Deficiency/Mobility/Heart

Calcium

Essential mineral that fills dietary calcium gaps and supports bone health, especially in older adults and low-intake diets.

score

evidence

Caution

risk

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Use with caution

This supplement may interact with medications, medical conditions or sensitive populations. Review safety before use.

Overview

Forms

Safety

Stack

Quick Take

Worth it if your diet is low in calcium or needs are higher; routine high-dose use is usually unnecessary.

Calcium is an essential mineral found in dairy, calcium-set tofu, sardines with bones, fortified plant milks, and some greens. It forms the mineral structure of bone and teeth and also helps regulate muscle contraction, nerve signaling, and clotting. Supplements most reliably correct low intake, modestly preserve bone density, and in pregnancy with low calcium intake reduce preeclampsia risk. Benefit is highest for low-intake diets, postmenopausal women, older adults, and some pregnant women.

Potential benefits

Corrects low calcium intake

Reduces preeclampsia risk

Preserves bone density

May lower fracture risk

May reduce PMS symptoms

May lower blood pressure

Protocol

Amount

300-600 mg elemental calcium

Frequency

Once daily or split into 2 doses if filling a larger gap

When

With meals if using calcium carbonate; calcium citrate can be taken with or without food. Keep single doses at or below 500-600 mg.

Onset Time

Weeks for intake correction; 6-12 months for bone outcomes

Who Should Consider

Adults who get little dairy or fortified foods

Postmenopausal women

Adults 65+ with low calcium intake

Vegans not using fortified plant milks

Pregnant women with low dietary calcium

PPI users who need calcium citrate

Food Sources

Milk (~300 mg per 240 mL cup)
Yogurt (~250-400 mg per 170-225 g serving)
Calcium-set tofu (~250-500 mg per 1/2 cup)
Sardines with bones (~325 mg per 85 g)
Fortified plant milk (~300-450 mg per 240 mL)
Cooked bok choy or kale (~100-180 mg per cup)

How It Works

Calcium supplies the raw material for bone mineralization and helps suppress excess parathyroid hormone when intake is too low, which can slow bone resorption. It also acts as a signaling ion in muscle contraction, nerve transmission, and vascular function.

Updated 5/19/2026