You're getting 1,000mg of **Calcium** as calcium citrate — a well-absorbed form that doesn't require stomach acid to work. That's a full day's RDA in one serving, which is generous, but your body can only absorb about 500mg of calcium at a time. To get the most out of this, you'd want to split the 5-tablet serving across two meals rather than taking them all at once.

**Magnesium** is dosed at 500mg, which covers the full clinical supplemental range (100–400mg). However, the form is a mix of magnesium citrate and magnesium oxide — citrate absorbs well, but oxide has roughly 4% absorption, so you're not getting the full 500mg worth of usable magnesium. Worth noting: 500mg exceeds the tolerable upper limit of 350mg for supplemental magnesium, which may cause digestive discomfort for some people.

The biggest gap here is the absence of **Vitamin D** and **Vitamin K2**. Without vitamin D, your body absorbs only 10–15% of the calcium in this product. If you're taking this for bone support, pairing it with a separate D3+K2 supplement is essential to get real benefit from the calcium dose.

BioStacks
Solgar

Calcium Magnesium Citrate

5 Tablets · 20 servings

iHerbAmazon
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What it does

A combination of 2 label ingredients.

Magnesium

Mixed formsGrade —

Supports normal muscle and nerve function and helps the body produce energy.

Calcium

calcium citratePremium

Supports the maintenance of normal bones and teeth, muscle function and nerve signaling.

DentalBone & Joint
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Ingredients (2)

Other ingredients

Silicon DioxideAnti-caking

Fine silica powder used to prevent clumping

Magnesium StearateLubricant

A salt of stearic acid used as a lubricant in tablet and capsule production

Microcrystalline CelluloseBinder

Plant-derived cellulose used as a binder and filler in supplements

Stearic AcidLubricant

Saturated fatty acid used as tablet lubricant

Microcrystalline CelluloseBinder

Plant-derived cellulose used as a binder and filler in supplements

GlycerinHumectant

Sweet-tasting liquid used in soft capsules and liquids

Lab testing

How to take it

With food
Keep it away from high-oxalate foods like spinach
Space it a couple of hours from Iron and Zinc

On the label

Suggested Use: As a dietary supplement for adults, take five (5) tablets daily, preferably with a meal. May be distributed throughout the day, or as directed by a healthcare practitioner.

Price check

$11.84

$10$20$50

Cheaper than 77% of 294 calcium supplements

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Sources & Scoring

Nutrient data (RDA, UL, and safety thresholds) sourced from the NIH Office of Dietary Supplements and the National Academies Dietary Reference Intakes (DRI).

This is not medical advice. Consult a healthcare provider before making changes to your supplement routine.

The score analyzes what's on the label: ingredient doses vs. studied ranges, chemical forms, evidence levels, and known interactions. It does not verify label accuracy or test for contaminants — for that, look for third-party certifications like USP or NSF.

Not medical advice. Consult your healthcare professional.

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