🟢 Safe
Oxalate <25 mg/serving
🟡 Caution
Oxalate 25-99 mg/serving
🔴 Avoid
Oxalate ≥100 mg/serving
🟢

Nuts, Walnuts, raw or roasted

🟢 Low Oxalate — Low Oxalate
18 mg oxalate / serving
Serving: 1/4 cup (29 g) | Per 100 g: 62 mg
✓ Lab-Verified Data Oxalate values from Harvard T.H. Chan SPH Oxalate Database (2024), measured via ion chromatography. This site is a dietary reference tool, not a medical resource.

Walnuts are moderate in oxalate at 18 mg per ounce — safely in the green zone. They're rich in omega-3 fatty acids (the plant form, ALA) and have a distinctly earthy flavor. A handful as a snack or chopped onto a salad is fine. Walnut butter is a good alternative to almond butter. The omega-3 content makes walnuts arguably the healthiest nut overall — and from an oxalate perspective, they're well within the safe range. Just don't eat an entire bag in one sitting.

📊 Nutrition at a Glance

18 mg
Oxalate / serving
Low Oxalate
0 mg
Sodium / 100g
Low Na
14.6 g
Protein / 100g
Tier 1
88 mg
Calcium / 100g
Tier 1

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 Walnuts Nuts at 18 mg per serving, in the middle of the family range. Related forms in this family: Pecans raw or roasted Nuts (15 mg), Soynuts Nuts (24 mg), Macadamia Nuts (13 mg).

📏 Oxalate by Serving Size

ServingWeightOxalateVerdict
1/4 cup29 g18 mg Low Oxalate
2 x 1/4 cup58 g36 mg Moderate Oxalate
½ x 1/4 cup14 g9 mg Low Oxalate

🏷️ Tags

Nuts & Seeds 🟢 Oxalate Safe Low Oxalate

🟢 See all Nuts & Seeds rated Safe for kidney stones →

🔗 Related Foods

❓ Frequently Asked Questions

Can I eat Nuts with kidney stones?

Yep, you're good. Nuts clocks in at 18 mg oxalate per 1/4 cup — way under the 25 mg cutoff. Eat it without the stress. Measured by Harvard, not guessed.

What's the oxalate content of Nuts?

Quick math: 1/4 cup of Nuts = 18 mg oxalate. 100g = 62 mg. Both numbers come from Harvard's latest lab measurements. Not AI, not a database, actual lab work.

Is Nuts low or high oxalate?

Nope. Nuts is a low-oxalate food — just 18 mg per 1/4 cup. Well under the 25 mg cutoff. You're in the clear with this one.

What are the best low-oxalate alternatives to Nuts?

Substitutes exist. The safe alternatives listed below are all low-oxalate foods in the same family as Nuts. Grab one of those and you dodge the oxalate while keeping similar flavors.

How much sodium does Nuts have?

Low sodium: 0 mg/100g. That's a non-issue for kidney stones. Just don't undo it by drowning it in salt during cooking.

📚 Data Sources

Oxalate: Harvard T.H. Chan School of Public Health (2024) via OHF. Nutrition: USDA FoodData Central (SR Legacy 2018 & Foundation Foods).

📖 Key Scientific References

Taylor EN, Curhan GC. Oxalate intake and the risk for nephrolithiasis. J Am Soc Nephrol. 2007;18(7):2198-2204. PMID: 17538185
Borghi L, Schianchi T, Meschi T, et al. Comparison of two diets for the prevention of recurrent stones in idiopathic hypercalciuria. N Engl J Med. 2002;346(2):77-84. DOI: 10.1056/NEJMoa010369
Fink HA, Akornor JW, Garimella PS, et al. Diet, fluid, or supplements for secondary prevention of nephrolithiasis. Eur Urol. 2009;56(1):72-80. DOI: 10.1016/j.eururo.2009.03.031
Ferraro PM, Taylor EN, Gambaro G, Curhan GC. Dietary and lifestyle factors for primary prevention of nephrolithiasis. BMC Nephrol. 2020;21(1):267. PMID: 32652950
Pearle MS, Goldfarb DS, Assimos DG, et al. Medical management of kidney stones: AUA guideline. J Urol. 2014;192(2):316-324. DOI: 10.1016/j.juro.2014.05.006
Liebman M, Costa G. Effects of calcium and magnesium on urinary oxalate excretion after oxalate loads. J Urol. 2000;163(5):1565-1569. PMID: 10751889
Holmes RP, Assimos DG. The impact of dietary oxalate on kidney stone formation. Urol Res. 2004;32(5):311-316. DOI: 10.1007/s00240-004-0437-3
Lin BB, Lin ME, Huang RH, et al. Dietary treatment and fluid intake for prevention of recurrent calcium stones. PLoS One. 2021;16(4):e0250257. PMID: 33872340
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.