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Coral Calcium 1000 mg
21st Century
4.7
★ ★ ★ ★ ★
(1073 ratings)
Calcium 1000 mg
Magnesium 500 mg
Score 68.0
A high-dose calcium and magnesium supplement with D3, but its effectiveness is hindered by the use of less bioavailable coral calcium and magnesium oxide forms, making it less cost-efficient for actual mineral absorption.
Quantity: 120 Capsule(s)Servings size: 4 Capsule(s) (30 servings)
Selected goals:
Other goals:
Bone Health
Joint Health
Heart Health
Fitness
Stress Relief
leaderboard Score 68.0
A high-dose calcium and magnesium supplement with D3, but its effectiveness is hindered by the use of less bioavailable coral calcium and magnesium oxide forms, making it less cost-efficient for actual mineral absorption.
21st Century's Coral Calcium 1000 mg aims to provide a substantial dose of calcium and magnesium for bone and general health, supplemented with Vitamin D3. The inclusion of Vitamin D3 is a significant advantage, as it is the most effective form for promoting calcium absorption and utilization in the body. The 1:1 calcium to magnesium ratio is well-balanced and often recommended for comprehensive mineral support. However, the primary sources for both minerals, coral calcium and magnesium oxide, are concerns. Coral calcium, while naturally sourced, generally has an absorption profile similar to calcium carbonate, which requires stomach acid for optimal uptake. Magnesium oxide, despite its high elemental magnesium content, is widely recognized for its poor bioavailability, meaning a large portion passes through the digestive system unabsorbed. This limits the true effectiveness of the high dosages claimed and makes the $0.47 per serving price less competitive when considering actual mineral delivery.
- Contains Vitamin D3 (Cholecalciferol), the most bioavailable form of Vitamin D, essential for calcium absorption.
- Provides a 1:1 ratio of calcium to magnesium, which is a balanced and often recommended ratio.
- Offers high elemental doses of both calcium (1000mg) and magnesium (1000mg).
- Relies heavily on coral calcium and magnesium oxide, which are less bioavailable forms of these minerals, potentially limiting actual absorption.
- The price of $0.47 per serving is relatively high considering the lower bioavailability of the primary mineral forms.
- The listed magnesium from 'Coral Calcium' is ambiguous and potentially double-counted with the 'Magnesium Oxide' if the 500mg from coral calcium is not elemental magnesium.
- Individuals with low stomach acid may struggle to absorb the coral calcium effectively.
- A significant portion of the magnesium oxide may not be absorbed, limiting its systemic benefits and potentially causing digestive upset in some individuals.
$15.99($0.53 per serving)
 Amazon | $ 15.99 | |
 iHerb | $ 15.99 |
| Ingredient | Amount per serving |
|---|---|
| Vitamin D3 (Cholecalciferol) | 10 mcg |
| Calcium | 1000 mg |
| Magnesium (Magnesium Oxide, Coral Calcium) | 500 mg |
Categories
Calcium 60.0
Provides a high dose of calcium, but the coral calcium form is not optimally absorbed compared to citrate or malate.
Magnesium 50.0
Offers a high elemental dose, but the primary form is magnesium oxide, which is known for its poor bioavailability.
Goals
Bone Health 65.0
Includes a good dose of Calcium and Vitamin D3, which is beneficial for bone health. However, the use of coral calcium (similar to carbonate) for calcium and poorly absorbed magnesium oxide means that the actual bioavailability for bone building is not optimal.
Joint Health 60.0
Provides general mineral support for the skeletal system, which indirectly benefits joints, but the lower bioavailability of the mineral forms and lack of specific joint-supporting compounds limit its direct impact.
Heart Health 60.0
Calcium and magnesium are crucial for cardiovascular function, but the poor absorption of magnesium oxide reduces its effectiveness for supporting heart health compared to products with more bioavailable forms.
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