Calcium 500 + D3
21st Century
Calcium 500 + D3
4.8
★ ★ ★ ★ ★
(4031 ratings)
Calcium 500 mg
Score 75.0
An exceptionally affordable calcium carbonate supplement from oyster shell, combined with Vitamin D3 for enhanced absorption and effective bone support.
Quantity: 400 Tablet(s)Servings size: 1 Tablet(s) (400 servings)
Selected goals:
Other goals:
Bone Health
Heart Health
Joint Health
Muscle Gain
Fitness
leaderboard Score 75.0
An exceptionally affordable calcium carbonate supplement from oyster shell, combined with Vitamin D3 for enhanced absorption and effective bone support.
insights Analysis
21st Century's Calcium 500 + D3, sourced from Oyster Shell, presents a highly economical solution for calcium supplementation. It delivers 500mg of elemental calcium per serving, paired with 15mcg (600 IU) of Vitamin D3. The inclusion of Vitamin D3 is a significant advantage, as it plays a pivotal role in optimizing the body's absorption of calcium and its proper integration into bone tissue, enhancing the overall efficacy for bone health. While oyster shell calcium is essentially calcium carbonate and therefore best absorbed when taken with food, its outstanding affordability makes it an accessible and effective option for individuals looking to maintain adequate calcium and D3 levels.
- Extremely affordable price per serving.
- Contains both calcium and essential Vitamin D3.
- Good elemental calcium dose.
- Calcium carbonate (oyster shell) is best taken with food for optimal absorption.
$10.00($0.02 per serving)
 iHerb | $ 10.00 |
bolt Effectiveness for goals
Yes, vitamin D is essential for the effective absorption of calcium in the intestines. Without sufficient vitamin D, the body cannot absorb calcium properly, even if calcium intake is adequate. This partnership is crucial for maximizing calcium's benefits for bone health.
Adequate calcium intake, especially when combined with sufficient vitamin D, is important for bone health and may help reduce the risk of osteoporosis. It provides the necessary minerals for bone density. However, it's one of several factors in osteoporosis prevention and management.
Calcium is a primary mineral component of bones and teeth. Adequate intake is essential for maintaining bone density throughout life and plays a crucial role in bone formation and remodeling. Consistent supply helps support strong skeletal structure.
Calcium is a crucial mineral for maintaining strong bones throughout life, acting as a primary building block for bone tissue. Adequate calcium intake helps to support and maintain bone density. It is essential for the continuous remodeling process of bones.
Calcium, especially when combined with vitamin D, is an important nutrient for maintaining bone health. Consistent intake helps support bone density, which can contribute to reducing the risk of osteoporosis. However, it is one factor among many in preventing this condition.
schedule Dosage, timing & forms
For most adults aged 19-50, the recommended daily intake of calcium is typically 1,000 mg. This recommendation may vary slightly based on age, gender, and life stage, such as during adolescence or older adulthood.
The recommended dietary allowance (RDA) for most adult men and women aged 19-50 years is 1,000 mg per day. For women over 50 and all adults over 70, the RDA increases to 1,200 mg per day. These recommendations include calcium from both food and supplements.
The two most common forms of calcium in supplements are calcium carbonate and calcium citrate. Calcium carbonate is generally more affordable and contains a higher percentage of elemental calcium, while calcium citrate is well-absorbed with or without food.
Yes, calcium supplements can interact with certain medications, including some antibiotics, thyroid hormones, and bisphosphonates. It is generally advised to take calcium supplements at a different time of day from these medications to avoid interference with absorption. Always consult a healthcare professional about potential interactions.
Calcium carbonate is the most common and inexpensive form, containing 40% elemental calcium, and is best taken with food for optimal absorption. Calcium citrate contains 21% elemental calcium, can be taken with or without food, and may be better for individuals with low stomach acid. Your specific needs may influence which form is more suitable.
health_and_safety Safety & interactions
Yes, calcium supplements can interact with several medications, potentially affecting their absorption or efficacy. These include certain antibiotics (e.g., tetracyclines, fluoroquinolones), thyroid hormones (e.g., levothyroxine), bisphosphonates, and some diuretics. It is advisable to consult a healthcare professional or pharmacist regarding potential interactions with any medications you are taking.
Yes, calcium supplements can interact with several medications, potentially affecting their absorption or efficacy. These include certain antibiotics (e.g., tetracyclines, fluoroquinolones), thyroid hormones (e.g., levothyroxine), bisphosphonates, and some blood pressure medications. It is advisable to consult a healthcare professional regarding potential interactions and timing of doses.
Common side effects of calcium supplements may include constipation, bloating, and gas. These effects are usually mild and can sometimes be alleviated by adjusting the dosage or type of calcium, or by taking the supplement with food. If side effects persist, consulting a healthcare professional is recommended.
Yes, excessive intake of calcium, especially from supplements, can lead to hypercalcemia, a condition where calcium levels in the blood are too high. Symptoms can include nausea, vomiting, confusion, and kidney problems. Adhering to the Tolerable Upper Intake Level (UL) for calcium, which varies by age, is important.
