Calcium usually makes up between 1.5 and 2.2 percent of the human body weight. When we consider this mineral in our body, we think of our bones and teeth -and rightly so. About 99% of calcium is found in these two tissues.
However, the remaining one percent is absolutely essential to our physiological well-being. Without calcium our blood couldn't clot and we would bleed to death from a simple cut. For our nerves to function properly and transmit messages, we must have calcium. Even the normal rhythmical contraction and relaxation of the heart is calcium dependent along with sodium, potassium and magnesium. When the level of blood calcium is low, the heartbeat may become erratic, and the heart muscles begin contracting spontaneously. Death can result. Indeed, without calcium, life as we know it would cease to exist.
To go back to our bones: even though they are rigid compared to muscles or skin, they are alive and undergoing constant remodeling throughout our adult lives. That is an extremely important concept to keep in mind when we talk about calcium nutrition because a living tissue needs a constant supply of nutrients.
Upon close examination, we will find that about thirty percent of any one of our bones is made up of organic matter; that is living cells and proteinaceous fibers. The proteinaceous fibers apparently give our bones their general shape and serve somewhat as a nucleus around which calcium bone crystals are formed.
While still fetuses, we first formed a flexible protein collagen matrix which had the general shape of a mature bone but lacked its strength and rigidity. It was essential that this matrix remain flexible to facilitate our birth. After birth, our bone-matrix became much stronger and more rigid because there was a deposition or growth of calcium phosphate crystals along the matrix, This process is known as ossification or calcification.
This bone-matrix still exists throughout adult bones and remains responsible for our bone "blueprints." It is made up of protein collagen embedded in a gelatinous substance composed mostly of sugar. In this form it is easy for the protein, like the protein of our skin or muscles, to grow and develop into the adult form. As the bone-matrix grows, more calcium crystals are laid down to accommodate increases in size of the soft tissue to the adult body. Obviously then, besides calcium, protein, and phosphorous, other nutrients are required for bone formation. Other than this matrix, there are two different types of living cells in the surface of our bones. One is called the osteoblast, the other, osteoclast. The osteoblasts are bone-forming cells; the opposite are the osteoclasts, which destroy the bone. As we said, bones are living tissues. This means that during our growth, and even during adult life, our bones are constantly being remodeled and reshaped in response to changing stresses we place on them as our weight increases or shifts. It is the responsibility of these bone cells to reform our bones from the nutrients we supply to meet theses stresses.
Each year about twenty percent of our bone calcium is dissolved by the osteoclasts and eliminated in urine, feces, and to a lesser extent through sweating. What this means is that about every five years of our adult life, the calcium in our bones has been completely replaced. In terms of daily turnover, an average adult needs approximately 600 milligrams to 700 milligrams of calcium each day to simply replace what the osteoclasts have removed. However, that doesn't include daily calcium requirements for other body needs outside the bones. These needs would have to be added to the bone requirements. Without proper chelation calcium is unable to move from the stomach and intestines to the bones. Unless it is prechelated before ingestion, calcium absorption is generally only between twenty to thirty percent of the ingested amount. The rest is eliminated.
The necessary steps for absorbing non-chelated or improperly chelated calcium, are quite similar to most other minerals. First, the calcium must be set free from its carrier. To achieve this it must be ionized through dissolving it in the stomach. If the form of calcium swallowed is insoluble, as many types of calcium are, then absorption does not take place despite our taking calcium supplement. But if the calcium does go into solution and is freed from its carrier, various substances, such as oxalic acid from fruits and vegetables or phytic acid from cereals may contribute to the formation of new insoluble compounds that are also unavailable. The formation of insoluble compounds in the stomach and intestines is one of the main reasons so much of the non-chelated or improperly chelated calcium is never utilized and is eliminated. Other factors such as the presence of dietary phosphates, the emotional stability of the individual, the pH of the intestine and the presence of dietary fats can also affect and frequently depress calcium absorption.
Now let's return to that free dissolved calcium, if there is any. Prior to absorption through our intestines, it must be chelated with amino acids. That's where Vitamin D comes in. One of its major roles in the body is to help the mucosal cells, which make up the intestinal wall lining, synthesize a special protein carrier for this calcium. The calcium is chelated to these special protein carriers and then transported across the intestinal membrane to the blood. Vitamin D is vital to the absorption of this calcium and probably accounts for our normal production of this particular vitamin even when we don't take Vitamin D supplements. Without sufficient Vitamin D to form protein carriers, the calcium absorption would be endangered.
