A reader was told by his doctor to reduce his intake of oxalic acid and asked about oxalic acid content in foods. This is what VRG Nutrition Advisor Reed Mangels, PhD, RD had to say:
Some soy products are high in oxalic acid. Others have lower levels. Generally, for people who avoid oxalic acid due to kidney stones, a food containing 10 milligrams or less of oxalic acid per serving is considered acceptable in limited amounts. Researchers in Iowa looked at how much oxalic acid was in a serving of tofu and found that the following brands had less than 10 milligrams of oxalic acid in a 3-ounce serving:
- Soy Deli
- White Wave
- Small Planet
Of all the brands they tested, only Soy Deli had more than 10 milligrams of oxalic acid per serving.
They also found that 1 cup of Pacific Soy and WestSoy Soymilk (the only brands they tested) had less than 10 milligrams of oxalic acid. Soy sauce was also found to be low in oxalic acid. General recommendations that I’ve seen for a low oxalic acid diet call for 2-3 servings daily of foods that have 2-10 milligrams of oxalic acid per serving. Foods falling into this category would be 3 ounces of tofu, 1 cup of Pacific Soy soymilk, 1 cup of WestSoy soymilk, 1 tablespoon of roasted soynuts, and 2 Tablespoons of soy nut butter (not low carb soy nut butter).
Soy foods that are too high in oxalic acid for many low oxalate diets are edamame, textured soy protein, and tempeh.
Speak with your doctor and dietitian concerning your upper limit of oxalic acid.
The reference for the study on oxalic acid in soy products is:
Al-Wahsh IA, Horner HT, Palmer RG, Reddy MB, Massey LK.
Oxalate and phytate of soy foods.
J Agric Food Chem. 2005 Jul 13; 53 ( 14 ): 5670-4 .
The USDA has published a table of the oxalic acid content of vegetables at:
This scientific article also has information about oxalic acid in some foods:
The Oxalosis and Hyperoxaluria foundation has published tables of oxalates in foods.
The contents of this blog, website, and our other publications, including Vegetarian Journal, are not intended to provide personal medical advice. Medical advice should be obtained from a qualified health professional. We often depend on product and ingredient information from company statements. It is impossible to be 100% sure about a statement, info can change, people have different views, and mistakes can be made. Please use your best judgment about whether a product is suitable for you. To be sure, do further research or confirmation on your own.
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