So then which are the best forms for supplementation? Based on their bioavailability and elemental calcium percentage, 3 forms- Calcium Citrate Malate (CCM), Calcium Bisglycinate and Calcium Phosphate are best choices for supplementation. Here’s a comparative diagram of the above 3 forms vs. Calcium carbonate
Let’s dive deeper and know more about the Calcium forms viz. CCM and Calcium Bisglycinate.
Calcium citrate malate—The best form of Calcium available
CCM is a water-soluble calcium salt of citric acid and malic acid, that was patented in late 1980’s. Its bioavailability stems from its water-solubility and its method of dissolution. When dissolved, it releases calcium ions and a calcium citrate complex. Calcium ions are absorbed directly into intestinal cells, and the citrate complex enters the body through Para-cellular absorption. An analysis of 15 randomized trials concluded that calcium citrate was absorbed 22% to 27% better than calcium carbonate, whether taken on an empty stomach or with food.
CCM has been shown to facilitate calcium retention and bone accrual in children and adolescents. In adults, it effectively promotes the consolidation and maintenance of bone mass. A study published in the Journal of Nutrition has shown that CCM supplementation led to greater bone development i.e. 44-47% as compared calcium carbonate supplementation. It is also recognized as a calcium source that does not increase the risk of kidney stones, and in fact it protects against stone-forming potential.
Calcium Bisglycinate- The highly absorbable form
Calcium Bisglycinate, is a relatively new form of Calcium and is considered as the most absorbable form. This high absorption rate is attributed to it being an amino acid chelate. Chelates are bonds that bind the mineral to chelators, in this case it being amino acid Glycine.
When food is eaten it is broken down into various compounds and molecules in the stomach and passed into the intestine for absorption. These compounds need protein carriers to ensure their absorption from the intestine in to the blood stream.
The glycine in Calcium bisglycinate serves the purpose of protein carrier and results in high Calcium absorption. Our body is very efficient at absorbing amino acids and Glycine is readily identified and absorbed across the intestinal wall.
Another factor that hinders mineral absorption from small intestine is the presence of anti-nutrients like phytates, lignans, tanins, fiber etc.). These anti-nutrients bind to the minerals and either prevent, block or limit their absorption. Calcium bisglycinate has calcium bound to two (‘bis”) glycine molecules which form strong bonds and prevent calcium from interacting with these anti-nutrients and thus ensures high bioavailability.