Calcium Citrate (CAS 813-94-5) is the calcium salt of citric acid, represented by the chemical formula Ca₃(C₆H₅O₇)₂ with a molecular weight of 498.43 g/mol. This organic calcium compound is widely recognized for its superior absorption and digestive tolerance compared to other calcium forms, making it a preferred choice for dietary supplements and food applications.
What is Calcium Citrate?
Calcium citrate is an organic calcium salt produced through the reaction of citric acid with calcium hydroxide or calcium carbonate. Unlike inorganic calcium compounds, calcium citrate offers excellent bioavailability and is particularly well-tolerated by individuals with sensitive digestive systems. As a food additive, it is designated as E333 and serves multiple functions in food processing.
This compound exists in various hydrate forms, with the anhydrous and tetrahydrate forms being most common in commercial applications. The unique chemical structure of calcium citrate allows for efficient calcium absorption even in individuals with reduced stomach acid production.
What Are the Benefits?
Calcium citrate offers numerous health benefits that make it a preferred calcium supplement choice:
Superior Bioavailability
One of the most significant advantages of calcium citrate is its excellent bioavailability. Studies have shown that the absorption of calcium citrate is comparable to or even better than calcium carbonate, especially when taken with food. Unlike calcium carbonate, which requires stomach acid for optimal absorption, calcium citrate is absorbed independently of stomach acid levels.
Enhanced Digestive Tolerance
Calcium citrate is gentler on the digestive system compared to other calcium forms. It does not cause the constipation, bloating, or stomach irritation commonly associated with calcium oxide or carbonate supplements. This makes it ideal for individuals who experience digestive discomfort with traditional calcium supplements.
Bone Health Support
Calcium citrate effectively increases plasma calcium levels, which helps maintain optimal bone mineral density. By reducing the secretion of parathyroid hormone (PTH), it minimizes calcium loss from bones, supporting long-term skeletal health. This makes it particularly valuable for preventing osteoporosis and supporting bone regeneration.
Cardiovascular Health
Adequate calcium intake through supplements like calcium citrate may contribute to cardiovascular health. Calcium plays a role in maintaining normal blood pressure levels and supporting proper heart muscle function.
What Are the Uses?
Calcium citrate (CAS 813-94-5) serves diverse applications across multiple industries:
Dietary Supplements
As a premium calcium supplement, calcium citrate is used in various supplement formulations including tablets, capsules, chewables, and liquid preparations. Products like Citracal and Caltrate utilize calcium citrate as their primary calcium source due to its superior absorption profile.
Food Additive
In the food industry, calcium citrate functions as:
- Sequestrant: Binding to metal ions to prevent oxidation and maintain food quality
- Buffering agent: Maintaining pH stability in food products
- Preservative: Extending shelf life of processed foods
- Nutrient fortifier: Enriching foods with bioavailable calcium
Pharmaceutical Applications
In pharmaceutical formulations, calcium citrate serves as an excipient that:
- Improves the bioavailability of calcium in medications
- Enhances the solubility of active pharmaceutical ingredients
- Provides stabilization in various drug formulations
- Supports treatments for osteoporosis and calcium deficiency conditions
Safety and Side Effects
Calcium citrate is generally well-tolerated and considered safe for most individuals when used as directed. However, some users may experience mild side effects:
- Common side effects: Constipation and upset stomach may occur in some individuals, though these are less frequent compared to other calcium forms
- Serious side effects: Rare but may include symptoms like nausea, vomiting, or loss of appetite
- Drug interactions: Calcium citrate may interact with certain medications including antibiotics, thyroid medications, and bisphosphonates
It is recommended to take calcium citrate with food for optimal absorption and to maintain adequate vitamin D levels. Individuals with kidney stones or hypercalcemia should consult a healthcare professional before using calcium supplements.
Chemical Specifications
| Property | Value |
| CAS Number | 813-94-5 |
| Chemical Formula | Ca₃(C₆H₅O₇)₂ |
| Molecular Weight | 498.43 g/mol |
| Appearance | White, odorless crystalline powder |
| Solubility | Soluble in water |
| Food Additive Number | E333 |
Frequently Asked Questions
Is calcium citrate better than calcium carbonate?
Calcium citrate offers several advantages over calcium carbonate, particularly for individuals with low stomach acid or digestive sensitivities. While both provide comparable calcium absorption when taken with food, calcium citrate is better tolerated and does not require stomach acid for absorption.
How much calcium citrate should I take daily?
The recommended daily calcium intake varies by age and gender, generally ranging from 1,000-1,200 mg for adults. Since calcium citrate contains approximately 21% elemental calcium, supplementation amounts should be calculated based on individual needs and dietary intake.
Can I take calcium citrate with other medications?
Calcium citrate may interact with certain medications. It is recommended to take calcium supplements at least 2-4 hours apart from other drugs. Consult a healthcare provider for personalized guidance on medication interactions.
Why Choose Our Calcium Citrate?
We provide premium quality Calcium Citrate (CAS 813-94-5) that meets international standards for food, pharmaceutical, and supplement applications. Our product features:
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Contact us today to learn more about our Calcium Citrate products and how they can benefit your applications.
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