Magnesium, Health, and Disease Prevention
by Chris D. Meletis, N.D.
Magnesium is one of the major mineral nutrients in the human body. Containing approximately 20 to 28 grams of magnesium; 60 percent of which is found in the bones and teeth, the remaining 40 percent is found in muscle. Magnesium is the second-most positively charged ion found within the cells of the body, signifying its importance in the multitudes of physiologic cellular functions. One of the most important metabolic processes, the synthesis and consumption of energy (or ATP), is directly linked to magnesium. This magnesiumlinked ATP process activates approximately 300 different enzymes, which are involved in diverse functions, such as DNA and RNA synthesis, intracellular mineral transport, nerve impulse generation, muscle contraction, blood vessel tone, and the regeneration of ATP.
The adult Recommended Dietary Allowance (RDA) for magnesium is 350 mg per day for men and 280 mg for women. The typical American diet provides approximately 120 mg per 1,000 calories, meaning that a person that consumes fewer than 1,500 calories is likely to be deficient in magnesium. The absorption rate of magnesium ranges from 24 to nearly 85 percent; magnesium derived from metallic sources is less absorbable, while that from plant sources is more easily absorbed. Factors that deplete or limit the uptake or absorption of magnesium include excess phosphate consumption (soft drinks) and alcoholic beverages, high-stress lifestyles, some diuretics, digitalis, strenuous exercise (considerable amounts of magnesium is lost in sweat), pregnant and lactating women, and individuals with diabetes, severe diarrhea, or kidney disease. The early signs of magnesium deficiency include vague symptoms, such as loss of appetite, stomach ache, and diarrhea. Longer-term deficiency symptoms may manifest as confusion, apathy, depression, irritability, arrhythmias, weakness, poor coordination, nausea, vomiting, electromyographic changes, muscle and nerve irritability, and tremors.
Magnesium has many novel uses for common health conditions. As an antacid, magnesium salts react with gastric acid to form magnesium chloride, which neutralizes hydrochloric acid. As a laxative, magnesium draws water into the intestines and colon, as well as triggering the release of hormones stimulating and enhancing digestion. This mineral is also known to inhibit pre-term labor contractions.
MAGNESIUM AND BLOOD PRESSURE
Magnesium has an important role in reducing blood pressure. A deficiency has been found to allow for increased concentrations of sodium and potassium in cells, resulting in the constriction of blood vessels. By replacing magnesium, it relaxes the blood vessels, thus reduces blood pressure. Diets that contain plenty of fruits and vegetables—both great sources of potassium and magnesium—are consistently associated with lower blood pressure. The effect of various nutritional factors on high blood pressure was examined in over 30,000 U.S. male health professionals. After four years of followup, it was found that greater magnesium intake was associated with lower hypertension risk. The Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure recommends maintaining adequate magnesium levels for preventing and managing high blood pressure.
MAGNESIUM AND HEART DISEASE
Magnesium may play a role in reducing coronary vascular constriction, increasing coronary artery blood flow, and preventing arrhythmias. Further, inadequate magnesium levels and absorption are associated with the development of hypertension, cardiomyopathy, atherosclerosis, and stroke. Evidence exists that low stores of magnesium actually increases the risk of a person having arrhythmias, which can increase the risk of cardiovascular complications. Surveys of the general population have associated higher blood levels of magnesium with lower risk of coronary heart disease. Dietary surveys also suggest that a higher magnesium intake is associated with a lower risk of stroke.
MAGNESIUM AND OSTEOPOROSIS
Magnesium deficiency may be a risk factor for postmenopausal osteoporosis, due to how a deficiency may negatively alter calcium metabolism and the hormone that regulates bone-calcium stores. Several studies suggest that magnesium supplementation may improve bone mineral density, as well as to associate low intake and impaired absorption of magnesium with developing osteoporosis.
MAGNESIUM AND DIABETES
Magnesium plays an important role in carbohydrate metabolism, influencing the release and activity of insulin, the main hormone that exerts control of blood glucose levels. Elevated blood glucose levels can increase the loss of magnesium in the urine, leading to increased deficiency.
MAGNESIUM AND ASTHMA
Magnesium plays a dynamic role in lung structure and function. Magnesium acts to block the function of calcium, which in the lungs causes bronchial smooth-muscle contraction. The possibility exists that magnesium deficiency may contribute to lung complications. It is interesting to note that though the average calcium consumption in the U.S. has increased in the past few years, there has been little change in magnesium intake, causing an imbalance in the calcium:magnesium ratio. This deficiency also affects the activity of specific white blood cells during an asthma attack, worsening the condition. Researchers theorize that low magnesium content of white blood cells has an important effect on the development of asthma over time.
It is further hypothesized that a diet high in magnesium is directly related to healthy lung function and a reduced risk of airway hyper-reactivity and wheezing. Low magnesium intake may therefore be involved in occurrences of asthma.
The beneficial health effects of magnesium and its diseaseprevention qualities emphasize the importance of this commonly overlooked mineral. As the fields of nutrition and medicine continue to reveal the benefits of magnesium, it becomes more apparent that its proper supplementation is vital to maintaining our health. As with the use of all supplements, seek the advice of a qualified, nutritionally oriented physician.