Is flaxseed high in oxalate?
A
No. Very low, <1 mg per 1 tbsp ground
One study at <1 mg, 7 g serving
0 mg50 mg = a day60 mg+
Flaxseed is low in oxalate: about <1 mg per 1 tbsp ground, which is 0% of the 50 mg a day many stone clinics aim for, or 0% of the 100 mg others allow.
50 or 100 mg a day: which target is yours
Where this number comes from
Each row is one published measurement, converted to a 7 g serving (1 tbsp ground). 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 |
|---|---|---|---|
| <1 mg | 2.86 mg | Ground | Harvard T.H, 2023 |
By Oliver Silen · Data checked November 2, 2026 · Not medical advice