|Sweet potatoes||28 mg per 1 cup serving|
|Beans||10–25 mg per ½ cup serving|
|Berries||10–25 mg per ½ cup serving|
|Tea, brewed||14 mg per 1 cup serving|
|Beer||5–10 mg for every 12 fluid ounces|
|Tofu||13 mg per 3.5 oz serving|
Research tells us to limit our daily oxalate intake to less than 100 mg (or even 50 mg) (4).
People with a history of kidney stones or those who have the issue currently must stay away from these foods. Oxalate may bind with calcium in the blood and form calcium oxalate crystals, leading to stones. There are different types of kidney stones, but calcium oxalate is the most common of them.
These stones are not formed by calcium through food. In fact, excess calcium that isn’t used by your bones and muscles goes to your kidneys and is flushed out through urine. But when this doesn’t happen, the extra calcium stays in the kidneys and forms stones (5).
But there is good news. You can prevent this. Here’s how!
How To Prevent High Blood Oxalate Levels
A few simple diet and lifestyle changes can help in cutting down the risk of formation of oxalate stones in your body.
- Cut down on high-oxalate foods. We have already discussed this. Reduce your intake of foods high in oxalates. You don’t have to stop consuming these foods (unless your doctor advises otherwise) because most of them are quite healthy and replete with nutrients and antioxidants.
- Increase your calcium intake. This may sound contrary to the obvious logic. But yes, low calcium levels in your body can actually increase the risk of oxalate stones. This is because calcium binds with oxalate in the intestines. A high-calcium diet can reduce the amount of oxalate being absorbed in the body. This reduces the risk of stones (6).
- Drink enough fluids. This is a no-brainer. You must drink at least 4 to 5 liters of water every day – in addition to other fluids. Drinking enough water helps flush out calcium (and other minerals that may possibly form stones) and helps prevent the formation of oxalate stones (7).
- Avoid excess vitamin C. Oxalate is an end product of vitamin C metabolism. Excessively high doses of vitamin C can lead to the formation of oxalate stones (8). Stick to less than 500 mg of vitamin C daily – especially if you take supplements.
- Avoid excess protein. Consume optimal amounts of protein. Don’t go overboard. Excess protein intake has also been linked to oxalate stones (9).
- Cut down on sodium. This includes processed foods like hot dogs, sausages, burgers, canned products, pickles, and other convenience mixes. A high-sodium diet can trigger kidney stones as it increases the amount of calcium in your urine (10).
In addition to these measures, you can also include low-oxalate foods in your diet.
What Are The Foods Low In Oxalates?
Low-oxalate foods include the following:
|Bananas||3 mg per 1 fruit|
|Cherries||3 mg per 1 cup serving|
|Grapes||1 mg per 1 cup serving|
|Papaya||1 mg per 1 medium fruit|
|Watermelon||1 mg per 1 slice|
|Cucumber||1 mg per ¼ serving|
|Cauliflower||1 mg per ½ cup serving cooked|
|Mushrooms||Less than 1 mg per mushroom|
|Cabbage||1 mg per 1 cup serving, raw|
|Peas||1 mg per ½ cup serving|
|Cheese||Less than 1 mg per slice|
|Milk||1 mg per 1 cup serving|
|Lean meats||Less than 1 mg per 1 oz serving|
|Corn||1 mg per ½ cup serving|
|White rice||4 mg per 1 cup serving, cooked|
|Honey||Less than 1 mg in 1 tablespoon serving|
Including these foods in your diet can help. There are other reasons you must prevent oxalate build-up in your body. We will look at them now.
What Are The Other Side Effects Of Excess Oxalate Build-Up?
Oxalates can also hinder nutrient absorption. We already saw the case with calcium. Oxalates can hinder calcium absorption and lead to other complications, apart from increasing the risk of stone formation (11).
Consuming fiber along with oxalates can hinder the absorption of other nutrients like zinc and magnesium (12).
Oxalates may also contribute to vulvodynia, a condition characterized by unexplained chronic vaginal pain (13). The role of oxalates instigating this specific condition is doubtful, though.
Oxalates are naturally occurring molecules and are considered antinutrients. They are mostly found in humans and plants. However, excess oxalates in the body may cause kidney stones, chronic vaginal pain, and other health problems. While foods like spinach, rhubarb, almonds, beets, and soy flour are rich in oxalates, bananas, cherries, grapes, and papaya are low in them. You can prevent high blood oxalate levels by reducing the intake of foods high in oxalates, increasing your calcium intake, and drinking enough fluids. Keep checking your oxalate intake to avoid its adverse reactions.
Taking these measures can help in preventing the development of oxalate stones.
Anything you think we have missed in this post? Do tell us by leaving a comment in the box below.
Frequently Asked Questions
Can oxalates cause inflammation?
Yes. High levels of oxalates can cause inflammation (14).
Are eggs high in oxalates?
No. Eggs are low in oxalates.
Is coffee high in oxalates?
Yes. Coffee is high in oxalates.
Does lemon juice get rid of oxalates?
Do oxalates cause joint pain?
Yes. Oxalates may cause joint pain.
Can oxalates cause eye problems?
Yes. Oxalates can cause eye problems.
- The antinutrient oxalate is present in certain leafy greens, vegetables, and animal products.
- As oxalate binds with minerals in the body, it may develop kidney stones and other health problems.
- High oxalate foods include spinach, rhubarb, and almonds, so reducing their intake and drinking a lot of fluids can prevent high blood levels of oxalate.
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- “What are kidney stones?” National Institute of Diabetes and Digestive and Kidney Diseases.
- “Preventing kidney stones” National Center for Biotechnology Information.
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- “Hypocitraturia: Pathophysiology and Medical Management” US National Library of Medicine.
- “Evidence for abnormal linkage between urine oxalate and citrate excretion in human kidney stone formers” The Physiological Society.