Is sweet potato high in oxalate?
Yes. Very high, 70 mg per 1 medium sweet potato, baked
One study at 70 mg, 130 g serving
Lower-oxalate swap: Winter squash, grade A, about 4 mg per 1/2 cup cooked.
Sweet potato is high in oxalate: about 70 mg per 1 medium sweet potato, baked, which is 140% of the 50 mg a day many stone clinics aim for, or 70% 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
Why sources disagree on sweet potato
Lists disagree on sweet potato by about 9 times. Harvard measured it baked at 54 mg per 100 g, and a 2021 study measured it raw at 496. This page grades the baked value, since that's how it's eaten, and it's still more than a 50 mg day in one potato.
Where this number comes from
Each row is one published measurement, converted to a 130 g serving (1 medium sweet potato, baked). 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 |
|---|---|---|---|
| 0 mg soluble only* | 0 mg | Raw (n=3) | Santamaria P., Elia A., Serio F., Todaro E, 1999via Foods 2023;12:3201, Table 5 (CC BY 4.0) |
| 70 mg | 54.2 mg | Baked | Harvard T.H, 2023 |
| 644 mg | 495.6 mg | Raw (n=2) | Siener R., Seidler A., Hönow R, 2021via 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