What is calcium and what does it do?
Calcium is an important mineral for the optimal functioning of many body systems, and a building block in our bones and teeth. Calcium also protects the body from heavy metal toxicity by competing for absorption against lead. Calcium ions are involved, at the cellular level, with the folding structure of the RNA and DNA molecules and the activation of enzymes for the metabolism of fats. Our nerves also use calcium for the proper transmission of impulses, and our muscles use calcium to contract and relax.
In addition, calcium lowers cholesterol, by inhibiting plaque formation, and lowers blood pressure, by ensuring the proper functioning of the arterial muscles. This mineral is commonly recommended by natural health care practitioners for osteoporosis, osteoarthritis, cardiovascular disease, PMS, pregnancy, cancer prevention, nervous disorders, muscle cramps and insomnia.
Deficiency of calcium can occur because of insufficient dietary intake or because of increased loss caused by negative conditions within the body. The standard North American diet is high in protein, fat, sugar and phosphorus from the consumption of meats, refined grains, junk foods, salty foods, alcohol, coffee and soft drinks. Not only is this diet low in calcium, it also leads to a disruption of the acid/base balance with a shift towards acidity, and the body is forced to buffer using calcium. The calcium drawn out of the bones to be used as a buffer in the bloodstream is then lost in the urine. This can also be caused by some medications, or when the body is in a state of inflammation, like with inflammatory conditions such as rheumatoid arthritis or lupus. If calcium is deficient, toxic lead is absorbed by the body and deposited in the teeth and bones. The muscles in the body use calcium for contraction and deficiency can result in painful muscle spasms. Similarly, the heart uses calcium in its contractions, so deficiency can lead to arrhythmias. Deficiency of calcium also causes bone and joint diseases such as osteomalacia, osteoporosis and osteo-arthritis. It also leads to poor growth and poor bone density in children (Rickets).
TYPES OF CALCIUM
There are different ways that calcium can be delivered to the body. Many products that contain calcium have less absorbable forms, such as calcium carbonate. Chelated or citrated calcium supplements are easier for the body to use and can be taken with or without food. Chelated simply means that calcium is bonded to a protein molecule, for example aspartate or glycinate, and citrated means that calcium is bonded to a citrate molecule. Both processes enhance calcium's absorption in the intestinal tract. At the same time the greater size of the resulting molecules decreases the amount of calcium per dose unit when compared with simple calcium carbonate. The types of calcium commonly found for supplementation are as follows:
Calcium carbonate is not the best calcium source because it must be taken with food for absorption, and its basic nature may interfere with proper digestion, which requires acidity from stomach acid. Additionally, up to 40% of people over the age of sixty have chronic stomach inflammation that prevents the breakdown of calcium carbonate.
Coral calcium is a naturally occurring calcium found in complex with magnesium oxide in a 4:1 ratio (calcium:magnesium) as well as many other minerals. Two types of coral calcium exist, fossilized and marine. Fossilized coral is farmed after it floats to the top of the ocean while marine grade is live coral that is vacuumed from the ocean floor. There is a debate between the makers of both types as to which is better with no clear winner emerging. One must consider the ecological effect of both processes when purchasing coral calcium. Ensure that your supplement is tested for contaminants since the coral is farmed from the ocean. Even after purification coral calcium contains minute amounts of heavy metals and should not be consumed by pregnant or nursing women.
Microcrystalline Hydroxyapatite Compound (MCHC)
MCHC is sourced from animal bones (usually cow or sheep), and contains a significant amount of calcium, along with other minerals required for proper bone formation. Some practitioners believe that this is an optimal calcium form because it contains all of the other substances that naturally occur in the bone. Like most animal-derived products, it is important to ensure the quality of the supplement and the conditions under which the animals have been raised. To minimize the chance of contamination with heavy metals or disease agents like the prions that cause "Mad Cow disease" (BSE), choose supplements from countries such as New Zealand.
D1-clacium-phosphate is used in some low-end supplements and should be avoided. This form of calcium actually inhibits the absorption of other minerals in a mineral complex and is insoluble. The calcium in antacids, when taken a therapeutic amount, neutralizes stomach acid. They are not recommended as a calcium source because without stomach acid, the calcium cannot be absorbed.
One source of calcium comes from a South American algae named Algas calcareas, which is incorporated into a proprietary bone-building supplement. This particular supplement has been shown to not only slow bone loss, but actually increase bone density over time. For more information on AglaeCal, please click here.
How do I take calcium?
Calcium supplements are best taken in small doses throughout the day because the body can only absorb 500mg at one time, no matter how large an amount each dose contains. However, if you are using calcium for its relaxation properties it is beneficial to take a larger dose before bed, especially when combined with magnesium.
Lysine is an amino acid that is needed for calcium absorption. It can be taken in supplemental form or through the use of foods such as cheese, eggs, fish, lima beans, milk, soy products and brewer's yeast. Calcium absorption is also increased by combination with magnesium and vitamin D. In general, the ratio recommended is 2:1, calcium: Magnesium with an associated dose of Vitamin D (this dose varies widely from 100 – 1000IU).
Calcium and Kidney Stones
Research has proven that calcium supplementation does not cause kidney stones. Instead, it has been found that excessive intake of foods high in oxalic acid (cashews, almonds, beet greens, spinach, cocoa and soybeans) bind with calcium present in the body to create calcium-oxalate kidney stones. These foods also bind calcium in the intestine and prevent its absorption. This can be prevented by decreasing the above-mentioned foods in the diet while supplementing with calcium.
Calcium and Pregnancy
Pregnant women should ensure adequate calcium intake so that the body does not have to pillage its own bones to provide sufficient calcium for the fetus. Calcium also protects against the development of preeclampsia, a hypertensive condition in pregnant women. Coral calcium should be avoided during pregnancy because it may contain trace levels of heavy metals.
Calcium can interfere with the effects of calcium channel blocking heart medications, tetracycline, thyroid hormone, some anticonvulsants and steroids. Calcium is depleted by the use of Phenobarbital and diuretics. Calcium and iron bind together and prevent the absorption of both minerals therefore iron and calcium supplements should be taken different times. Calcium also competes for absorption with zinc, phosphorus and magnesium. Balance your supplemental calcium intake with 50mg of zinc daily. Insufficient vitamin D intake also hinders calcium absorption and should be supplemented in the elderly and by those who live in the northern latitudes.