What is the calcium content in Tums (calcium carbonate)?

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Calcium Content in Tums

Tums products contain varying amounts of elemental calcium depending on the formulation: regular Tums EX (extra strength) provides 300 mg of elemental calcium per tablet, Tums Ultra provides 400 mg, and Tums 500 provides 500 mg of elemental calcium per tablet. 1

Understanding Tums Formulations

The calcium content varies by product strength:

  • Tums EX (extra strength): Contains 750 mg calcium carbonate, providing 300 mg elemental calcium per tablet 1
  • Tums Ultra: Contains 1,000 mg calcium carbonate, providing 400 mg elemental calcium per tablet 1
  • Tums 500: Contains 1,250 mg calcium carbonate, providing 500 mg elemental calcium per tablet 1

Why the Difference Between Total and Elemental Calcium

Calcium carbonate contains 40% elemental calcium by weight 1. This means that only 40% of the total calcium carbonate weight represents absorbable calcium. For example, a 750 mg calcium carbonate tablet (Tums EX) provides 300 mg of elemental calcium (750 mg × 0.40 = 300 mg). 1

Practical Dosing Considerations

  • To achieve 1,500 mg of elemental calcium daily, you would need 5 tablets of Tums EX or 3.75 tablets of Tums Ultra 1
  • Take Tums with meals to optimize absorption, as calcium carbonate requires gastric acid for proper dissolution 1, 2
  • Divide doses into 500 mg or less of elemental calcium per administration to maximize absorption and minimize gastrointestinal side effects 1, 2

Important Caveats

  • Calcium carbonate is more likely to cause constipation and bloating compared to other calcium forms 1
  • If you take acid-reducing medications (proton pump inhibitors or H2 blockers), calcium citrate is preferred over calcium carbonate because it doesn't require stomach acid for absorption 1, 2
  • Do not exceed 2,000-2,500 mg of total elemental calcium per day from all sources (diet plus supplements) to avoid kidney stones and potential cardiovascular concerns 1, 2

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Calcium Supplementation with Tums

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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