Mineral
Calcium
Also known as: Ca, Calcium ion
Essential mineral for bone health, muscle function, nerve signaling, and blood clotting.
Primary uses
- Bone health
- Muscle function
- Nerve signaling
How it works
- Structural component of bones/teeth
- Required for muscle contraction
- Nerve impulse transmission
Dosage
- Typical range
- 500-1200mg daily
- Timing
- Divided doses
- With food
- Carbonate yes, citrate optional
- Duration
- Long-term
- Special populations
- Post-menopausal women
Forms
- Citrate
- Carbonate
Safety
Common side effects
- Constipation
- Gas
Contraindications
- Hypercalcemia
Known interactions
- Warningwith iron
Calcium significantly reduces iron absorption
- Cautionwith magnesium
High calcium can impair magnesium absorption
- Cautionwith zinc
Calcium may reduce zinc absorption
- Synergywith vitamin d
Vitamin D enhances calcium absorption
- Infowith antacids
Antacids reduce calcium absorption
- Warningwith thyroid medication
Calcium blocks thyroid medication absorption
Evidence notes
Essential mineral with strong evidence for bone health
Grade A: Multiple well-designed human trials support the main claims.
Related in Mineral
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Open the checkerMedical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.