Name: China Supplier High Quality Calcium citrate tetrahydrate CAS 5785-44-4 with best price
Brand: Wuhan Fortuna Chemical Co., Ltd.

Calcium Citrate Tetrahydrate is the calcium salt of citric acid. Let's break down its name:

Calcium Citrate: This refers to the compound formed when calcium (Ca²⁺) binds with citrate, the ion from citric acid. The base chemical formula is Ca₃(C₆H₅O₇)₂.
Tetrahydrate: This indicates that four water molecules (·4H₂O) are incorporated into its crystal structure. This is the most common form found in supplements and food.

In simple terms, it's a specific molecule that delivers calcium in a form that the body can easily use.

Key Properties:

Appearance: A fine, white, odorless powder.
Solubility: It has low solubility in water but is highly soluble in dilute acids. This property is crucial for its behavior in the body.
Acidity: It has a neutral to slightly alkaline pH when dissolved.

Common Uses of Calcium Citrate Tetrahydrate

Its primary use is as a source of calcium, and its unique properties make it preferable to other calcium forms (like calcium carbonate) in many situations.

1. Dietary Supplements (The Most Common Use)

This is the flagship application for calcium citrate. It is one of the most popular forms of calcium found in supplement pills, capsules, and chewables.

High Bioavailability without Food: This is its biggest advantage. Unlike calcium carbonate, which requires stomach acid for absorption, calcium citrate does not. It can be absorbed effectively even when taken on an empty stomach or by individuals with low stomach acid.
Ideal for Specific Populations:

Older Adults: Stomach acid production often decreases with age, making calcium citrate a better choice.
People taking Acid-Reducing Drugs: Individuals using medications for acid reflux or ulcers (like PPIs or H2 blockers) benefit from calcium citrate.
People with Inflammatory Bowel Disease (IBD) or Absorption Issues: Its soluble nature can make it easier to absorb.

2. Pharmaceutical Applications

Beyond being a simple supplement, it is used in the pharmaceutical industry as an active ingredient and an excipient.

Active Pharmaceutical Ingredient (API): It is the direct source of calcium in prescribed calcium supplements.
Excipient: It can be used as a buffering agent or a source of ions in certain pharmaceutical formulations.

3. Food and Beverage Additive

Calcium Citrate is approved as a food additive (E333(iii)) and serves several functions:

Fortification: It is used to add calcium to foods and beverages that don't naturally contain it, such as:

Fruit juices and plant-based milks (soy, almond, oat)
Cereals and energy bars
Baby formula

Chelating Agent / Preservative: The citrate ion can bind to metal ions that cause spoilage, helping to preserve food quality and flavor.
Firming Agent: It can help maintain the firmness of canned fruits and vegetables.
Buffer: It helps control and stabilize the pH in certain food products.

Calcium Citrate vs. Calcium Carbonate: A Key Comparison

To understand its uses better, it's often compared to the other common form, Calcium Carbonate:

Feature	Calcium Citrate Tetrahydrate	Calcium Carbonate
Elemental Calcium	~21% (less calcium per gram)	~40% (more calcium per gram)
Absorption	Does not require stomach acid. Can be taken with or without food.	Requires stomach acid for absorption. Must be taken with a meal.
Best For	Older adults, people with low stomach acid, those on acid-reducers.	Generally healthy individuals with normal stomach acid who take it with meals.
Cost	Typically more expensive.	Typically less expensive.

What "Elemental Calcium" Means: This is the actual amount of usable calcium in the supplement. A 500 mg pill of calcium citrate contains only about 105 mg of elemental calcium (21% of 500 mg), meaning you may need to take more pills to reach your daily requirement compared to carbonate.

Summary Table of Uses

Field/Industry	Primary Function	Examples
Dietary Supplements	Source of Bioavailable Calcium	Calcium pills, chewables, gummies; especially for those with low stomach acid.
Pharmaceuticals	Active Ingredient & Excipient	Prescription calcium, buffering agent in medications.
Food Technology	Fortifier, Preservative, Firming Agent (E333(iii))	Fortified juices & plant milks, canned foods, cereals.

Safety Note:
Calcium Citrate Tetrahydrate is generally recognized as safe (GRAS). However, the total calcium intake from all sources (diet and supplements) should be considered. The Tolerable Upper Intake Level (UL) for adults is 2,000-2,500 mg per day. Excessive intake can lead to kidney stones or other issues. It's always best to consult a healthcare provider to determine the right type and dose of calcium for your individual needs.