Mineral
Calcium Carbonate
Also known as: Caltrate, Tums
Common, economical calcium form with highest elemental calcium percentage. Requires stomach acid for absorption.
Daily target & upper limit
1300 mg / day · UL 2500 mgCalcium Carbonate has an established daily reference intake. See best forms, label synonyms, upper-limit warnings, and top-scoring supplements:
Calcium Carbonate dosage reference →Primary uses
- Bone health
- Calcium supplementation
How it works
- Highest elemental calcium %
- Requires stomach acid
- Also an antacid
Dosage
- Typical range
- 500-1000 mg daily
- Timing
- With meals
- With food
- Yes, needs acid
- Duration
- Safe long-term
- Special populations
- Take with food for absorption
Forms
- Tablet
- Chewable
Safety
Common side effects
- Constipation
- Gas
Contraindications
- Same as citrate
Known interactions
- Warningwith calcium
Calcium significantly reduces iron absorption
- Cautionwith calcium
High calcium can impair magnesium absorption
- Cautionwith calcium
Calcium may reduce zinc absorption
- Synergywith vitamin d
Vitamin D enhances calcium absorption
- Infowith calcium
Antacids reduce calcium absorption
- Warningwith calcium
Calcium blocks thyroid medication absorption
Evidence notes
Economical calcium source
Grade A: Multiple well-designed human trials support the main claims.
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Open the checkerMedical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.