There is a wide range of calcium supplements on the market today. The more common calcium supplements include calcium carbonate, calcium citrate, calcium lactate, and calcium gluconate. There are also solid forms such as tablets, powders, punches and capsules, and liquid forms such as water and emulsions.
Solid Calcium
Calcium carbonate is the most common solid form of calcium in hospitals and on the market, typically containing 40% calcium, and can be taken by most people. And calcium carbonate tablets are usually marketed as a combination with some vitamin D, which can be supplemented with both elements.
But calcium carbonate also has some side effects, mainly in the gastrointestinal tract:
- Calcium carbonate neutralizes stomach acid to produce calcium chloride, which overwhelmingly interacts with intestinal bicarbonate and phosphate to produce calcium carbonate and calcium phosphate that are difficult for the intestines to absorb, leading to constipation.
- Gastric acid reaction releases carbon dioxide leading to flatulence.
- Calcium ions acting on the gastric mucosa stimulate the release of gastrin, causing increased rebound gastric acid secretion.
Calcium citrate, calcium gluconate, and calcium lactate are all classified as organic acid calcium and are characterized by good water solubility and relatively low gastrointestinal irritation compared to regular inorganic calcium tablets, but contain slightly lower calcium content and are not recommended for routine use.
Liquid calcium
Liquid calcium is an emulsion calcium supplement made from milk and concentrated by ultra-low temperature freezing extraction. Solid calcium must be broken down by stomach acid to free the calcium from the complex. Generally, solid calcium has the potential to hurt the stomach and has discomfort such as gas production and regurgitation. In comparison, the calcium ion free procedure of liquid calcium is more direct and safer.
It is worth noting that the absorption of liquid calcium is comparable to that of solid calcium, and the key to calcium supplementation is to get enough. Patients should look at the dose of elemental calcium contained when choosing a calcium supplement and should also consume adequate amounts of vitamin D along with the calcium supplement.