Research
Micronutrients & recovery
The bioavailability of calcium varies significantly by food source; while milk products offer ~30% bioavailability, spinach is poor (~5%) due to oxalic acid, whereas soya beans are bioavailable (30-40%) despite containing oxalic and phytic acids.
Don't just count milligrams; consider where they come from. Milk and fortified cereals are good sources. Spinach has calcium but it's poorly absorbed. If you eat soy, you are getting a bioavailable form of calcium, similar to milk.
GoodQualifiesHIGH confidence
The bioavailability of calcium from milk and milk products is in the region of 30% compared to 5% from spinach... Soya beans are also a notable exception, in that they contain high quantities of both oxalic and phytic acids, yet are a bioavailable source of calcium (bioavailability is in the region of 30-40%).
Why this rating
The paper cites specific bioavailability percentages for different foods based on existing literature.
Source
Dietary calcium and health
Hannah Theobald · Nutrition Bulletin · 2005
narrative_reviewCited 201×
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