Introduction
Oxalate or oxalic acid is a naturally-occurring compound that accumulates within the leaves, fruits, and seeds of plants.2,3,4 Reported oxalate levels differ widely due to biological variation, cultivar differences, harvest timing, growing conditions, and analytical methods.1,3,6 Foods such as spinach, rhubarb, and beets show particularly large variability in measured oxalate content, with published ranges spanning several hundred milligrams per 100 grams.1
Analytical approaches such as capillary electrophoresis and ion chromatography both reliably measure oxalate in high-oxalate foods, though ion chromatography performs better in samples with very low concentrations.5 Despite variability in exact values, there is broad agreement about which foods are consistently high in oxalate. Common high-oxalate foods include leafy greens, especially spinach, green cabbage, chard, rhubarb, beets, while many other foods contain comparatively low levels.2,4,7
High dietary levels of oxalic acid may promote urolith or bladder stone formation in herbivores like the guinea pig and tortoise.
Table
The following chart shows the oxalic acid content in 100 grams of selected raw foods.8
| Produce | Oxalic acid (g/100 g) |
| Parsley | 1.70 |
| Chives | 1.48 |
| Purslane | 1.31 |
| Cassava | 1.26 |
| Amaranth | 1.09 |
| Spinach | 0.97 |
| Beet leaves | 0.61 |
| Carrot | 0.50 |
| Radish | 0.48 |
| Collards | 0.45 |
| Brussels sprouts | 0.36 |
| Beans, snap | 0.36 |
| Lettuce | 0.33 |
| Watercress | 0.31 |
| Sweet potato | 0.24 |
| Chicory | 0.21 |
| Turnip | 0.21 |
| Eggplant | 0.19 |
| Celery | 0.19 |
| Broccoli | 0.19 |
| Cauliflower | 0.15 |
| Asparagus | 0.13 |
| Endive | 0.11 |
| Cabbage | 0.10 |
| Okra | 0.05 |
| Pea | 0.05 |
| Tomato | 0.05 |
| Turnip greens | 0.05 |
| Pepper | 0.04 |
| Kale | 0.02 |
| Cucumbers | 0.02 |
| Squash | 0.02 |
| Coriander (Cilantro) | 0.01 |
References
References
Attalla K, De S, Monga M. Oxalate content of food: a tangled web. Urology. 2014;84(3):555-60. doi: 10.1016/j.urology.2014.03.053. PMID: 25168533.
Bargagli M, Tio MC, Waikar SS, Ferraro PM. Dietary oxalate intake and kidney outcomes. Nutrients. 2020;12(9):2673. doi: 10.3390/nu12092673. PMID: 32887293; PMCID: PMC7551439.
Crivelli JJ, Wood KD, Assimos DG. Is it time to retire the low-oxalate diet? No! J Endourol. 2021;35(10):1435-1437. doi: 10.1089/end.2021.0576. PMID: 34409855; PMCID: PMC8575151.
Ferraro PM, Bargagli M, Trinchieri A, Gambaro G. Risk of kidney stones: Influence of dietary factors, dietary patterns, and vegetarian-vegan diets. Nutrients. 2020;12(3):779. doi: 10.3390/nu12030779. PMID: 32183500; PMCID: PMC7146511.
Holmes RP, Kennedy M. Estimation of the oxalate content of foods and daily oxalate intake. Kidney Int. 2000;57(4):1662-7. doi: 10.1046/j.1523-1755.2000.00010.x. PMID: 10760101.
Massey LK. Food oxalate: factors affecting measurement, biological variation, and bioavailability. J Am Diet Assoc. 2007;107(7):1191-4; quiz 1195-6. doi: 10.1016/j.jada.2007.04.007. PMID: 17604750.
Mitchell T, Kumar P, Reddy T, et al. Dietary oxalate and kidney stone formation. Am J Physiol Renal Physiol. 2019;316(3):F409-F413. doi: 10.1152/ajprenal.00373.2018. Epub 2018 Dec 19. PMID: 30566003; PMCID: PMC6459305.
United States Department of Agriculture. USDA database for oxalic acid content of selected vegetables. 1984. Available at https://app.knovel.com/kn/resources/kpUSDADOA3/toc?filter=table&kpromoter=marc. Accessed on November 18, 2025.
Further reading
Harvard TH. Chan School of Public Health. Nutrition Department’s File Download Site. Oxalate Table 2023. Available at https://share.google/GXKHY1STXAYR3sGs4. Accessed on November 17, 2025.
Oxalate.org web site. Available at https://oxalate.org/. Accessed on November 18, 2025.
Pollock C. Oxalate content of selected foods. Nov 18, 2025. LafeberVet web site. Available at https://lafeber.com/vet/oxalic-acid-content-of-selected-foods/