Oxalate <25 mg/serving
Oxalate 25-99 mg/serving
Oxalate ≥100 mg/serving
Blueberries sit right on the edge between Safe and Caution territory — 27 mg oxalate per cup, just 2 mg above the 25 mg safe threshold. This makes them one of the most interesting foods in the Harvard database: not dangerous enough to avoid, not low enough to ignore. For most kidney stone patients, a half-cup of blueberries (about 14 mg) on oatmeal or yogurt is completely fine. A full cup every single day could push your daily oxalate total higher than you realize — especially if you combine them with other moderate-oxalate foods like whole wheat toast or sweet potatoes. Blueberries aren't a problem food — they're a portion-awareness food. Pair them with yogurt or milk for calcium binding, and watch your portion size.
📊 Nutrition at a Glance
How the form changes the number: preparation is the real variable across this family. Boiling leaches a meaningful share of soluble oxalate into the cooking water — commonly 30-50% for plant foods — while raw and dry-heat forms keep essentially all of it, so the same base food can land in different brackets depending on how it is cooked. This page tracks Blueberries (Fresh or frozen) at 27 mg per serving, at the high end of the family. Related forms in this family: Blueberries (Dried) (2 mg).
📏 Oxalate by Serving Size
| Serving | Weight | Oxalate | Verdict |
|---|---|---|---|
| 1 cup | 200 g | 27 mg | Moderate Oxalate |
| 2 x 1 cup | 400 g | 54 mg | Moderate Oxalate |
| ½ x 1 cup | 100 g | 13.5 mg | Low Oxalate |
🏷️ Tags
🟡 See all Fruits rated Caution for kidney stones →
🔗 Related Foods
🟢 Safe alternatives (recommended)
⚠️ Other foods in this category to watch
❓ Frequently Asked Questions
Should I avoid Blueberries if I have kidney stones?
Yellow zone. 27 mg per 1 cup means Blueberries sits in that middle ground where it's manageable but not risk-free. Half portions help. So does eating it less often.
What's the oxalate content of Blueberries?
Quick math: 1 cup of Blueberries = 27 mg oxalate. 100g = 14 mg. Both numbers come from Harvard's latest lab measurements. Not AI, not a database, actual lab work.
Is Blueberries high in oxalates?
Moderate. Blueberries has 27 mg oxalate per 1 cup — not high enough to panic, not low enough to ignore. Portions matter with this one.
What are the best low-oxalate alternatives to Blueberries?
Substitutes exist. The safe alternatives listed below are all low-oxalate foods in the same family as Blueberries. Grab one of those and you dodge the oxalate while keeping similar flavors.
How much Blueberries is safe to eat?
Think garnish, not main dish. Blueberries at 27 mg per 1 cup is a lot for one food. Use smaller amounts spread across meals or as a flavor accent rather than the centerpiece.
How much sodium does Blueberries have?
Low sodium: 2 mg/100g. That's a non-issue for kidney stones. Just don't undo it by drowning it in salt during cooking.