Sisu Liquid Cal Mag Citrates - Blueberry Parfait Flavour - Calcium citrate is much more bioavailable than other forms. It is made from calcium carbonate, and has been processed so that each molecule of calcium is bound to a molecule of citric acid. This enhances the stomach’s ability to break down the calcium and transfer it to the blood for distribution to the bones and teeth. This becomes increasingly important as we age. The magnesium in Sisu Cal Mag Citrates is in the highly bioavailable citrate form. Calcium and magnesium also regulate heart contractions and support healthy blood pressure, so this supplement supports several aspects of health with every spoonful.