Vitamin D plays a crucial role in helping the body absorb calcium from the gut. Therefore, adequate vitamin D levels are essential for calcium to be utilized effectively by the body for bone health. Many calcium supplements include vitamin D to enhance this absorption.
Ingredients
| Ingredient | Amount per serving |
|---|---|
Vitamin D3 | 15 mcg |
Calcium | 500 mg |
Categories
Calcium 75.0
Delivers a good dose of elemental calcium with Vitamin D3, providing effective and affordable calcium supplementation.
Goals
Bone Health 75.0
Delivers a good dose of elemental calcium and includes essential Vitamin D3 for improved absorption and bone mineralization, providing solid foundational support for bone health at a very low cost.
Fitness 70.0
Offers calcium for muscle contraction and bone strength, crucial for physical performance and mitigating skeletal stress during activity. The D3 inclusion enhances this benefit.
Joint Health 65.0
Supports joint integrity indirectly through strengthening bones, with D3 further enhancing the calcium benefits for overall skeletal system support.
Recommended Alternatives
85 Value 
Calcium Magnesium Zinc + D3
21st Century
4.7
★★★★★
(97627 ratings)
Offers a comprehensive combination of calcium, magnesium, zinc, and D3 at an exceptionally low price, providing significantly more synergistic nutrients for better overall bone health value.
90 Value 
600 + D3 plus Minerals
21st Century
4.8
★★★★★
(1551 ratings)
A 21st Century product that includes calcium, D3, and a range of essential trace minerals, offering a more complete bone support formula at a superior value compared to the original.
88 Value 
Calcium + Vitamin D
Swisse Ultiboost
4.6
★★★★★
(1270 ratings)
Combines calcium citrate (better absorption) and carbonate with D3, offering a balanced and effective formula at a competitive price, delivering excellent value.
96 Performance 
Calcium Bone Maker Complex with MCH-Cal and VitaMK7
Doctor's Best
4.7
★★★★★
(6735 ratings)
A superior alternative featuring MCH-Cal and synergistic nutrients like K2 and additional minerals, offering enhanced bone density support far beyond simple oyster calcium.
98 Performance 
Raw Calcium
Garden of Life Vitamin Code
4.6
★★★★★
(4135 ratings)
A premium plant-based calcium source with a full spectrum of bone-supporting nutrients like D3, K2, and magnesium, delivering a more holistic and bioavailable approach to bone health.
93 Performance 
Liquid Cal/Mag/Zinc Natural Strawberry Flavor
Trace Minerals
4.4
★★★★★
(1954 ratings)
A liquid formula with highly absorbable calcium, magnesium, zinc, and D3, providing a more complete and bioavailable mineral profile for comprehensive bone support.
50 Budget 
600 Calcium Supplement
21st Century
4.7
★★★★★
(4047 ratings)
A basic calcium carbonate option at a similar, slightly lower price per serving, offering a highly economical choice for fundamental calcium intake.
80 Budget 
600+D3
21st Century
4.8
★★★★★
(6905 ratings)
Offers calcium carbonate with Vitamin D3 at a comparable or slightly lower price per serving, providing a good blend for bone health.
70 Budget 
Calcium 500+D3
21st Century
4.8
★★★★★
(5027 ratings)
An almost identical product from the same brand with similar ingredients (Oyster Calcium + D3), offering a cost-effective alternative.
85 Value
Calcium Magnesium Zinc + D3
21st Century
4.7
★★★★★
(97627 ratings)
Offers a comprehensive combination of calcium, magnesium, zinc, and D3 at an exceptionally low price, providing significantly more synergistic nutrients for better overall bone health value.
90 Value
600 + D3 plus Minerals
21st Century
4.8
★★★★★
(1551 ratings)
A 21st Century product that includes calcium, D3, and a range of essential trace minerals, offering a more complete bone support formula at a superior value compared to the original.
88 Value
Calcium + Vitamin D
Swisse Ultiboost
4.6
★★★★★
(1270 ratings)
Combines calcium citrate (better absorption) and carbonate with D3, offering a balanced and effective formula at a competitive price, delivering excellent value.
96 Performance
Calcium Bone Maker Complex with MCH-Cal and VitaMK7
Doctor's Best
4.7
★★★★★
(6735 ratings)
A superior alternative featuring MCH-Cal and synergistic nutrients like K2 and additional minerals, offering enhanced bone density support far beyond simple oyster calcium.
98 Performance
Raw Calcium
Garden of Life Vitamin Code
4.6
★★★★★
(4135 ratings)
A premium plant-based calcium source with a full spectrum of bone-supporting nutrients like D3, K2, and magnesium, delivering a more holistic and bioavailable approach to bone health.
93 Performance
Liquid Cal/Mag/Zinc Natural Strawberry Flavor
Trace Minerals
4.4
★★★★★
(1954 ratings)
A liquid formula with highly absorbable calcium, magnesium, zinc, and D3, providing a more complete and bioavailable mineral profile for comprehensive bone support.