Calcium
CALCIUM was one of the first substances known to be essential in the diet. By 1842, a French scientist had proven experimentally that the shortened lifespan of pigeons appeared linked to the bird's severely depleted bones. When calcium carbonate was given to the pigeons, both problems were prevented. Even though this was known to happen in animals, experiments on humans were not undertaken until the mid 1900's.
There is more calcium than any other mineral in a child's body. An adult's body contains roughly 2%, or 2 pounds, of its total body weight in calcium. By far, the vast majority of the mineral (99%) is found in bones and teeth, with the remaining 1% (about two-thirds of a tablespoon) in soft tissues and body fluids serving other functions not related to bone structure. The body continually adjusts the amount of calcium in the blood in order to keep it at an exact level.
The calcium ion is the most sensitive chemical regulator of human cellular activity known. Even the slightest difference in the concentration of calcium can influence body cells and organs, causing a skipped heart beat, for example. Should concentrations become too high in a cell, toxic oxygen forms destroying the cell. But, in order for calcium to be a wonder mineral controlling bodily functions, other factors must be present, including a great many nutrients that interact with this mineral, affecting its absorption as well as its losses in the urine.
For example, the cardiovascular network relies heavily on calcium and magnesium. Without Vitamin D, calcium cannot be absorbed at all. However, an oversupplementation of Vitamin D is more likely to cause high blood calcium than a high intake of calcium alone. Boron plays a role in preventing calcium loss and may help increase the levels of natural estrogen, which, in turn, helps to conserve calcium. Plant estrogens, such as those found in soy products, are the current center of attention in that area. In order for calcium to be transported to bone marrow, it needs to be in balance with phosphorus. When there is not a balance, the bone marrow becomes starved for calcium, and osteoporosis develops.
Calcium is required for heart muscle contraction and in regulating the heart beat. It also assists in the utilization of iron, helping it pass through cell walls, thereby providing strength and energy. In children, it helps to alleviate the muscle and bone pain commonly referred to as "growing pains." Calcium quickens the reflexes by aiding the nervous system in impulse transmission and helps to alleviate insomnia. It is also an important mineral in blood coagulation and for the activation of numerous enzymes.
Proper absorption of calcium is prevented by a number of factors, including the consuming of large quantities of fat, oxalic acid (found in chocolate and rhubarb), and phytic acid (see separately). Calcium loss is accelerated about the time of menopause, but then slows down again. The same thing happens during peak times of pregnancy and lactation as well as of childhood growth.
Successful lobbying has ingrained the belief that milk consumption is vital to the prevention of osteoporosis. Yet, populations in developing countries appear to have less risk from fractures than those in milk-drinking countries, despite their low body weights and calcium intakes from milk. They also smoke less, drink less alcohol, do more physical work, and consume less protein, salt, and sugar. Studies have shown that female meat-eaters had lost 35% of their bone mass by 80 years of age while female vegetarians had lost only 18%.
Osteoporosis does not happen solely from a lack of calcium nor do calcium supplements alone correct the problem. At least forty per cent of postmenopausal women have extrememly low levels of stomach acid needed to aborb calcium. It is these people who can absorb only about 4% of an oral calcium carbonate, while people who have adequate amounts of the acid absorb about 22%.
In order to boost sales, some antacids are advertized as being a good sources of the mineral. The calcium used in antacids is not easily absorbed, in addition to having another problem. Many antacids contain aluminum, which inhibits the absorption of calcium, as well as causing toxicities of their own. Maalox, Amphogel, Gelusil, and Mylanta contain as much as 200 mg. of aluminum per tablet, and buffered aspirin can contain 10-52 mg. per tablet. When calcium carbonate, the kind found in Tums or oyster shells, for example, comes in contact with stomach acids, it is converted to calcium chloride, which is better absorbed; but this also improves aluminum absorption. In addition, antacids are designed to lessen stomach acid, thereby defeating the purpose of utilizing the calcium from this source.
