Is Iceberg Lettuce Safe for Kidney Stones? (Safe)
mg oxalate
per serving
Serving: 1 cup shredded (72 g)
Verdict: 🟢 Safe
Per 100g: 1.4 mg
Data: Harvard T.H. Chan SPH (2024)
What this means: Iceberg Lettuce is rated Safe (🟢). At 1 mg oxalate per serving, it's well under the 25 mg safety threshold. You can include it regularly in a kidney stone diet. Pair it with calcium-rich foods (dairy, fortified plant milks) for additional protection, and drink plenty of water throughout the day.
Among vegetables, Iceberg Lettuce sits well below the category average of 27 mg. For context, 219 out of 271 vegetables (80%) are rated 🟢 Safe (under 25 mg oxalate/serving). The average vegetables in our database has 27 mg oxalate per serving — which means Iceberg Lettuce is 97% below the category norm. Within its specific category, Iceberg Lettuce ranks among the lower-oxalate options. 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 vegetables rated Safe to compare within the same verdict level.
Why does the safe threshold matter?
The 25 mg line is the reference point clinicians use to separate everyday foods from ones that need caution. Every value on this page traces back to Harvard's 2024 lab analysis, so the threshold is applied to measured data rather than estimates. Applied to Iceberg Lettuce: 1 mg oxalate per 1 cup shredded — Safe per Harvard (2024).
Can I eat this food every day?
Daily eating is fine for Safe foods (under 25 mg/serving). For Caution or Avoid foods, spread them out and alternate with low-oxalate picks. The idea is keeping your weekly oxalate load manageable, not eliminating any single food. For Iceberg Lettuce, the measured oxalate value is 1 mg per 1 cup shredded (Safe).
Where does the oxalate data come from?
Every oxalate figure is sourced from Harvard T.H. Chan SPH (2024), distributed via the OHF database. The values come from actual lab measurements of the foods — not from database averages or estimates. For Iceberg Lettuce, the measured oxalate value is 1 mg per 1 cup shredded (Safe).
Should I also check sodium and calcium?
Yes — kidney stone risk isn't just about oxalate. High sodium increases urinary calcium (a stone promoter). Adequate dietary calcium (from food, not supplements) actually binds oxalate in your gut. Check the food's full nutrition page for the complete picture. Iceberg Lettuce comes in at 1 mg oxalate per 1 cup shredded (Safe) in the measured database.