Oxalate <25 mg/serving
Oxalate 25-99 mg/serving
Oxalate ≥100 mg/serving
Coffee is one of the most pleasant surprises for kidney stone patients. Black coffee contains just 1-2 mg of oxalate per cup — essentially negligible. Some epidemiological studies even hint at a mild protective effect, possibly because coffee acts as a mild diuretic that increases urine output. The caffeine concern is real but separate from oxalate: caffeine slightly increases urinary calcium excretion, but at 1-3 cups per day the net effect appears neutral to slightly beneficial. What you put IN the coffee matters more than the coffee itself. Skip the chocolate syrups and mocha powders (both high in oxalate). A splash of milk or cream is actually helpful — the calcium binds oxalate from other foods in your meal. Black, with milk, or with a small amount of sugar: all fine. Just don't turn your coffee into a dessert.
📊 Nutrition at a Glance
📏 Oxalate by Serving Size
| Serving | Weight | Oxalate | Verdict |
|---|---|---|---|
| 1 cup | 236 g | 2 mg | Safe |
| 2 x 1 cup | 472 g | 4 mg | Safe |
| ½ x 1 cup | 118 g | 1 mg | Safe |
🏷️ Tags
🟢 See all Beverages rated Safe for kidney stones →
🔗 Related Foods
🟢 Safe alternatives (recommended)
⚠️ Other foods in this category to watch
❓ Frequently Asked Questions
Can I eat Coffee with kidney stones?
It's fine. Coffee has 2 mg of oxalate per 1 cup. That's low enough that kidney stone patients don't really need to worry about it. Harvard did the measuring, not us.
What's the oxalate content of Coffee?
The exact figure: 2 mg of oxalate per 1 cup of Coffee. Works out to 1 mg/100g. This is the number kidney stone patients actually need. Harvard (2024) verified.
Is Coffee low or high oxalate?
Nope. Coffee is a low-oxalate food — just 2 mg per 1 cup. Well under the 25 mg cutoff. You're in the clear with this one.
What can I eat instead of Coffee?
Look at the 'Safe Alternatives' section right below this FAQ. Those foods are all under 25 mg oxalate per serving and in the same category as Coffee. Pick from those.
How much sodium does Coffee have?
37 mg sodium per 100g in Coffee. Well under the 460 mg threshold. One less thing on your kidney stone checklist.
Is Coffee a good drink for kidney stones?
For beverages, 2 mg oxalate per serving puts Coffee in the safe category. Most of your daily fluids should still be water. This one's an occasional drink, not your hydration strategy.