Beer, alcohol, coffee, tea, soft drinks, salt, and nicotine are the bone's worst enemies, directly interfering with calcium absorption. Sugar is also a major cause of calcium deficiency and is known to deplete the body stores of phosphorus. Phosphorus and magnesium are essential for the assimilation of calcium; and, when there are imbalances of either, calcium is excreted from the body rather than utilized. High phosphorus foods cause calcium to form insoluble compounds that lead to inadequate absorption. Chicken contains more phosphorus than even lean cuts of red meats; and, consuming large quantities of poultry, seafoods, soft drinks, pork products, and processed foods significantly contribute to a phosphorus-calcium imbalance.
Not only does sugar have a devastating effect on calcium levels but caffeine does also. Because of caffeine's diuretic properties, it doubles the rate of calcium excretion, causing the parathyroid gland to secrete the hormone responsible for drawing calcium from the bone in order to keep the blood calcium level within normal limits. In addition, coffee not only contains caffeine but twenty-nine other acids that cause calcium to be drawn from the bones in order to neutralize them.
When too much protein is consumed, the breakdown and excretion of excess sulfur-containing amino acids causes the urine to become more acidic, forcing it to carry out more calcium along with the excess proteins. Meat, poultry, fish, and eggs are concentrated sources of sulfur-containing amino acids. Plant foods do contain these same sulfur amino acids, but they are less concentrated sources of total protein, and so the excretions are less likely to occur. To put it simply, the more protein that is eaten, the more calcium that is secreted and lost from the body. If there is insufficient calcium in the diet, or if it is lost because of high protein diets, the body will glean calcium from anywhere it can in order to satisfy its needs. That gleaning usually comes from the bones, contributing to osteoporosis. Another helpful plus from plants is progesterone, which has proven to play a vital and unique role in treating osteoporosis by actually reversing the damaging bone loss caused by the disease. Weight- bearing exercises at least three times a week play a significant role in retaining calcium as well.
For generations, milk has been touted as being the only good source of calcium and a major contributor in the prevention of osteoporosis, when, in fact, it takes a very high consumption in order to obtain enough calcium from milk to do any good. Processing tends to bind the calcium, rendering it unusable by the body. In addition, many erroneously believe that there are few, if any, alternatives to milk to gain calcium. Green vegetables are the best plant sources of usable calcium, but they are rarely considered or advocated. Lime-processed tortillas are also a good source of calcium. To give a general idea, the following is a list of the percentages of calcium that is absorpted from certain foods: cooked green vegetables (50-70%), milk (32%), tofu (31%), almonds/sesame seeds (21%), cooked red/white/pinto beans (17%). Cooked spinach/beet greens/chard/and rhubarb are only 5% absorbed because of the oxalate content in these foods.
Several years ago, a specialist at a symposium in Denmark stated that more women die from osteoporosis-related fractures than from cancers of the breast, cervix, and uterus combined. In the US, hip fracture health care costs up to $10 billion annually and causes at least 200,000 deaths. One out of three women and one out of six men after retirement age will suffer a hip fracture. The women most likely to be at risk are those who are relatively inactive, have small frames, have kidney disease, have had their ovaries removed before the age of forty, have a family history of osteoporosis, or are of Northern European, Latin, or Asian descent, plus the fact that, for various reasons, the older a person becomes, the more difficult it is to absorb calcium.
There is little doubt that the typical western diet is responsible for the devastating effects of osteoporosis -- not to mention causing many other health problems. High in fat, sugar, protein, sodium, and phosphorus, 'western cuisine' causes calcium to flush out of the body unabsorbed, and, therefore, never used. After spending millions of dollars on foods destructive to the body, more is spent on supplements to undo the damage.
If the body does absorb too much calcium, the following problems can occur: 1) hypercalcemia (too much calcium in the blood); 2) too much in the urine, which increases risk of kidney stones; 3) calcification of various body tissues, especially in the kidneys; 4) osteosclerosis (excessively dense bones). But the odds of these conditions occurring are far less than one would expect and are usually the result of oversupplementation and/or poor absorption, causing the mineral to accumulate in unwanted areas of the body.
