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Magnesium Mineral


Approximately 68% of all magnesium in the human body is found complexed with calcium and phosphorus in bone salts. About 26% is found in muscle, with the remainder found in soft tissues and body fluids.

Magnesium is important as a cofactor for enzymes that convert adenosine triphosphate (ATP) to adenosine pyrophosphoric acid (ADP), with the subsequent release of energy. As a constituent of these enzymes, magnesium is essential to reactions involving the synthesis and metabolism of carbohydrates, lipids, proteins, and nucleic acids.

Magnesium acts to relax muscles after calcium stimulates contraction. It is also necessary for the attachment of RNA to the protein-synthesizing ribosomal protein and for the synthesis, degradation, and stability of DNA.

Magnesium has been termed a natural tranquilizer due to its therapeutic effect on the nervous symptoms of magnesium deficiency.

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Method of Action

Magnesium absorption occurs in the upper part of the small intestine and is anywhere from 25% (during high intake) to 70% (at low intake) efficient. Absorption is hindered by the presence of calcium, alcohol, protein, phosphates, and fats. Vitamin D and lactose intake enhance magnesium absorption. Urinary excretion of magnesium is carefully regulated by the kidneys.

Magnesium is essential as a cofactor in the synthesis of RNA from DNA. It is important in the synthesis and degradation of DNA, and also plays a vital role in binding messenger RNA to the 70's subunit of the protein-synthesizing ribosome.

Magnesium is an essential cofactor in the transfer of a high energy phosphate group from phosphoenol pyruvate to adenosine pyrophosphoric acid (ADP), synthesizing adenosine triphosphate (ATP). This is an important energy-producing step in glycolysis.

Magnesium ions are essential for the activity of amino peptidases, which are secreted from the mucosal cells in the intestine to aid in the digestion of proteins.

Magnesium competes with calcium for binding to the troponin molecule found at regular intervals along actin filaments. Troponin undergoes a conformation change and a shift in position upon calcium binding, and hence allows the binding of actin and myosin filaments that occurs prior to muscle contraction. Because magnesium can compete with calcium for troponin binding, it can inhibit this contraction mechanism. A supplement with calcium and magnesium together is not a problem for magnesium absorption if both minerals are chelated and in a plant-base concentrate. Tests have indicated that this type of formula does not inhibit magnesium absorption.

Antimicrobial or anti-infective agents such as neomycin, cycloserin, erythromycin, sulfonamides, tetracycline, penicillin, and para-aminosalicylic acid, tend to inhibit magnesium absorption.

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Properties and Uses

Various gastrointestinal disorders, such as diarrhea and vomiting, may result in magnesium deficiencies. Magnesium supplements can be used in conjunction with rehydration therapy as a preventative measure against neuromuscular irritability (e.g., tremor and spasms) which can result from low serum magnesium.

Magnesium is useful and essential in the treatment of malnutrition in preventing a tetany-like reaction, and in curtailing nervous symptoms brought on by magnesium deficiencies. Burn victims frequently have excessive losses of magnesium and supplementation may be advisable.

Magnesium is useful in protection against heart muscle disease and, in conjunction with vitamin B-6, aids in the removal of kidney stones.

Magnesium is among the trace minerals and vitamins used in the experimental treatment of autistic behavior.

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Consequences of Deficiency

Magnesium deficiency is associated with starvation, persistent vomiting, the trauma of surgery, and inadequate absorption and/or absorption time. Alcohol increases magnesium excretion and can accentuate deficiency. Infants suffering from kwashiorkor may also experience magnesium deficiencies.

Magnesium deficiency can result in a loss of control over the relaxation and contraction of muscles. More severe cases can result in convulsive seizures. Calcification of soft tissues can occur as a result of increased calcium absorption during magnesium deficiencies.

Magnesium deficiency results in decreased resorption of bone as well as increase calcification of soft tissues. This induces hypocalcemia (a condition of low serum calcium level).

Magnesium deficiency inhibits the normal metabolism of potassium and calcium, and in some cases results in anorexia and apathy.

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Toxicity Levels

Magnesium toxicity is very rare except in certain instances where renal failure prevents urinary excretion (i.e., in the situation where magnesium-containing drugs are given to a patient with renal inabilities). Symptoms include central nervous system depression, skeletal muscle paralysis, and in extreme cases, coma and death. Calcium infusion tends to counteract magnesium toxicity.

Healthy kidney function excretes magnesium rapidly and efficiently, with little possibility for toxic buildup. Levels up to 1600 mg daily have proven to be no problem as long as there as a balance of at least 50% calcium intake at the same time.

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Recommended Dietary Allowances

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Food Sources

  • Bone Meal
  • Brown Sugar
  • Cereals
  • Hot Cocoa
  • Beans (dried)
  • Green Peas
  • Eggs
  • Milk
  • Nuts
  • Orange Juice
  • Peanut Butter
  • Potatoes
  • Seafood
  • Soybeans
  • Tomatoes
  • Tuna
  • Whole Wheat

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Summary of Deficiency Symptoms

• Damaged Heart Muscles and Blood Vessels

• Brain Damage

• Susceptibility to Kidney Damage

• Neuromuscular Malfunctions, i.e.,

• High Excitability

• Tremors and Convulsions

• Depression

• Unstable Internal Cell Structure

• Inadequate Stiffening of Cell Membrane Structure

• Inadequate Production of Intracellular Enzymes Including Those Necessary For:

• Energy Production

• DNA Replication

• Inadequate Hormone Production

• Poor Body Growth, Repair, and Cell Maintenance

• Deficiency May Be Caused By:

• Too Many Refined Carbohydrates and Processed Foods

• Gastrointestinal and/or Kidney Disease

• Excessive Diarrhea

• Excessive Alcohol Intake

• Excessive Competitive Mineral Uptake (such as zinc)

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