Is Crab Safe for Kidney Stones? (Safe)
mg oxalate
per serving
Serving: 3 oz (85 g)
Verdict: 🟢 Safe
Per 100g: 0 mg
Data: Harvard T.H. Chan SPH (2024)
In practical terms, Crab is a low-risk food for kidney stone patients. Its 0 mg oxalate per serving stays under the 25 mg line, so it can appear in your regular rotation without extra calculation. As always, staying hydrated and getting dietary calcium supports stone prevention.
Among seafood, Crab sits well below the category average of 2 mg. For context, 55 out of 55 seafood (100%) are rated 🟢 Safe (under 25 mg oxalate/serving). The average seafood in our database has 2 mg oxalate per serving — which means Crab is 100% below the category norm. Within its specific category, Crab 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 seafood rated Safe to compare within the same verdict level.
Why does the safe threshold matter?
The 25 mg per serving threshold is based on clinical guidance for kidney stone patients. Harvard's lab data (2024) provides the most reliable oxalate measurements available — no database estimates, direct lab analysis. Crab comes in at 0 mg oxalate per 3 oz (Safe) in the measured database.
Can I eat this food every day?
If it's in the Safe zone (under 25 mg/serving), yes — it can be a regular part of your diet. For Caution or Avoid foods, frequency matters. Rotate them with lower-oxalate options throughout the week. For context, Crab measures 0 mg per 3 oz, rated Safe.
Where does the oxalate data come from?
Harvard T.H. Chan School of Public Health (2024) via the OHF database. These are direct laboratory measurements — the most reliable oxalate data available for food. For Crab, the measured oxalate value is 0 mg per 3 oz (Safe).
Should I also check sodium and calcium?
Yes — oxalate alone doesn't decide stone risk. Sodium pushes more calcium into urine, and calcium from food (not supplements) helps bind oxalate during digestion. The main food page covers sodium and calcium alongside oxalate. Crab comes in at 0 mg oxalate per 3 oz (Safe) in the measured database.