Magnesium 250 mg
21st Century
Magnesium 250 mg
4.7
★ ★ ★ ★ ★
(63969 ratings)
Magnesium 250 mg
Score 58
A very cheap and popular magnesium supplement, but its use of poorly absorbed Magnesium Oxide and inclusion of Calcium Carbonate make it inefficient for systemic magnesium benefits.
Quantity: 110 Tablet(s) • (110 servings)
Goals: flag Heart Health flag Anti-Aging flag Cardiovascular Support flag Digestive Health flag Fitness
leaderboard Score 58
A very cheap and popular magnesium supplement, but its use of poorly absorbed Magnesium Oxide and inclusion of Calcium Carbonate make it inefficient for systemic magnesium benefits.
insights Analysis
21st Century provides a very budget-friendly magnesium supplement, which accounts for its widespread use and high review count. However, the core issue is the form: magnesium oxide is largely unabsorbed by the body, meaning that for goals like energy, stress relief, or heart health, its effectiveness is minimal. Many online reviews might praise it for its laxative effect rather than its systemic health benefits. The addition of Calcium Carbonate, another low-bioavailability form of calcium, can also interfere with magnesium absorption if both compete for the same absorption pathways. For those truly seeking to increase their magnesium levels for systemic health, this product is generally not recommended by nutritionists.
- Extremely low price per serving.
- Very high review count, indicating popularity.
- Can serve as a mild laxative.
- Uses Magnesium Oxide, which has poor systemic bioavailability.
- Includes Calcium Carbonate, which can compete with magnesium absorption.
- Not ideal for achieving broader health benefits beyond laxative effect.
- May cause digestive upset (diarrhea) due to laxative effect.
- Poor absorption for systemic benefits.
- Calcium inclusion might not be ideal for dedicated magnesium supplementation.
$4.99($0.04 per serving)
 iHerb | $ 4.99 |
Ingredients
| Ingredient | Amount per serving |
|---|---|
Calcium | 65 mg |
Magnesium | 250 mg |
Categories
Magnesium 58
Its very low price and high review count are appealing, but the exclusive use of poorly absorbed magnesium oxide significantly limits its effectiveness for systemic magnesium benefits, making it primarily a laxative.
Goals
Very limited systemic absorption due to magnesium oxide and potential interference from calcium carbonate make it largely ineffective for general health benefits.
While both minerals are for bones, their forms are poorly absorbed, and they may compete, limiting true benefit.
Poor absorption renders it ineffective for supporting cellular energy production.
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Swanson
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