Calcium
mineralAlso known as: Calcium Carbonate, Calcium Citrate, Calcium Hydroxyapatite
About
Calcium is essential for cardiac muscle contraction-relaxation cycling and maintaining normal heart rhythm. However, a 2010 BMJ meta-analysis of 11 RCTs found calcium supplements (without vitamin D) were associated with a 31% increased risk of myocardial infarction. Current AHA guidance suggests obtaining calcium preferentially from food sources rather than supplements.
How It Works
Essential for cardiac muscle contraction-relaxation cycling through calcium-induced calcium release from the sarcoplasmic reticulum; maintains normal heart rhythm; low dietary calcium associated with increased PTH and RAAS activation which may promote hypertension; calcium from food sources may have different cardiovascular effects than supplemental calcium.
Evidence For Conditions
| Condition | Grade | Studies | Participants | |
|---|---|---|---|---|
| High Blood Pressure (Hypertension) | C | 13 | 1500 | View → |
Side Effects
- Constipation (especially carbonate form)
- Potential increased MI risk with high-dose supplements (controversial)
- Kidney stones at excessive doses
- Gas, bloating
Drug & Supplement Interactions
- Thyroid medications (separate by 4 hours)
- Bisphosphonates (separate by 30-60 minutes)
- Iron supplements (reduced absorption — separate by 2 hours)
- Certain antibiotics (reduced absorption)
- Vitamin K2 (may help direct supplemental calcium to bones, not arteries)
Always inform your healthcare provider about all supplements you take.
Related Ingredients
FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. The products and information on this website are not intended to diagnose, treat, cure, or prevent any disease. The evidence grades presented are based on our analysis of published peer-reviewed research and do not constitute medical advice. Always consult your healthcare provider before starting any supplement regimen.