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 · $0.59/serving

iHerbAmazon

Best for

DentalBone & Joint

Ingredients (2)

Calcium

100%

Dose

1000 mg

Target

200–600 mg

Form

Premium

Magnesium

100%

Dose

500 mg

Target

100–400 mg

Form

Standard

Other Ingredients (6)

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

How to Take It

Best taken in the evening

The Magnesium in it is what pulls this toward the evening. Calcium is easier on the stomach taken with food.

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.

General guidance based on the ingredients, not a substitute for the label or your doctor.

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.

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