How Much Oxalate Is in Flour?

Harvard's 2024 analysis found 197 mg of oxalate in one serving of Flour (1/4 cup). At the 100-gram level, that's 519 mg. This puts Flour in the Avoid range (100+ mg per serving). Keep in mind: oxalate varies by growing conditions, preparation method, and variety — but Harvard's measurement is the most reliable reference available.

✓ Medically Reviewed Based on Harvard T.H. Chan SPH oxalate data (2024) and NKF/AUA dietary guidelines.

197
mg oxalate
per serving

Food: Flour, Almond Meal, Trader Joe'ss
Serving: 1/4 cup (38 g)
Verdict: 🔴 Avoid
Per 100g: 519 mg
Data: Harvard T.H. Chan SPH (2024)

🔄 Lower-Oxalate Alternatives

💡 What This Means for Your Diet

What this means: Flour is rated Avoid (🔴). At 197 mg oxalate per serving, Flour exceeds the 100 mg threshold. Kidney stone patients should limit or avoid this food. If you do eat it, keep portions very small, pair it with calcium, and drink extra water. Check the full food page for safer alternatives.

📊 How Flour Compares

Among nuts & seeds, Flour sits well above the category average of 36 mg. For context, 29 out of 51 nuts & seeds (56%) are rated 🟢 Safe (under 25 mg oxalate/serving). The average nuts & seeds in our database has 36 mg oxalate per serving — which means Flour is 454% above the category norm. Within its specific category, Flour ranks on the higher end for oxalate. This context matters because two 'Safe' foods can have very different oxalate levels — one might have 5 mg while another has 24 mg. Both are Safe, but the first gives you more dietary flexibility. Browse all nuts & seeds rated Avoid to compare within the same verdict level.

❓ Related Questions

Why does oxalate per 100g matter?

The per-100g number lets you compare foods on an equal-weight basis, regardless of serving size. It's useful when two foods have very different typical serving sizes, or when you eat more or less than a standard serving.

How accurate is the oxalate measurement?

Harvard's 2024 analysis used ion chromatography — the gold standard for oxalate measurement. These are direct lab values, not estimates or database calculations. Variability exists between samples, but this is the most reliable reference available.

How does this compare to other foods?

Foods under 25 mg per serving are rated Safe. Foods between 25-99 mg are Caution. 100+ mg is Avoid. Check the food's category page on OxalateWatch to see how it compares to similar foods.

This is dietary reference information, NOT medical advice. Talk to your doctor or a registered dietitian before changing your diet. Oxalate tolerance varies by person, stone type, and medication.