Why are canned sardines so high in calcium?

100 g of Sardine, Atlantic, canned in oil, drained solids with bone contains 382 mg of calcium, which is 29% of the Daily Value.

What this means for you

Because you eat the bones. Canning softens them until they disappear into the fish, and bone is where a fish keeps its calcium. That is the whole explanation.

A drained cup of sardines canned in oil carries roughly 570 mg of calcium, which is over half an adult's daily requirement from one tin. It also happens to be absorbable calcium rather than the kind that is bound up, as it is in spinach, where only about 5 per cent gets through.

The same tin brings vitamin D, which almost no other food does naturally, and a large amount of vitamin B12. For anyone who does not drink milk, tinned fish with the bones in is the most underrated item in this entire database.

Two caveats, both small. Tinned fish carries salt, so if you are watching sodium the drained weight and the label are worth a glance. And sardines packed without bones lose the whole point of this page, so check which tin you are buying.

Written from the evidence cards and the data on this page, then checked back against the sources. Bioma Learn has no human medical reviewer at this time and we say so rather than invent one. Information, not medical advice. How we verify.

Full nutrition for this food, including all 30 vitamins and minerals we hold: Sardine, Atlantic, canned in oil, drained solids with bone →

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Data: USDA FoodData Central, FDC ID 175139. % Daily Value against FDA. Checked 2026-09-15.