Oxalate <25 mg/serving
Oxalate 25-99 mg/serving
Oxalate ≥100 mg/serving
Rhubarb is the undisputed heavyweight champion of dietary oxalate: 1,293 mg per half-cup raw. That's not a typo. It's the single highest food in the Harvard database, with more oxalate per serving than spinach, beet greens, and almonds combined. Rhubarb pie is a cultural tradition in parts of the US and UK — if you eat it once a year, it won't give you a stone. If you grow rhubarb in your garden and eat it weekly throughout spring, that's a different conversation.
📊 Nutrition at a Glance
📏 Oxalate by Serving Size
| Serving | Weight | Oxalate | Verdict |
|---|---|---|---|
| 1 cup, diced | 122 g | 1293 mg | Avoid |
| 2 x 1 cup, diced | 244 g | 2586 mg | Avoid |
| ½ x 1 cup, diced | 61 g | 646.5 mg | Avoid |
🏷️ Tags
🔴 See all Fruits rated Avoid for kidney stones →
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🔗 Related Foods
🟢 Safe alternatives (recommended)
⚠️ Other foods in this category to watch
❓ Frequently Asked Questions
Can I eat Rhubarb with kidney stones?
It's on the avoid list for a reason. 1293 mg per 1 cup, diced means Rhubarb is high-oxalate territory. Not a 'never ever' food, but close to it. Save it for rare occasions and tiny portions.
What's the oxalate content of Rhubarb?
The lab result: 1293 mg per 1 cup, diced (122g serving). That's 1060 mg per 100g. Harvard's ion chromatography analysis, 2024. Not crowdsourced, not estimated.
Is Rhubarb low or high oxalate?
High. At 1293 mg per 1 cup, diced, Rhubarb is a high-oxalate food. Harvard's 2024 data puts this firmly in the avoid zone for stone formers.
What can I eat instead of Rhubarb?
Substitutes exist. The safe alternatives listed below are all low-oxalate foods in the same family as Rhubarb. Grab one of those and you dodge the oxalate while keeping similar flavors.
Can I eat Rhubarb if I pair it with dairy?
Yes, it helps. Calcium from food (yogurt, cheese, milk) binds oxalate in your gut so less reaches your kidneys. With Rhubarb, having dairy at the same meal is a smart move. Not supplements though — those work differently.
Does boiling Rhubarb reduce the oxalate?
Here's the cooking hack: boil Rhubarb, discard the water. That's where the dissolved oxalate goes. Expect roughly 30-50% reduction. Steaming is a distant second place.
How reliable is the data for Rhubarb?
Oxalate: very reliable (Harvard 2024 lab measurement). Other nutrients: still being matched to USDA data. The oxalate figure is what matters for a kidney stone decision, and that one's solid.