Magnesium is an essential mineral for health that is required for more than 300 biochemical reactions in the body. It helps maintain normal muscle and nerve function, keeps heart rhythm steady, supports a healthy immune system and keeps bones strong. Magnesium also helps regulate blood sugar levels, promotes normal blood pressure, and is known to be involved in energy metabolism and protein synthesis. Without adequate magnesium, energy production falters and proteins cannot be produced in sufficient quantity for normal growth and development of infants, children, adolescents and pregnant women. In addition, magnesium is important in repair of wear and tear of everyday living, in maintaining resistance to infection, in protecting against cardiovascular, kidney and bone disease and in meeting the excess needs caused by emotional or physical stress.
Even though magnesium should be abundant in numerous foods, the food supply has become increasingly magnesium deficient as the soil and water supply have become depleted of the mineral. A 1936 Senate document (No. 264) from the 74th Congress, second session, first brought to light the subject of mineral deficiencies in the U.S. And in 2006, the World Health Organization (WHO) held a symposium in Baltimore, MD on the subject of “Calcium and Magnesium in Drinking Water,” during which the WHO acknowledged the importance of magnesium in health and the deficiency of this mineral in the world’s water supply.
The 1999-2000 National Health and Nutrition Examination Survey revealed that, “substantial numbers of adults in the United States fail to get recommended amounts of magnesium in their diets. Among adult men and women, the diets of Caucasians have significantly more magnesium than do those of African-Americans. Magnesium intake is lower among older adults in every racial and ethnic group.”
There has been a gradual decline of dietary magnesium in the United States, from a high of 500mg/day at the turn of the century to barely 175–225mg/day today1, and the National Academy of Sciences has determined that most American men obtain about 80 percent of the recommended daily allowance (RDA) and women average only 70 percent.2 “In addition, most magnesium researchers find that the RDA is inadequate to prevent magnesium deficiency, making the above statistics of even more concern,” said Carolyn Dean, MD, ND, medical director of the Nutritional Magnesium Association and author of The Magnesium Miracle.
How Magnesium Works
The health of the digestive system and the kidneys significantly influence magnesium status. Magnesium is absorbed in the intestines and then transported through the blood to cells and tissues. Approximately one-third to one-half of dietary magnesium is absorbed into the body. Gastrointestinal disorders that impair absorption such as Crohn’s disease can limit the body’s ability to absorb magnesium. These disorders can deplete the body’s stores and in extreme cases may result in magnesium deficiency.
Healthy kidneys are able to limit urinary excretion of magnesium to make up for low dietary intake. However, excessive loss of magnesium in urine can be a side effect of some medications and can also occur in cases of poorly controlled diabetes and alcohol abuse. Magnesium is depleted due to stress as part of the fight or flight response.
Magnesium is called up along with adrenaline as part of this response, and when that magnesium-rich blood reaches the kidneys, they’re signaled that there is too much and excrete it through the urine.
Heart Health, Diabetes and Magnesium Deficiency
Dr. C Norman Shealy, MD, PhD, physician, author and founder of the pain and stress management facility, The Shealy Institute location, has expressed that in perhaps no illness is magnesium deficiency more relevant than myocardial infarction or acute heart attack. “On average, patients given intravenous magnesium have a 50 percent greater survival rate than those who do not receive magnesium,” he said.
Another major disease in which magnesium deficiency is rampant is diabetes. According to Shealy, “More critically, magnesium is an important cofactor in production of insulin by the pancreas. Normal total body magnesium is essential for glucose metabolism. Thus, the rampant magnesium deficiency in our society may be a contributing cause of diabetes.”
The following are recent studies showing the positive benefit of magnesium supplementation toward heart health, diabetes and insulin resistance:
• Researchers from the Geriatric Unit of the Department of Internal Medicine and Emergent Pathologies, University of Palermo, Italy, followed up on previous in vivo human studies showing that parenteral or oral magnesium supplementation increased endothelialdependent vasodilation. Their recent study positively concluded that oral magnesium supplementation improved endothelial function in diabetic elderly subjects.3
• One study investigated “whether magnesium supplementation in different disease states, especially insulin resistance and type 2 diabetes mellitus” would be helpful. The authors stated that, “there is good evidence that magnesium could ameliorate insulin resistance and type 2 diabetes mellitus and may even prevent it if intakes are adequate throughout young adulthood.”4
• As the incidence of insulin resistance and metabolic syndrome correlates with the availability of magnesium, researchers’ efforts provided significant evidence that oral magnesium supplementation improves insulin sensitivity even in normomagnesemic, overweight, non-diabetic subjects, emphasizing the need for an early optimization of magnesium status to prevent insulin resistance and subsequently type 2 diabetes.5
Other Areas of Benefit
Beyond aiding with serious conditions like diabetes and cardiovascular health, magnesium supplementation has also been proven useful for a number of other conditions that can benefit young and old, men and women.
PMS and Hot Flashes
• Authors of a study published in Clinical Drug Investigation stated that, “magnesium deficiency has been implicated as a possible contributing factor to some symptoms of premenstrual syndrome (PMS) … Thus it has been suggested that magnesium supplementation may improve certain symptoms in women with PMS.”6
• Researchers from the Department of Internal Medicine Residency Program, Virginia Commonwealth University Health System, Richmond, VA, launched a pilot phase II trial to see if magnesium supplementation would diminish hot flashes in breast cancer patients.7 It was concluded that oral magnesium appeared to have helped more than half of the patients and was well tolerated, and side effects were minimal. A randomized, placebo-controlled trial is planned.
• As magnesium deficiency strongly affects muscle performance and common practices used by athletes to achieve a target weight can lead to magnesium deficiency, a recent study examined magnesium and strength in elite judo athletes according to intracellular water changes (ICW).8 According to researchers, “Higher ICW decreases were associated with higher strength reductions, though our results suggest that an increase in red blood cell magnesium might attenuate those strength reductions in athletes who decrease the ICW compartment. As magnesium losses can be considerable and intake is frequently insufficient, athletes should consider supplementation, especially during periods of weight reduction.”
• A large observational study monitored 810 children from 5 to 12 years of age referred for medical help for attention-deficit/hyperactivity problems, and recommended for consuming polyunsaturated fatty acids (PUFA) in combination with zinc and magnesium by a physician over a period of at least three months. According to researchers, “Our results suggest a beneficial effect of a combination of omega-3 and omega-6 fatty acids as well as magnesium and zinc consumption on attentional, behavioral and emotional problems of children and adolescents.”