An adult's body contains two to three pounds of its total body weight in calcium, making it the most abundant mineral in the body. Ninety-eight percent is found in bones, 1% in teeth, and the remaining 1% (about two-thirds of a tablespoon) is found in soft tissues and body fluids. The body continually adjusts the amount of calcium in the blood in order to keep it at an exact level.

      Calcium is a critical mineral in the development and maintenance of hard tissue such as bone and teeth.  It is also required for heart muscle contraction and regulating the heart beat. It assists in the utilization of iron, helping it pass through cell walls.  Calcium quickens the reflexes by aiding the nervous system in impulse transmission and helps to alleviate insomnia.  It is an important mineral in blood coagulation and in the activation of numerous enzymes.

       The body strives to maintain certain ratios between calcium and other minerals in order to maintain homeostasis.  For example a blood ratio of approximately 2:1 calcium over phosphorus is necessary for the body to function properly.  If there is too much phosphorus coming into the body from the diet, the body will draw calcium from the bones into the blood to maintain this ratio.  Since the typical western diet is high in phosphorus compared to calcium, this diet becomes a serious dynamic in the development of osteoporosis.  The western diet often has a reverse ratio of 2:1 phosphorus over calcium and often much higher.  This has led to a dramatic increase in osteoporosis and other hard tissue problems. Phosphorus is found in high amounts in animal products and in processed and refined foods.


       Elemental calcium is inorganic as it does not contain carbon which is what defines a substance as organic. However, most calcium is bound to an organic agent and therefore is considered an organic substance.  For example, the most common form of calcium is calcium carbonate where you have inorganic elemental calcium bound to organic carbonic acid which is made from water and carbon dioxide.  This form of calcium is generally 40% calcium and 60% carbonic acid.  It is found in limestone, marble, dolomite rock, and egg and oyster shells.  Calcium carbonate is the form most often used in calcium supplements as it is the least expensive to obtain.  Supplements containing pure calcium carbonate require more hydrochloric acid (HCL) in the stomach in order to be absorbed.  This is why this form is used in antacids such as Tums as it will “soak up” stomach acid.

       Some antacids are advertised as being good sources of calcium.  While they are good sources of calcium, their calcium is in the form of calcium carbonate which is difficult to absorb due to its requirement for large amounts of hydrochloric acid. Many antacids contain aluminum which inhibits the absorption of calcium, as well as, creating toxicity for the body. Some antacids, such as Maalox, and Mylanta, contain as much as 200 mg. of aluminum per tablet. When calcium carbonate comes into contact with hydrochloric acid, it is converted to calcium chloride which is better absorbed but it also enhances aluminum absorption in the case of antacids.  

       Calcium found in vegetables is in the form of calcium gluconate where inorganic calcium is combined with gluconic acid produced from the oxidation of glucose. Calcium in this form contains 9.3% of actual calcium.  The gluconic acid in this compound will also increase the bio-availability of dietary or supplemental magnesium.  Calcium from animal sources is in the form of calcium lactate and consists of 12.5% calcium bound to lactic acid. 


      Bone Meal contains around 40% of a form of calcium called hydroxyapatite along with other minerals. Hydroxyapatite closely resembles the form of calcium found in the body’s bones and teeth.  It is into this form the body processes dietary calcium in order for it to be utilized by the body in building and maintaining hard tissue.  Hydroxyapatite can be obtained in supplemental form. As a supplement, hydroxyapatite is generally derived from bones of bovine animals.  A negative with bone meal is that it sometimes has been found to be contaminated with lead and other heavy metals. 

       Dolomite, a pale colored mineral, is a mixture of 21.7% calcium carbonate and 13% magnesium carbonate.  Oyster shells contain 37% elemental calcium in the form of calcium carbonate.  Some oyster shell calcium supplements have been found to be contaminated with lead.  Di-Calcium Phosphate consists of 29.5% calcium bound to phosphorus.  Calcium aspartate consists of 12.5% - 20% elemental calcium bound to 80% - 87.5% aspartic acid.  Between 50% and 90% of the calcium in calcium aspartate is absorbed by the body.  Calcium citrate consists of 21% to 22% calcium bound to citric acid.  Calcium citrate dissolves easily in water and is regarded as being well-absorbed. Those with insufficient production of HCL will absorb approximately 45% of the calcium content of calcium citrate supplements. 


       Calcium is widely available in the food chain being found in a wide range of animal and plant based products.  Dietary calcium must be made soluble in the stomach and remain in a soluble state as it enters the duodenum, the first part of the small intestine which is the primary site of calcium absorption.  This solubility in the stomach is made possible by the action of HCL.  In the small intestine the calcium must be chelated (attached to) calcium binding substances in order to be absorbed and utilized by the tissues. It is interesting to note that the absorption of calcium decreases as calcium intake increases.  For example, one study demonstrated that an average of 60% of a daily supplement of 600 mg of calcium citrate was absorbed, while an average of 55% of a daily supplement of 1,200 mg of calcium citrate was absorbed.  A low-calcium diet (300 mg of calcium per day) resulted in an average 71% absorption.  The body has a way of closely regulating calcium absorption.

       In addition to HCL in the stomach, vitamin D is absolutely essential for the utilization of calcium. Without enough vitamin D, calcium will not be utilized!   As stated above, 98% of calcium is used to build and maintain bone tissue.  Calcium, however, does not work alone in this process.  The macro-minerals magnesium and phosphorous along with such trace minerals as silicon, boron and manganese are also very important along with vitamin K. 


