Is rhubarb high in oxalate?
Yes. Very high, 659 mg per 1/2 cup diced
Range 602 to 753 mg across 3 studies, 61 g serving
Lower-oxalate swap: Strawberries, grade A, about 3.4 mg per 1 cup.
Rhubarb is high in oxalate: about 659 mg per 1/2 cup diced, which is 1318% of the 50 mg a day many stone clinics aim for, or 659% of the 100 mg others allow.
If your doctor has put you on a low-oxalate diet, eat it with something high in calcium, like milk, yogurt or cheese. Calcium in the same meal binds oxalate in the gut, so less of it reaches your urine. How much calcium, and what if you don't eat dairy.
50 or 100 mg a day: which target is yours
Boiling and draining lowers oxalate, because the soluble part leaches into the water. Compare the raw and boiled rows below.
Why sources disagree on rhubarb
The 3 studies here run from 602 to 753 mg per 1/2 cup diced, measured between 1981 and 2002. Variety, growing conditions and lab method all move the number. Every one of them lands in grade E.
Where this number comes from
Each row is one published measurement, converted to a 61 g serving (1/2 cup diced). The grade and the range use the rows prepared the way the serving is eaten, and take the middle. How the grades work.
| Per serving | Per 100 g | Preparation | Source |
|---|---|---|---|
| 232 mg soluble only* | 380 mg | Raw (n=1) | Hönow R., Hesse A, 2002via Foods 2023;12:3201, Table 5 (CC BY 4.0) |
| 461 mg | 756.3 mg | boiled | Savage G.P., Vanhanen L., Mason S.M., Ross A.B, 2000via Foods 2023;12:3201, Table 5 (CC BY 4.0) |
| 602 mg | 986.7 mg | Raw | Savage G.P., Vanhanen L., Mason S.M., Ross A.B, 2000via Foods 2023;12:3201, Table 5 (CC BY 4.0) |
| 659 mg | 1080 mg | Raw (n=4) | Libert B.O, 1981via Foods 2023;12:3201, Table 5 (CC BY 4.0) |
| 753 mg | 1235 mg | Raw (n=2) | Hönow R., Hesse A, 2002via Foods 2023;12:3201, Table 5 (CC BY 4.0) |
* The study measured soluble oxalate only, which understates the total, so it's shown but doesn't set the grade.
By Oliver Silen · Data checked November 2, 2026 · Not medical advice