There are many factors affecting the body's absorption of calcium, such as the amount of calcium intake, the ratio of dietary calcium and phosphorus, the dissociation of calcium into the intestine, the amount and type of protein in food, the physiological state of the gastrointestinal tract, etc. , can affect the absorption of calcium.
(1) Dietary calcium intake: There is a certain correlation between intestinal calcium absorption rate and dietary calcium intake. In general, as the intake of calcium in the diet increases, the amount of calcium absorbed by the intestine also increases. However, due to the saturation of the active transport process of intestinal absorption, the calcium absorption curve in the intestinal tract of normal people is obviously rising when the daily intake of about 5 mg of calcium per kilogram of body weight. When calcium intake exceeds 10 mg per kilogram of body weight per day, the amount of calcium absorbed by the intestine increases slowly.
(2) Phosphorus: The presence of phosphorus in the diet has a certain influence on the absorption of calcium. Because calcium absorption depends on a reasonable intestinal calcium and phosphorus ratio, proper phosphorus intake is very important for calcium absorption. However, when healthy adults consume more than 1 gram of phosphorus, phosphorus will form insoluble calcium phosphate with calcium ions, hindering the absorption of calcium ions in the intestine. For example, milk is very rich in content, about 3-4 times that of human milk, but due to the high phosphorus content, calcium and phosphorus ratio is not appropriate, resulting in a lot of calcium in milk is not easy to be absorbed. Unabsorbed calcium and phosphorus are present in the feces, leaving the feces dry. Milk-based infants are prone to calcium deficiency and, in severe cases, can cause rickets. Some of the better milk products on the market adopt a series of scientific and ingenious formula design, so that the ratio of calcium to phosphorus is basically 2:1, which is very close to the ratio of calcium to phosphorus in breast milk, which avoids calcium and phosphorus in milk. The disadvantages of improper ratio and low calcium absorption rate are beneficial to the absorption of calcium in the intestine.
(3) Calcium status: Ingestion of calcium disassociation has a significant effect on intestinal calcium absorption. In normal diets, calcium is present in the form of a compound that enters the stomach and is dissociated into ionized calcium by the action of stomach acid and is then absorbed in the small intestine. Modern technology activates calcium ion in the dissociation state as ionized calcium, which is active calcium. The absorption rate in the intestine is higher than calcium in the diet or traditional calcium preparations such as calcium carbonate and calcium lactate.
(4) The main physiological state of the gastrointestinal tract: The physiological state of the gastrointestinal tract has various effects on intestinal calcium absorption. The calcium that is ingested through diet is firstly affected by gastrointestinal function. Gastric acid has the function of dissolving calcium salts. Whether the concentration and quantity of gastric acid secretion is appropriate will have a direct impact on calcium absorption. This is mainly because the dietary calcium is present in the form of a compound. If the calcium salt is not resolved in the first decomposition step in the stomach, the next step in the absorption of calcium ions cannot be discussed. Because of these, organic diseases such as gastrointestinal disorders and chronic gastritis, gastric ulcers, etc., if the gastric acid secretion is insufficient, it will inevitably affect the dissociation of calcium ions in foods, directly hindering the digestion and absorption of calcium. The role of trypsin in the intestine is mainly to digest fat. If the dietary fat is too low, the secretion of bile salts is insufficient, which may delay the absorption of exogenous vitamin D. However, when the fat is completely digested, the fatty acids will form insoluble calcium soaps that are not easily absorbed by the intestinal tract with calcium, thereby reducing calcium absorption and utilization. It is for this reason that any disease of the intestine (mainly the small intestine) may interfere with the absorption of inorganic salts including calcium ions.
(5) Other factors: In addition to these factors can affect the body's absorption of calcium, there are many other can also affect the body's absorption of calcium absorption, such as oxalic acid in food and plants can be combined with calcium ions to form insoluble calcium Salt and reduce the absorption of calcium; let me inorganic salts, such as sodium and phosphate, and vitamins, antibiotics, antiepileptic drugs, diuretics and other drugs, but also can affect the body's absorption of calcium. In addition, some physiological factors also have a significant impact on calcium intake in humans. The older the age, the less calcium is absorbed by the intestine, and women are more pronounced than men. On the other hand, whether the endocrine function is normal or not determines the amount of calcium absorbed by the body. The body's hormones, such as thymotropin, calcitonin, estrogen, adrenocorticotropic hormone, and thyroid hormone, have a significant effect on the absorption of calcium in the intestine. The most closely related to calcium absorption is vitamin D and its active metabolites. The relationship between vitamin D and calcium is like fish can not be separated from water.