Oxalate <25 mg/serving
Oxalate 25-99 mg/serving
Oxalate ≥100 mg/serving
Kale is the most confusing leafy green for kidney stone patients — and the confusion is understandable. On one hand, kale is a cruciferous vegetable (like broccoli and cabbage), and cruciferous vegetables are almost uniformly low in oxalate. On the other hand, kale looks and tastes like a leafy green, and leafy greens (spinach, chard, beet greens) are often high in oxalate. The data resolves the confusion: boiled kale has about 3 mg oxalate per half-cup — firmly safe. Raw kale is slightly higher (~8-10 mg per cup) but still safe. Unlike spinach, kale doesn't concentrate oxalate in its leaves. This makes kale the "safe leafy green" — all the nutrients and versatility of greens without the oxalate bomb. Boil it, sauté it, bake it into chips. Just don't confuse it with spinach, which is a completely different oxalate story.
📊 Nutrition at a Glance
📏 Oxalate by Serving Size
| Serving | Weight | Oxalate | Verdict |
|---|---|---|---|
| 1/2 cup cooked | 65 g | 3 mg | Safe |
| 2 x 1/2 cup cooked | 130 g | 6 mg | Safe |
| ½ x 1/2 cup cooked | 32 g | 1.5 mg | Safe |
🏷️ Tags
🟢 See all Vegetables rated Safe for kidney stones →
⚖️ Compare this food: · vs Soup · vs Chips →
🔗 Related Foods
🟢 Safe alternatives (recommended)
⚠️ Other foods in this category to watch
❓ Frequently Asked Questions
Should I avoid Kale if I have kidney stones?
Yep, you're good. Kale clocks in at 3 mg oxalate per 1/2 cup cooked — way under the 25 mg cutoff. Eat it without the stress. Measured by Harvard, not guessed.
What's the oxalate content of Kale?
The lab result: 3 mg per 1/2 cup cooked (65g serving). That's 5 mg per 100g. Harvard's ion chromatography analysis, 2024. Not crowdsourced, not estimated.
Is Kale high in oxalates?
It's low. 3 mg per 1/2 cup cooked is well under the 25 mg danger line. Kale is not the food you need to worry about.
What are the best low-oxalate alternatives to Kale?
Substitutes exist. The safe alternatives listed below are all low-oxalate foods in the same family as Kale. Grab one of those and you dodge the oxalate while keeping similar flavors.
How reliable is the data for Kale?
The oxalate number for Kale — 3 mg per serving — is from Harvard's 2024 lab analysis. That part is solid. The USDA nutrition data (sodium, protein, calcium) is still being matched — we'll update when it's available.