MineralNo.015

Calcium

Bone & teeth structure, muscle & nerve signaling.

Typical / RDA1,000–1,200 mg

Upper limit2,500 mg

EvidenceModerate

How to take it

Timing Split dosesFood With mealsForm Citrate / carbonate

What to know

The body absorbs only ~500 mg at once, so split larger doses. Dairy, fortified foods, and greens often supply enough. Pairs with vitamin D and K2.

Interactions & cautions

Blocks iron and some antibiotics — separate by 2 h.
Needs vitamin D to absorb effectively.

Do you actually need it?

Eat yogurt and greens? A pill may be redundant.

Questions people ask about calcium

Can You Take Too Much Calcium? Side Effects and Daily LimitsYes, taking too much calcium can lead to side effects. The tolerable upper intake level is 2,500 mg daily, and exceeding it can cause issues like kidney stones.
Calcium and Vitamin D: Why You Need Both for Bone HealthCalcium needs vitamin D for proper absorption. They are often taken together for bone health, with adults needing 1,000–1,200 mg calcium and 600–800 IU vitamin D daily.
Do you need vitamin K2 if you already take calcium for bone health?Vitamin K2 helps direct calcium to bones, preventing soft tissue buildup. While calcium builds bone, K2 ensures proper utilization, making them complementary.

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Reference values: NIH Office of Dietary Supplements, adult general population. Educational information only — not medical advice. Confirm with a healthcare professional.