Calcium Magnesium Zinc + D3

Name: Calcium Magnesium Zinc + D3
Brand: 21st Century
SKU: 1lAYANy8
Rating: 4.69 (110315 reviews)

21st Century

4.7

★ ★ ★ ★ ★

(110315 ratings)

Calcium 1000 mg

Magnesium 400 mg

Score

A very affordable foundational supplement for bone, heart, and immune support.

How scoring works

Quantity:90 Tablet(s) • (30 servings)

Goals:

Bone Health

Cardiovascular Support

General Health

Energy

Fitness

Digestive Health

Heart Health

Score 93

A very affordable foundational supplement for bone, heart, and immune support.

How scoring works

$5.49($0.18 per serving)

iHerb	$ 5.49
Pure Formulas	$ 5.82
Amazon	$ 7.97

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Analysis

These tablets provide 1000mg of calcium and 400mg of magnesium, using standard carbonate and oxide forms. The addition of zinc oxide and 400 IU of Vitamin D3 makes it a very practical choice for general health maintenance.

It covers the foundational needs for bone density and enzyme function without any unnecessary frills. This is an excellent choice for someone who wants to support their skeletal and immune health while staying on a strict budget.

Pros

Very low cost per serving
Includes Vitamin D3 and Zinc
One tablet covers major mineral needs

Cons

Uses less absorbable oxide and carbonate forms
No Vitamin K2 to help direct calcium

Warnings

Calcium carbonate should be taken with food
High calcium intake may cause constipation

Nutrient quality

Highest impact

The formula provides comprehensive mineral coverage for skeletal maintenance. Reliance on carbonate and oxide forms is the primary quality drawback compared to more bioavailable alternatives.

Ingredient transparency

Highest impact

Labeling clearly identifies the chemical forms and weights for every active ingredient. This transparency allows for an accurate assessment of the supplement's foundational value.

Customer satisfaction

Highest impact

Extraordinarily high review volume and strong ratings reflect a massive degree of consumer trust. Feedback confirms the product's effectiveness for foundational mineral and structural support.

Value for money

Highest impact

The cost per serving is exceptionally low for such a comprehensive mineral blend. It represents a top-tier value for consumers seeking affordable long-term mineral support.

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Goals

Selected only

Bone Health

Impact

High effect

A-

Goal Fit

Strength of Support

Coverage

Formula Quality

Features a classic mineral combination of calcium, magnesium, and zinc to support the skeletal structure and enzymatic cofactors. The presence of vitamin D3 assists in the absorption of these essential minerals.

Reliance on carbonate and oxide forms reduces the overall bioavailability compared to chelated alternatives. Low vitamin D3 levels may not be sufficient for optimal calcium regulation.

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Cardiovascular Support

Impact

High effect

A-

Goal Fit

C+

Strength of Support

C+

Coverage

Formula Quality

Magnesium Oxide and Vitamin D3 provide foundational support for heart rhythm and blood pressure management. Magnesium is a critical mineral for vascular relaxation and maintaining electrical stability within the heart muscle.

While the dosage is appropriate, the reliance on Magnesium Oxide limits overall bioavailability for cardiovascular needs. Additionally, the high ratio of Calcium relative to Magnesium may interfere with optimal mineral absorption.

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General Health

Impact

High effect

B+

Goal Fit

Strength of Support

Coverage

C-

Formula Quality

Foundational structural and systemic health are addressed by a concentrated mineral complex. This approach provides significant levels of core micronutrients to fill major daily nutritional gaps.

Calcium carbonate, magnesium oxide, and zinc oxide serve as the primary sources for structural and immune support. While provided in large quantities, the use of inorganic forms may limit the overall efficiency of the formulation.

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Energy

Impact

High effect

B+

Goal Fit

B-

Strength of Support

D+

Coverage

B+

Formula Quality

Magnesium Oxide and Calcium Carbonate provide foundational minerals for cellular health and energy cycles. Magnesium is a required cofactor for nearly all enzymes that synthesis and use ATP.

The high dose of elemental magnesium may support metabolic pathways. However, the reliance on less bioavailable oxide forms and the high calcium-to-magnesium ratio may reduce the formula's effectiveness for acute energy needs.

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Fitness

Impact

High effect

B-

Goal Fit

Strength of Support

Coverage

B-

Formula Quality

Calcium, magnesium, and zinc appear well aligned with foundational bone and muscle support.

These minerals may contribute to basic recovery, although the use of poorly absorbed forms limits their overall performance benefit.

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Digestive Health

Impact

High effect

B-

Goal Fit

C+

Strength of Support

C-

Coverage

B-

Formula Quality

Magnesium oxide and zinc oxide appear well aligned for supporting gastrointestinal motility and the maintenance of the intestinal lining. Calcium and vitamin D3 are also included to support general mineral balance and immune regulation within the gut.

The 400 milligram dose of magnesium is functional for encouraging regularity, although the oxide form is known for poor systemic bioavailability. High calcium levels relative to magnesium may compete for absorption, which can limit the overall effectiveness of the formula for digestive wellness.

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Ingredients

Display goals

Ingredient	Amount per serving
Vitamin D3 (Cholecalciferol)	10 mcg
Calcium (Calcium Carbonate)	1000 mg
Magnesium (Magnesium Oxide)	400 mg
Zinc (Zinc Oxide)	15 mg

Report overview

Calcium (Calcium Carbonate) · 1000 mg OverallScore

C+

Active Ingredient Quality & Bioavailability

Dose, Safety & Label Transparency

A+

Value

This multi-mineral formula combines calcium with magnesium and zinc to offer broader support for skeletal and immune health. It provides a high mineral load at a very low cost per serving.

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Magnesium (Magnesium Oxide) · 400 mg OverallScore

Active Ingredient Quality & Bioavailability

B+

Dose, Safety & Label Transparency

Value

Magnesium oxide is a cost-effective but poorly absorbed form of the mineral. When taken with high amounts of calcium, its effectiveness may be further reduced, so consider a balanced formula for better results.

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