RDA varies, depending on the country. The WHO (World Health Organization) has the lowest rate of recommendation while the US advises the highest. The National Institute of Health recommends that 1 gram of calcium be taken per day for premenopausal women and 1500 mg. per day for post-menopausal women. However, be aware that an excessive intake of over 2000 mg. can lead to hypercalcemia. Studies have shown that 1250 mg. of calcium per day for two to three months slowed abnormal cell division in the colon which may be attributed to calcium's ability to detoxify carcinogenic bile acids. Other studies have shown that those with hypertension have lowered calcium levels and a daily supplementation of 1500 mg. significantly lowered the blood pressure. The ratio for best calcium absorption should be two times the amount of calcium as to magnesium and 2.5 times the rate as to phosphorus. Research has shown that calcium is absorbed far more efficiently when it is consumed in many small doses.
Note: To test whether your supplement is capable of digesting well, place a tablet in some vinegar and leave for thirty minutes. If it has broken into pieces during that time, it is a good indication that it will do the same internally, providing that there is sufficient hydrochloric acid available to do the job. (Septic tank companies remark on how many intact multivitamin supplements they find during their course of cleaning).
Summary:
Names include: Ca, Ca+2, Ca++, and element 20. Often listed commercially as "calcium carbonate" (which is chalk, the starting compound for the production of commercial calcium salts), "calcium glycerophosphate", "calcium phosphate", "calcium pyrophosphate, and "calcium sulphate" (which is plaster of paris).
Deficiency symptoms include: cramps, emotional agitation, nervousness, insomnia, headaches, cadmium and lead retention, grinding teeth, muscle spasms/twitching, increased muscle/tendon strain, convulsions, thinning/softening bones, softening teeth, late tooth dentition, diminished blood calcium, cold hands and feet, numbness, hydrocele (a painless swelling of the scrotum), night sweats, varicose veins, carbuncles, skin eruptions, deep abscesses, chronic oozing ulcers, cracked skin, sore breasts.
Toxicity symptoms include: decreased gastrointestinal tone, kidney failure, emotional deterioration, increased blood calcium.
Inhibitors include: fats, oxalic acid, phytates, aspirin, barbiturates, strong sedatives, aluminum, neomycin, excess protein/salt/alcohol consumption, smoking, caffeine, and prolonged inactivity.
Helpers include: Vitamins A, C, D, and F, boron, iron, magnesium, phosphorus, strontium, and hydrochloric acid.
Percentages of elemental calcium found in various sources: C. carbonate (40%); C. Phosphate-tribasic (38%); C. Phosphate-dibasic (23%); Bonemeal (32%); Dolomite (22%); C. citrate (21%); C. lactate (13%); C. levinulate (13%); C. gluconate (9%); C. gluceptate (8%); C. glubionate (6.5%).
Calcium supplementation most often used:
1) Bonemeal is the crushed bones of animals and does not absorb easily within the body. It also contains large amounts of phosphorus and is not a choice of vegans.
2) Calcium lactate is a milk derivative and also is also not a choice of vegans, but it is easier to absorb than bonemeal.
3) Calcium gluconate is derived from a vegetable source and is more potent than the calcium lactate.
4) Dolomite is a natural form of calcium and magnesium and requires no Vitamin D for assimilation. However, it is poorly absorbed and usually has lead contamination.
5) Calcium citrate and calcium citrate malate are highly absorbable forms that require a minimum of hydrochloric acid for its absorption. These forms are better for the elderly and those with gastrointestinal disorders that diminish hydrochloric acid secretions.
6) Calcium gluconate and calcium hydroxyapatite are also good forms, but calcium carbonate, dolomite, and bone meal are the poorest forms for absorption.
7) Chelates and chlorides are the most expensive forms, but there is little evidence to support that they are absorbed better than cheaper forms.
