Calcium Citrate
Calcium bound to citric acid. It absorbs well with or without food and does not depend on stomach acid, which makes it the better pick for older adults and anyone on acid-reducing medication. It carries less elemental calcium per pill, so you may need slightly more.
Best for
Any time, sensitive stomachs, low stomach acid
Absorption
High
Tolerability
Gentle; no food required
Typical timing
Citrate any time; carbonate with food. Split doses above 500 mg.
How to take Calcium Citrate
A typical dose of Calcium: 500–1,000 mg per day from supplements, only to fill dietary gaps. Best timing: Citrate any time; carbonate with food. Split doses above 500 mg.. The form you choose mainly affects absorption and how easily it sits with your stomach, not the overall dose.
Where to buy Calcium Citrate
Choose a third-party-tested brand; the label should name this form explicitly.
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