       It is best to get your calcium from food where it is naturally chelated to various carrying agents that promote its absorbability and utilization by the body.  It is also wise to eat more foods that have high calcium to phosphorous ratios.  As discussed above, two much phosphorous in the diet leads to the body robbing calcium from the bones in order to maintain necessary blood levels of calcium.  Even though more calcium supplements are taken by Americans than by those in other parts of the world, we still have the highest levels of osteoporosis and bone fractures than any other country.  This is because the typical American diet is way too high in phosphorous.  It is high in phosphorous because of our high consumption of animal products along with processed and refined foods which are high in phosphoric acid based compounds.  Meats in general have a 10 to 200 calcium to phosphorous ratio.  Even cow’s milk, which is a good source of calcium, has almost as much phosphorous as calcium with a ratio of 118 calcium to 93 for phosphorous.  Vegetables, on the other hand, are generally higher in calcium than phosphorous.  For example, leaf lettuce has a ratio of 68 to 25, turnip greens 246 to 58, kale 149 to 93, spinach 93 to 51 and broccoli 103 to 78.  Fruit, nuts and seeds, legumes and grains generally have more phosphorous than calcium.  EAT VEGETABLES and eat less animal products. Stay away from processed and refined foods.  Eliminate soda water which is high in phosphoric acid.


       If you feel your diet is not giving you the calcium you need, it is wise to add a high quality calcium supplement to your diet.  I would stay away from strict calcium carbonate supplements as they have been shown to not be well absorbed.  This would include typical mass market calcium supplements often made from oyster shells.  It is best to supplement with a chelated form of calcium where the manufacturer has taken elemental calcium and attached it to a carrying agent such as an amino acid or some other acid that is common to the body such as citric acid.  Calcium citrates are felt to be very well absorbed and do not require a lot of HCL in the stomach.  Production of HCL diminishes as we grow older and therefore a calcium citrate and other chelated forms of calcium can be helpful to older consumers.  We carry a variety of chelated calcium products at Milk ‘N Honey.  Some of the best calcium supplement products contain calcium derived from food sources and are naturally combined with many other nutrients necessary for proper calcium absorption and the building of hard tissue. At Milk ‘N Honey we carry a high quality calcium supplement called Bone Strength Take Care from the company New Chapter.

       The calcium complex in Bone Strength Is derived from a specific plant form called Lithothamnion Calcareum, sustainably harvested from pristine shores along the Icelandic coastline. Much like organic vegetables, this sea plant is allowed to mature naturally and then sustainably harvested to deliver its optimal nutritional value.

       Calcium must be completely dissolved in order to be absorbed. The plant-based calcium found in Bone Strength Take Care grows in a honeycomb structure and is extremely porous, which dramatically increases the calcium’s surface area. Stomach acid can then come into greater contact with the calcium, making it easy to dissolve. Calcium carbonate sourced from limestone has a much smaller, rocky surface area and is more difficult to dissolve.

       In addition to whole-food calcium, magnesium and trace minerals, Bone Strength is formulated with  a proprietary blend of whole-food vitamins designed to optimize calcium absorption and utilization. This blend provides a highly bioavailable, bioactive, and long-lasting form of natural Vitamin K2 (MK-7). Vitamin K2 is the most active form of Vitamin K in bones and arteries. This key nutrient helps put calcium into our bones where we need it, and helps keep calcium out of our arteries, where we don’t.  This complex of nutrients includes Vitamin D3 which is important for calcium absorption and has been found to aid in bone support and function. New Chapter creates whole-food complexed Vitamin D3 by culturing the nutrient with probiotics and organic whole foods. 

       Another high quality calcium we carry is Vitamin Code Raw Calcium from Garden of Life.  This product also provides very absorbable calcium along with many other nutrients necessary for maintaining the health of bone tissue. 


       In general, calcium absorption becomes less efficient as we age. During infancy and childhood, 50-70 percent of the calcium ingested may be absorbed whereas an adult might use only 30-50 percent of dietary calcium in his or her body.  Some of this reduction in absorption may be the result of reduced need by the body while some reduction is due to less HCL production as we age. Since absorption of calcium is so variable, it is difficult to determine the right amount of calcium for all people. Many dynamics regarding absorption come into play.  With the average absorption rate ranging from 30-50 percent for adults, the 800 mg. RDA may not be enough to prevent osteoporosis and other calcium deficiency problems. Possibly half of the population is getting less than the RDA, and many people are consuming a diet that supplies less than two-thirds of the RDA for calcium.

       Research indicates a daily intake of 1,000 mg. (1 gram) is recommended for adult men and women. Pregnant and nursing women should be getting 1.5 grams per day of calcium. The calcium intake suggested for postmenopausal women has recently been changed to 1.5 grams per day with some additional magnesium and vitamin D because of higher elimination and decreased absorption in postmenopausal women.

       People with high-protein, high-fat, or high-phosphorus diets need even more calcium. When we increase calcium, we should also increase our magnesium intake, keeping it at about one-half the calcium supply. Magnesium helps calcium stay more soluble, and thereby may reduce the risk of kidney stone formation and other calcifications.  Many Americans are deficient in magnesium.  Magnesium is largely found in green foods.