Is Roasted red peppers Safe for Kidney Stones? (Safe)
mg oxalate
per serving
Serving: 1/2 cup (75 g)
Verdict: 🟢 Safe
Per 100g: 1.3 mg
Data: Harvard T.H. Chan SPH (2024)
The bottom line for Roasted red peppers: Safe (🟢), with 1 mg oxalate per serving — comfortably below the 25 mg safe cutoff. There's no need to limit it. Just keep your usual kidney stone basics in place: water throughout the day and calcium-rich foods at meals.
Putting Roasted red peppers in context: it lands well below 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 Roasted red peppers runs 97% below that baseline. That places it among the lower-oxalate options 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 Safe for a full side-by-side.
Why does the safe threshold matter?
The 25 mg cutoff comes from clinical guidance for stone formers. Below it, a food's oxalate contribution is small enough not to move the needle for most patients. Harvard's 2024 lab data sits behind these figures — direct measurements, not estimates. Applied to Roasted red peppers: 1 mg oxalate per 1/2 cup — 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 Roasted red peppers, the measured oxalate value is 1 mg per 1/2 cup (Safe).
Where does the oxalate data come from?
The numbers come from Harvard T.H. Chan SPH's 2024 laboratory measurements, published through the OHF database. Direct lab analysis, which is why they're treated as the reference values for food oxalate. For Roasted red peppers, the measured oxalate value is 1 mg per 1/2 cup (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. Roasted red peppers comes in at 1 mg oxalate per 1/2 cup (Safe) in the measured database.