Calcium - Forms

Introduction

There are many different forms of Calcium.  This section outlines the various forms of Calcium in the environement and in supplements.

Concentrated Sources

 Bonemeal is not actually a form of Calcium but does contain a total of 40% Calcium (as well as Phosphate).  It is sometimes contaminated with Strontium and/or Lead.  Bonemeal is prepared from degreased Animal bones.  The form of Calcium present in Bonemeal is Hydroxapatite.

 Dolomite is a mixture of 21.7% Calcium Carbonate and (13%) Magnesium Carbonate.

 Oyster Shell Calcium is the Calcium component of Oyster Shells.  It is not a true form of Calcium however Oyster Shells contain 37% elemental Calcium (in the form of Calcium Carbonate):

 Some Oyster Shell Calcium supplements have been found to be contaminated with Lead.

Chelated Forms of Calcium

 Calcium Acetate consists of 25% elemental Calcium bound to Acetic Acid.

 Calcium Aspartate consists of 12.5% - 20% Calcium bound to 80% - 87.5% Aspartic Acid.  Between 50% and 90% of the Calcium in Calcium Aspartate is absorbed by the body.

 Calcium Bisglycinate (also known as Calcium bis-Glycinate) consists of Calcium bound to Glycine.  It presently regarded as the most bioavailable and most soluble form of supplemental Calcium.  It is 1.8 times (180%) better absorbed than Calcium Citrate and is 21% better absorbed than Calcium Citrate Malate.  It is 205 times more soluble than Calcium Citrate.  ^[1]

 Calcium Chelate (chelated Calcium) is a general term for all forms of Calcium that consist of Calcium chelated to another organic compound.  Most forms of chelated Calcium are well absorbed.

 Calcium Citrate consists of 21% to 22% Calcium bound to Citrate (Citric Acid):

 Calcium Citrate dissolves easily in Water and is regarded as being well-absorbed.

 Calcium Citrate was once regarded by many orthomolecular-oriented physicians as a candidate for being the best form of supplemental Calcium.  Recent evidence indicates that it may be the third best form of supplemental Calcium in terms of bioavailability - surpassed only by Calcium Citrate Malate and Calcium Bisglycinate.  It is significantly better absorbed compared to Calcium Carbonate.  ^[2]