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Calcium 500+D3

21st Century
4.8
★ ★ ★ ★ ★
(5261 ratings)
Product Image
Score 78

This highly affordable supplement provides 500mg of oyster shell calcium with added Vitamin D3, offering effective and economical support for bone and nail health.

How scoring works
scaleQuantity:400 Tablet(s) • (400 servings)
track_changesGoals:

leaderboard Score 78

This highly affordable supplement provides 500mg of oyster shell calcium with added Vitamin D3, offering effective and economical support for bone and nail health.

How scoring works
Also available as 3 options
400 servings 1 Tablet(s) • 400 Tablet(s) • 400 servings $10.99 ($0.02 per serving) 90 servings 1 Tablet(s) • 90 Tablet(s) • 90 servings $5.49 ($0.06 per serving) 90 servings 1 Tablet(s) • 90 Tablet(s) • 90 servings $5.49 ($0.06 per serving)
$6.72($0.01 per serving)
Pure Formulas
$ 6.72
iHerb
$ 10.99
Walmart
$ 14.58
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psychologyAnalysis

The 21st Century Calcium 500+D3 offers 500mg of elemental calcium derived from oyster shell, combined with 5mcg (200 IU) of Vitamin D3. Oyster shell calcium is primarily calcium carbonate, often containing natural trace minerals, and the added D3 supports calcium absorption.

This product is a practical choice for individuals seeking to bolster their daily calcium intake for bone and nail health, particularly appealing due to its remarkably low price per serving and generous quantity, making it an excellent long-term supplement option.

thumb_upPros
  • Extremely low price per serving, offering outstanding affordability.
  • Includes Vitamin D3 to aid calcium absorption.
  • Good elemental calcium dose per serving (500mg).
  • High quantity (400 servings) ensures a long-lasting supply.
thumb_downCons
  • Calcium from oyster shell is primarily calcium carbonate, which may cause digestive issues for some.
  • The Vitamin D3 dose (200 IU) is on the lower side compared to some other combination products.
  • May require taking with food for optimal absorption.
warningWarnings
  • As oyster shell calcium is largely calcium carbonate, those with sensitive stomachs should consider taking it with food.
  • If you require higher doses of Vitamin D, you might need an additional Vitamin D supplement to meet your needs.
scienceNutrient quality
75 High impact

The combination of oyster shell calcium and Vitamin D3 provides a practical and generally effective nutrient profile for calcium needs, despite the moderate D3 dose.

visibilityIngredient transparency
80 Highest impact

The product clearly specifies the calcium source (Oyster) and quantity, along with the Vitamin D3 amount, ensuring clear information for consumers.

workspace_premiumValue for money
95 Highest impact

The exceptionally low price per serving, combined with a good calcium dose and D3, offers outstanding value for long-term use and consistent supplementation.

thumb_upCustomer satisfaction
90 Highest impact

With over 5000 reviews, this product demonstrates very high customer satisfaction and popularity, suggesting a well-received and trusted option.

storefrontBrand
65 High impact

21st Century is known for offering very affordable and basic, yet effective, nutritional supplements, appealing to value-conscious consumers.

flagReport analysis
track_changesGoals
flagBone Health
Impact
Highest effect
Provides a good elemental calcium dose supported by Vitamin D3, which is a crucial combination for maintaining and building strong bones, especially given its affordability.
View goal →
flagNail Health
Impact
Highest effect
The adequate calcium content, combined with Vitamin D3 for absorption, makes it a reliable choice for supporting strong and healthy nails.
View goal →
scienceIngredients
IngredientAmount per serving
Vitamin D3
5 mcg
Calcium
500 mg
grain_off Gluten Free person Adults 18–50
flagReport overview
Calcium 82
Delivers a solid dose of calcium, enhanced by Vitamin D3, making it a well-rounded and effective calcium supplement for general daily intake.
scienceView ingredientinventory_2View products
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