Even though most of the calcium in our bones is not chelated, it originally must have been chelated to move from the stomach and intestines through the bloodstream to the bone area. It doesn't matter what form of calcium we swallow - bone meal, oyster shell, calcium carbonate, or any other. If the calcium is used by our body to make new bones, or whatever, it must first be chelated. For example, the concept of bone meal remaining in that form after absorption and thus automatically becoming new bone structure is incorrect. Any bone meal that becomes part of our bones must first be chelated, which renders it into a form that is no longer bone meal.
After the calcium has been absorbed into the bloodstream, it remains in the chelated state. This is how the blood transports the calcium throughout the body. The calcium is probably released by the intestinal carrier protein and re-chelated to the free amino acids already in the blood. In this form it can be carried to the storage depots (trabeculae) in the bones.
If we were to look at the bone under the microscope, we would see that none of the mineral crystals that makes up the bone is very far from the vast network of tiny capillary blood vessels. This arrangement tends to facilitate the exchange of calcium and other minerals and nutrients between bone tissues and body fluids.
As the calcium is delivered to the bones, it is stored in the trabeculae which are columns of crystalline calcium that looks somewhat like stalagmites, from the bottom of the bone cavity toward its center like strengthening braces. The delivered calcium is then released from the chelated state by the blood amino acids and becomes part of the non-chelated calcium bone crystal presumable through the help of the osteoblasts. At the same time the calcium, which is dissolved from the bone by the osteoclasts is picked up by amino acids and chelated in the blood prior to its removal and deposition into body wastes. Normally, when you consider calcium losses in the stomach and the intestines, at least 800 milligrams of calcium are needed each day simply to replace the approximately 320 milligrams that are lost. The current U.S. recommended daily allowance (U.S.R.D.A.) for calcium is 1000 milligrams, well above the minimum needed. The important concept to remember is that unless the calcium is first chelated it isn't going to become part of our bone or teeth. However, not all calcium chelates are equally acceptable to the body. As Dr. Tony Cunha once wrote, "Mineral elements may be chelated by a compound which will either increase or decrease its (the mineral's) availability." We must conclude that the calcium should be chelated with a natural substance that can be found in the body. In other words, it must be chelated with amino acids from hydrolyzed protein.
Even though we select the right chelating agent for the calcium, there are still many other considerations that will also affect how much of the calcium is absorbed. By definition, the role of the chelate is to protect the mineral by surrounding or suspending it within a chelating agent which, in this case, we have already determined for nutritional purposes should be two or more amino acids. When the calcium is surrounded or chelated it is prevented form entering into chemical reactions which may make it unabsorbable. That is the function of the chelate.
Even though the calcium is chelated with hydrolyzed protein, it can still be unavailable to the body if manufactured improperly. For example, in research done jointly by Albion Laboratories and a university, it was shown that when radioactive calcium was correctly chelated and held with the right degree of tightness within the amino acids, absorption was almost 50 percent greater with one chelate than with another.
There is one last consideration in calcium absorption. Dr. Helen Guthrie has reported that calcium is more readily absorbed when it is in an acid environment rather than alkaline. Unfortunately, our bodies are not designed to accommodate calcium's needs. As our food moves out of the acid pH of the stomach into the small intestine, the pH becomes alkaline. This in turn reduces the calcium absorption and accordingly increases the amount of calcium excretion. Recently this problem was overcome with the development of a new approach to chelation through a special chelating technique. The calcium is pH protected so that it isn't subject to the fluctuations in the pH of our bodies. This newest development allows more of the calcium to be absorbed an utilized by the body than non-protected chelates even if they are amino acid chelates. Studies have shown that due to the high turnover of calcium in our bodies, many of us have definite problems in obtaining sufficient calcium for our needs. This may be due to the lack of dietary intake or our inability to absorb sufficient calcium from our diets. One of the absorption problems may result from difficulty in chelating sufficient calcium with dietary amino acids. When this problem extends over a long period, our bones can become brittle and are easily broken. Other symptoms of a calcium deficiency may also appear.
Fortunately, science has developed new techniques to improve the availability of our dietary calcium through the process of chelation with amino acids from hydrolyzed protein. Consequently, over the years we have developed a superior calcium chelate which is protected against the absorption robbing pH changes that normally occur in our bodies. We are now one step closer to perfection.
From Bestways March 1990
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