What is the difference between calcium citrate and calcium carbonate?

Calcium is one of the most important nutrients that human beings rely on for survival, and a deficiency of calcium can lead to a host of health problems. Especially infants, young children, pregnant women and the elderly. In order to correctly replenish calcium, we need to do some preliminary understanding of calcium tablets, the current market is commonly divided into two major categories of calcium:
First, it is inorganic calcium represented by calcium carbonate, the same belongs to the inorganic calcium also includes calcium phosphate, calcium oxide and so on.
Second, is represented by calcium citrate organic calcium, the same calcium gluconate, calcium lactate, calcium acetate also belongs to organic calcium. Next, let’s understand the difference between these two types of calcium, as well as the advantages and disadvantages.
Source of Calcium
Calcium carbonate represents inorganic calcium, which is usually found in marine organisms such as shellfish, shrimp, crab, oyster or various animal bones.
The advantage is the ease of access and the wide range of sources. Pollution exists in both marine and terrestrial environments. Heavy metals such as lead and aluminum are deposited in living organisms, leading to contamination of the calcium source; once these heavy metal ions enter the body, they will be deposited again in the human skeleton, causing irreversible damage. Our common liquid calcium is calcium carbonate.
Calcium citrate is an easily absorbed calcium extracted from citric acid, which is naturally abundant in plant fruits, making it a safer source of calcium citrate.
The difference between digestion and absorption
Calcium carbonate products are generally high in calcium, and the absorption rate of human body can reach 35%, similar to milk, which is the earliest and most widely used calcium supplement products. However, the common characteristics of these products are poor water solubility, low solubility, difficult to be absorbed, and need to consume a lot of gastric acid when absorbed in the human body.
The advantage of calcium citrate is that it can be dissolved in water and does not consume stomach acid when absorbed, so it will not stimulate the stomach and intestines and will not cause constipation and other symptoms.
Applicable people
Calcium carbonate is suitable for people with calcium deficiency, osteoporosis patients, people with good gastrointestinal function, but not suitable for people with gastrointestinal diseases, pregnant women, breastfeeding women, infants and children.
Calcium citrate is more suitable for breastfeeding mothers, people with atrophic gastritis, gastrointestinal diseases, infants, children, adolescents, pregnant women and other people because it is easy to be absorbed and does not cause gastrointestinal irritation.
Overall, calcium citrate has better solubility, assists in the absorption of other nutrients, and is less irritating to the stomach.