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Magnesium 500 mg

Sundown

4.7
(30035 ratings)
Magnesium 500 mg
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Score 60.0

A very affordable high-dose magnesium supplement, but its reliance on poorly absorbed Magnesium Oxide limits its efficacy for systemic health benefits, making it more suitable for digestive regularity.

Quantity: 180 Tablet(s)Servings size: 1 Caplet(s) (180 servings)
Selected goals:
Other goals:
Stress Relief
Mood Support
Bone Health
Sleep Support
General Health

Score 60.0

A very affordable high-dose magnesium supplement, but its reliance on poorly absorbed Magnesium Oxide limits its efficacy for systemic health benefits, making it more suitable for digestive regularity.

Analysis

Sundown's Magnesium 500 mg is attractive due to its low price and high dosage. However, the exclusive use of magnesium oxide significantly impacts its overall utility. Magnesium oxide contains a high percentage of elemental magnesium by weight, but its absorption rate in the body is notoriously low (estimated around 4%). This means that while you're taking 500mg, only a small fraction is likely to be utilized for systemic functions like energy production, muscle relaxation, or nerve function. It excels as an osmotic laxative, which is reflected in many online reviews. For comprehensive magnesium supplementation, more bioavailable forms are typically recommended.

Pros
  • Extremely low price per serving.
  • High elemental magnesium content per dose.
  • Very popular, indicated by high review count.
  • Effective for constipation relief.
Cons
  • Magnesium Oxide has poor systemic bioavailability.
  • Not ideal for achieving broader health benefits beyond laxative effect.
Warnings
  • May cause digestive upset (diarrhea) in higher doses due to laxative effect.
  • Not the best choice if your primary goal is systemic magnesium absorption for energy, mood, etc.
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$7.87($0.04 per serving)
Amazon
$ 0.00
iHerb
$ 7.87
Vitacost
$ 8.69
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Effectiveness for goals

Dosage, timing & forms

Safety & interactions

Ingredients

IngredientAmount per serving
Magnesium (Magnesium Oxide) 500 mg
Gluten Free Adults 18–50 Dairy Free Sugar Free Vegetarian
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Categories

Though incredibly cheap and high-dose, the exclusive use of magnesium oxide significantly limits its systemic absorption, making it primarily useful for laxative effects rather than comprehensive magnesium support.

Goals

Limited systemic absorption of magnesium oxide means it contributes minimally to overall general health beyond digestive regularity.
Due to poor absorption, the magnesium oxide is unlikely to significantly support cellular ATP production needed for energy.
Systemic absorption is crucial for magnesium's role in stress management; magnesium oxide is poorly suited for this.
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Offers an even lower price per serving (0.03) for magnesium oxide, making it the most budget-friendly alternative for this form.
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Provides a very low price per serving (0.04) for magnesium oxide, offering a similarly cheap option for basic magnesium.
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Magnesium 200 mg

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(927 ratings)
A highly affordable magnesium oxide option with a low price per serving (0.04), providing a direct cost-effective alternative.
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Magnesium Caps 500 mg

Life Extension
4.8
(71620 ratings)
Exceptional value, combining a premium, highly bioavailable multi-magnesium blend with an excellent price per serving (0.08), offering a superior product for a reasonable cost increase.
95 Value

Triple Magnesium Complex 400 mg

Swanson Premium Brand
4.8
(15546 ratings)
Provides a balanced blend of magnesium forms (Oxide, Citrate, Aspartate) at a very competitive price per serving (0.11), offering better overall efficacy than pure oxide for a slightly higher cost.
90 Value

Target-Mins Magnesium Potassium Aspartate With Other Target-Mins Chelates

Country Life
4.7
(4315 ratings)
Offers a diverse blend of magnesium forms and potassium, providing comprehensive mineral support with better absorption than oxide, at a reasonable price (0.23/serving).
100 Performance

Magnesium Caps 500 mg

Life Extension
4.8
(71620 ratings)
Features a premium blend including highly bioavailable TRAACS Lysyl Glycinate Chelate, offering vastly superior absorption and efficacy for systemic benefits over magnesium oxide.
98 Performance

Chelated Magnesium 133 mg

Swanson
4.8
(5354 ratings)
Contains TRAACS Magnesium Bisglycinate Chelate, a highly absorbed and gentle form of magnesium, ideal for addressing deficiencies effectively, unlike oxide.
95 Performance

Magnesium & Calcium

NOW
4.8
(16706 ratings)
Offers a comprehensive blend of well-absorbed magnesium forms including Glycinate and Citrate, providing significantly better bioavailability than magnesium oxide.
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