How Much Oxalate Is in Sweet potato?

A standard serving of Sweet potato (1/2 cup, mashed, about 134g) contains 56 mg of oxalate. That works out to roughly 42 mg per 100 grams. These numbers are direct lab measurements from Harvard T.H. Chan School of Public Health (2024), via the OHF database. For context, the safe threshold for kidney stone patients is 25 mg per serving. Based on its 56 mg, Sweet potato falls in the Caution category.
✓ Lab-Verified Data Based on Harvard T.H. Chan SPH oxalate data (2024) and NKF/AUA dietary guidelines.
56
mg oxalate
per serving
Food: Sweet potato, baked, flesh only
Serving: 1/2 cup, mashed (134 g)
Verdict: 🟡 Caution
Per 100g: 42 mg
Data: Harvard T.H. Chan SPH (2024)
🔄 Lower-Oxalate Alternatives
🟢 Garlic
0 mg / serving
🟢 Kombu Seaweed
0 mg / serving
🟢 Wakame Seaweed
0 mg / serving
🟢 Passion Fruit or Granadilla
0 mg / serving
💡 What This Means for Your Diet

The bottom line for Sweet potato: Caution (🟡) at 56 mg oxalate per serving. It's the middle of the road — usable, but with guardrails. Half portions, occasional frequency, calcium pairing, and watching your total daily intake keeps it workable.

📊 Sweet potato vs. Other Vegetables

Putting Sweet potato in context: it lands well above the category average of 27 mg. In the database, 80% of vegetables (219 of 271) fall in the 🟢 Safe group (under 25 mg oxalate/serving). The typical vegetables here averages 27 mg oxalate per serving, so Sweet potato runs 107% above that baseline. That places it on the higher end for oxalate in its category. Why this matters: the gap between two Safe foods can be wide — one may hold 5 mg oxalate while another sits at 24 mg. The lower one leaves more room in your day. See all vegetables rated Caution for a full side-by-side.

❓ Related Questions

Why does oxalate per 100g matter?

Normalizing to 100 grams removes serving-size differences, so you can judge which food is genuinely denser in oxalate. It matters most when you eat a bigger or smaller portion than the listed serving. Sweet potato comes in at 56 mg oxalate per 1/2 cup, mashed (Caution) in the measured database.

How accurate is the oxalate measurement?

The measurements use ion chromatography, the accepted reference method for oxalate. That means real lab values for each food rather than inferred numbers. Some natural variation exists between samples, but this is the strongest published data set. Applied to Sweet potato: 56 mg oxalate per 1/2 cup, mashed — Caution per Harvard (2024).

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. For context, Sweet potato measures 56 mg per 1/2 cup, mashed, rated Caution.

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.