MgO-400
21st Century
Score 68
An economical, high-dose magnesium oxide supplement with minimal calcium, best for targeted magnesium intake.
Score 68
An economical, high-dose magnesium oxide supplement with minimal calcium, best for targeted magnesium intake.
Analysis
This supplement is essentially a high-dose magnesium oxide product, with 483mg of elemental magnesium per serving. Magnesium oxide delivers a high percentage of elemental magnesium, making it a common choice for those needing a substantial amount. However, it tends to be less bioavailable compared to other forms like citrate or glycinate, meaning the body may not absorb as much of it.
It also contains a small amount of calcium carbonate (130mg), which is not enough to consider it a primary calcium supplement or a balanced calcium-magnesium product. This product is best suited for individuals whose primary goal is to boost magnesium intake economically, particularly if they tolerate magnesium oxide well.
Pros
- Offers a high dose of elemental magnesium
- Very economical price per serving
- Simple formulation focusing on magnesium
Cons
- Magnesium oxide is often less bioavailable than other magnesium forms
- Minimal calcium content, not a balanced Cal/Mag product
- May cause digestive upset or laxative effects in some individuals due to magnesium oxide
Warnings
- Magnesium oxide can have a laxative effect; start with a lower dose if sensitive.
- Consider pairing with a separate, more absorbable calcium supplement if bone health is a primary concern.
- Consult a healthcare professional if you have kidney conditions or are taking medications that interact with magnesium.
$5.88($0.13 per serving)
 Amazon | $ 5.88 | |
 iHerb | $ 7.49 | |
 Pure Formulas | $ 7.94 | |
 Walmart | $ 9.20 |
Goals
Impact
High effect
Magnesium is crucial for heart rhythm and muscle function, and a high dose of magnesium can be beneficial, though bioavailability might be a factor.
Impact
High effect
Magnesium helps regulate blood pressure and supports cardiovascular muscle function, making it useful, though the form's absorption should be considered.
Impact
High effect
Magnesium is vital for muscle function and energy production, supporting fitness activities, but its absorption might vary.
Impact
High effect
Offers significant magnesium support for various bodily functions, but lacks balance in other key minerals.
Impact
High effect
Magnesium is known for its calming properties and can contribute to mood regulation, though a more bioavailable form might be preferred.
Impact
High effect
Magnesium promotes muscle relaxation and calming effects on the nervous system, potentially aiding sleep.
Impact
High effect
Magnesium is often used to help the body manage stress and promote relaxation.
Impact
Moderate effect
Magnesium oxide is commonly used for its laxative effect to help with occasional constipation. However, it can also cause digestive discomfort for some.
Ingredients
| Ingredient | Amount per serving |
|---|---|
Calcium | 130 mg |
elemental Magnesium | 483 mg |
Magnesium 75
This product provides a substantial 483mg of elemental magnesium, making it a potent option for increasing magnesium intake, though the oxide form's bioavailability can vary.
Calcium 40
The calcium content (130mg) is quite low, making this product unsuitable as a primary source of calcium.
Alternative products
70 Value 
Calcium & Magnesium
Source Naturals
This alternative offers excellent value, providing both calcium and magnesium in well-absorbed amino acid chelated forms with Vitamin D3 at a significantly lower price per serving, making it a highly effective and economical choice.
82 Value 
Chelated Cal-Mag
Carlson
While a bit higher in price per serving, this option provides superior, highly bioavailable chelated forms of calcium and magnesium for improved absorption, representing a much better investment for long-term mineral support.
82 Value 
Calcium Magnesium Zinc With L-Glutamic Acid 1000 mg : 500 mg : 50 mg
Country Life
For a slightly higher price per serving, this comprehensive blend includes zinc and L-Glutamic Acid alongside calcium and magnesium, broadening its support for general health and immunity, offering good value.
90 Performance 
Ultra-Mag
Source Naturals
This complex offers a superior blend of multiple highly bioavailable magnesium forms (citrate, glycinate, malate, succinate, taurinate) with Vitamin B6, providing comprehensive support for muscle, nerve, and energy functions beyond just magnesium oxide.
88 Performance 
Bone Restore with Vitamin K2
Life Extension
This product enhances bone and cardiovascular support through Vitamin D3 and K2, and uses multiple highly absorbable calcium forms, offering a more advanced and synergistic mineral blend than simpler carbonate/oxide forms.
89 Performance 
Organic Plant Calcium
Garden of Life MyKind Organics
Featuring organic, plant-sourced calcium and magnesium from algae, along with Vitamin D2/D3 and K2, this alternative provides a holistic and natural approach to bone and general health.
70 Budget
Calcium & Magnesium
Source Naturals
This alternative offers both calcium and magnesium in well-absorbed chelated forms with Vitamin D3 at a significantly lower cost per serving, providing a more comprehensive basic mineral blend.
75 Budget 
600+D3
21st Century
Providing calcium carbonate with Vitamin D3 at an exceptionally low price per serving, this offers a very budget-friendly option focused on foundational bone health, though without significant magnesium.
78 Budget 
Calcium 500+D3
21st Century
This option delivers calcium from oyster shell with Vitamin D3 at an incredibly low price per serving, serving as a very basic and cost-effective calcium supplement.
70 Value
Calcium & Magnesium
Source Naturals
This alternative offers excellent value, providing both calcium and magnesium in well-absorbed amino acid chelated forms with Vitamin D3 at a significantly lower price per serving, making it a highly effective and economical choice.
82 Value
Chelated Cal-Mag
Carlson
While a bit higher in price per serving, this option provides superior, highly bioavailable chelated forms of calcium and magnesium for improved absorption, representing a much better investment for long-term mineral support.
82 Value
Calcium Magnesium Zinc With L-Glutamic Acid 1000 mg : 500 mg : 50 mg
Country Life
For a slightly higher price per serving, this comprehensive blend includes zinc and L-Glutamic Acid alongside calcium and magnesium, broadening its support for general health and immunity, offering good value.
90 Performance
Ultra-Mag
Source Naturals
This complex offers a superior blend of multiple highly bioavailable magnesium forms (citrate, glycinate, malate, succinate, taurinate) with Vitamin B6, providing comprehensive support for muscle, nerve, and energy functions beyond just magnesium oxide.
88 Performance
Bone Restore with Vitamin K2
Life Extension
This product enhances bone and cardiovascular support through Vitamin D3 and K2, and uses multiple highly absorbable calcium forms, offering a more advanced and synergistic mineral blend than simpler carbonate/oxide forms.
89 Performance
Organic Plant Calcium
Garden of Life MyKind Organics
Featuring organic, plant-sourced calcium and magnesium from algae, along with Vitamin D2/D3 and K2, this alternative provides a holistic and natural approach to bone and general health.