Calcium Carbonate
Overview
Calcium carbonate (CCaO3) is a common calcium supplement and antacid. Calcium is essential for bone mineralization, muscle contraction, nerve function, and coagulation. RDA: 1000–1200 mg/day (elemental calcium). Calcium carbonate is 40% elemental calcium — most concentrated but requires stomach acid for absorption (take with food). UL: 2000–2500 mg/day. Risk of hypercalcemia, kidney stones, and cardiovascular concerns at high doses. Caution in CKD (impaired excretion). Interaction: reduces absorption of iron, zinc, thyroid hormones, and tetracyclines.
Dosage
500 mg · Any time · Can take on empty stomach
Key Interactions
12 verified interactions found
Calcium carbonate with vitamin D increases calcium excretion in the body.
Vitamin D3 steigert die Calcium-Aufnahme erheblich; die Kombination mit Calciumcarbonat erhöht die Gesamt-Calciumzufuhr stark. Gesamt-Calciumzufuhr aus Supplementen auf ≤500mg/Tag begrenzen und Gesamtzufuhr inkl. Nahrung prüfen (BfR 2024).
View details →See Iron entry. Calcium carbonate has stronger iron-inhibition effect than citrate form due to pH elevation.
Separate from iron by 2+ hours. Iron on empty stomach with vitamin C.
View details →Calcium Carbonat ≥300–500 mg hemmt intestinale Eisenabsorption akut um ~30–50%. Zusätzlich erhöht Calcium Carbonat den intestinalen pH (benötigt Magensäure zur Auflösung) und hemmt so die Fe³⁺→Fe²⁺-Reduktion, die für die DMT1-abhängige Eisenaufnahme nötig ist.
Calcium Carbonat und Eisensupplemente nie gleichzeitig einnehmen (mind. 2 Stunden Abstand). Bei Eisenmangelrisiko Calcium Citrat bevorzugen — weniger pH-Effekt auf Eisenabsorption.
View details →Magnesium citrate has dose-dependent absorption; splitting high doses does not enhance tissue accumulation
Take magnesium citrate with food to maximize absorption; separate from high-dose calcium by 2+ hours
View details →Boron reduces urinary calcium excretion and supports calcium integration into bone matrix. Together they support bone mineral density maintenance.
Combine for bone health.
View details →Scientific Sources
- Bioavailability of calcium supplements and the effect of Vitamin D: comparisons (1996)
- Bioavailability of Calcium: Comparison of Calcium Carbonate and Milk and the Eff (2005)
- Chronically Hypocalcemic Patient with Hypercalcemia. (2016)
- [Management of phosphate in chronic kidney disease--Chemistry and history of pho (2009)
- Clinical response in patients with dengue fever to oral calcium plus vitamin D a (2009)
- pubmed
- Boron + Ca (PMID:17473380)
- Boron + Ca (PMID:22782709)
- Boron + Ca (PMID:22439438)
- NIH Dietary Supplement Label Database (DSLD)
- PubChem Compound 10112
Frequently Asked Questions
What is Calcium Carbonate used for?
Calcium carbonate (CCaO3) is a common calcium supplement and antacid.
What is the recommended dosage for Calcium Carbonate?
500 mg. Any time. Can take on empty stomach.
Does Calcium Carbonate interact with other supplements?
Calcium Carbonate has 12 verified interactions. Top: Vitamin D3 (Cholecalciferol), Eisen.
When is the best time to take Calcium Carbonate?
Any time. Can take on empty stomach.
Is Calcium Carbonate safe to combine with other supplements?
Always check interactions before combining supplements. Use VitalStack to verify your full stack for free.
Check how Calcium Carbonate fits your full stack
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Check Your Stack →Not medical advice. VitalStack is not a medical device. For personalized health recommendations, consult a healthcare provider.