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Calcium 500+D3

21st Century

4.8
★ ★ ★ ★ ★
(5027 ratings)
Calcium 500 mg
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Score 75

An affordable calcium carbonate (oyster shell) supplement with Vitamin D3, offering great value for basic bone health.

Quantity: 90 Tablet(s) • (90 servings)
Goals:
flag Bone Health
flag Nail Health

leaderboard Score 75

An affordable calcium carbonate (oyster shell) supplement with Vitamin D3, offering great value for basic bone health.

Quantity: 400Quantity: 400Quantity: 90

insightsAnalysis

21st Century's Calcium 500+D3 is a highly popular and affordable supplement that combines calcium, primarily from oyster shell (a form of calcium carbonate), with essential Vitamin D3. The inclusion of D3 is paramount as it significantly enhances calcium absorption in the gut and its proper utilization for bone mineralization, directly addressing a common deficiency in many calcium-only supplements. While oyster shell calcium is a carbonate form and may require stomach acid for absorption, its very low price per serving and high volume of positive reviews make it an excellent entry-level option for general bone, joint, and heart health support, offering significant value to consumers.
thumb_upPros
  • Includes Vitamin D3, which is crucial for calcium absorption and bone health.
  • Extremely low price per serving, offering exceptional affordability.
  • Very high number of positive reviews, indicating widespread consumer satisfaction.
thumb_downCons
  • Oyster shell calcium is primarily calcium carbonate, which can be less bioavailable for some and potentially associated with heavy metals (though usually purified by reputable brands).
  • Ingredient list provided does not explicitly list D3, despite the product name.
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$4.94($0.05 per serving)
iHerb
$ 4.94
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Ingredients

IngredientAmount per serving
Vitamin D3
5 mcg
Calcium
500 mg
grain_off Gluten Free person Adults 18–50
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Categories

Calcium 75
This product sets a high bar for value in the calcium category by offering both calcium and Vitamin D3 at an incredibly low price, directly addressing the primary needs for effective calcium supplementation.

Goals

flag Bone Health 80
The inclusion of Vitamin D3 is a significant advantage, directly supporting calcium absorption and bone mineralization, making it effective for bone health despite the calcium carbonate form. Its affordability ensures consistent intake, further benefiting long-term bone density.
flag Joint Health 75
By improving calcium absorption through the presence of Vitamin D3, this supplement supports stronger bones, which in turn provide better structural support for joints. This makes it a more effective choice for joint health than calcium-only products.
flag Heart Health 70
Calcium is vital for cardiovascular function, and with improved absorption from D3, it supports healthy heart muscle and nerve signaling. Its cost-effectiveness can encourage consistent use, benefiting overall heart health.
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