The importance of magnesium in the body is too often overlooked in favor of calcium or even iron. Many people may not even know what it is or what it does.
Truth is that this mineral is responsible for over 300 metabolic reactions in the body, including protein, DNA, RNA, and antioxidant synthesis; muscle and nerve function; cell signaling, glucose and blood pressure regulation; and the formation and structure of bones and soft tissue. (1) Yet most people don’t get enough magnesium in their daily diets.
In addition to its role in the synthesis of antioxidants, most notably glutathione (the “master antioxidant”), magnesium binds to heavy metals in the blood (e.g., cadmium, chromium, nickel, zinc, and others), assisting in their elimination from the body. (2, 3) It also has the ability to prevent stroke.
Magnesium from food is absorbed in the small intestine and is distributed throughout the body in the blood. It is part of bones and soft tissue. The kidneys maintain a proper magnesium level in the blood and if there’s too much, it gets flushed out as waste. (4)
The Dangers of Magnesium Deficiency
In 2009, the World Health Organization reported that 75% of Americans were magnesium deficient. A recently published meta-analysis of forty separate studies from nine countries regarding the effects of magnesium on human health involved over one million participants over a period of four to thirty years and found some interesting results.
Here’s what they found:
- Many people have low serum (blood) magnesium levels (2.5-15% of subjects in included studies).
- Increasing daily magnesium by 100mg a day didn’t affect the incidence of cardiovascular disease or coronary heart disease.
- Increasing daily magnesium intake by 100mg a day significantly reduced the risk of stroke, heart failure, type 2 diabetes, and all-cause mortality.
“…many adults fail to meet the recommended daily intake of magnesium, despite the fact that epidemiology studies indicate that low levels of serum magnesium can increase the risk of a wide range of diseases, including chronic obstructive pulmonary disease, metabolic syndrome, type 2 diabetes (T2D), Alzheimer’s disease, and cardiovascular disease (CVD)…However, no clear association was found between magnesium intake and the risk of coronary heart disease or total cardiovascular disease, which may have been due – at least in part – to the relatively limited number of studies included in our analysis.” (5)
The current recommended dietary amount for magnesium is 400-420mg for men over 19 years and 310-320 for women (add 40mg if pregnant for healthy fetal development). (6)
Importance of Magnesium
Dr. Mildred Seelig was a world-renowned magnesium scholar. She published studies and books about magnesium and its role in human physiology and the consequences of chronic deficiency.
In her book Magnesium Deficiency in the Pathogenesis of Disease, she cites inadequate magnesium as a significant factor in:
- Ischemic heart disease
- Sudden infant death
- Infantile myocardial infarction (heart attack) and arteriosclerosis
- Bone disease
- Kidney disease and kidney stones
- Imbalance among magnesium, vitamin D, and phosphorus—too much calcium and/or phosphorus increases the body’s need for magnesium and exacerbates magnesium deficiency symptoms (7)
- Fetal tissue development, eclampsia, and toxemia during pregnancy (8)
In a separate study, Dr. Seelig described the link between vitamin D, magnesium, calcium, and phosphorus: these nutrients must be in balance in order for the body to properly process each. (9) There is no hard answer on what the ratio should be for a particular person because the variables are too great. (10)
It is therefore critical to maintain a healthy balanced diet, get your dose of sunshine, and cut out soft drinks (they are ridiculously high in phosphorus, which leads to magnesium depletion) in order to use each of these nutrients effectively. (11)
Additionally, chronic magnesium deficiency can cause:
- Arrhythmia (12)
- Memory loss
- Migraine headaches
- Restless leg syndrome
Magnesium Deficiency and Heart Disease
“Mid-1950s, USA: Something in our lifestyle was allowing many otherwise healthy people to drop dead from heart attacks. The search was on for the cause. With no pathogen and no toxin, researchers began to look for things that ‘correlated’ with heart attacks or strokes. Factors associated with an elevated risk of heart disease became the way to study this increasing problem. High blood pressure, smoking, obesity and high serum cholesterol came to be the best known of a growing list of cardiovascular risk factors—things to avoid or clinical measurements to correct.”
“However, populations from all over the world showed high rates of sudden cardiac death in areas with low soil and/or water magnesium levels; and animal research as early as 1936 implicated low nutritional magnesium in atherosclerosis—the hardening of arteries. By 1957 low magnesium was shown to be, strongly, convincingly, a cause of atherogenesis and the calcification of soft tissues. But this research was widely and immediately ignored as cholesterol and the high saturated-fat diet became the culprits to fight.” (13)
This excerpt is from studies by Andrea Rosanoff, Ph.D., a colleague and collaborator with Dr. Seelig who continues Seelig’s work. While it is certainly true that hypertension, obesity, smoking, and chronically high LDL cholesterol contribute to cardiovascular disease, they aren’t the only factors—they have become the most conspicuous markers.
Doctors often don’t test for blood or urine magnesium when treating or aiming to prevent heart disease.
How Did This Happen?
Somewhere along the line, calcium and vitamin D became trendy nutrients and people were told they needed more of both. Milk and many packaged foods have been fortified with them for years (as synthetic supplements).
Without balance among these, magnesium, and phosphorus, body chemistry is thrown out of whack and you end up with inadequate magnesium to offset the larger amounts of calcium and vitamin D. From Dr. Rosanoff: “high cellular Ca:Mg [calcium to magnesium] ratios manifest in tissues as the ‘fight or flight’ response, bringing on clinical symptoms of CVD.”
Rosanoff explains that processed foods contain few ingredients that contain naturally-occurring magnesium. Furthermore, commercial wheat, fruit, vegetables, and other food crops have been so hybridized, chemicalized, and genetically modified that their natural magnesium content has noticeably decreased in the last 60 years. (Yet another reason to eat organic!)
“As the modern processed-food diet and the stressful high-Mg-requiring lifestyle that goes with it expand throughout the world, more and more of the growing human population will experience the marginal Mg status our society has been living with for decades, and we can expect (and we now see) increasing levels of CVD as a result.” (Ibid.)
Some health conditions can contribute to magnesium depletion, such as:
- Gastrointestinal disorders: chronic diarrhea, Crohn’s disease, intestinal inflammation due to surgery or radiation therapy
- Kidney disorders: diabetes, taking diuretics, other medications
- Age: the older we get, the more difficult it becomes for the intestines to absorb magnesium from foods.
15 Magnesium-rich Foods to Prevent Stroke, Heart Failure, and Diabetes
This is by no means an exhaustive list but a guide for the most common foods with a high magnesium content. Leafy greens, nuts, legumes, whole grains, and seeds of all kinds are high in magnesium.
- Beet greens
- Raw cacao
- Collard greens
- Cruciferous vegetables, including broccoli, Brussels sprouts, bok choy, and kale
- Fatty fish (e.g., wild-caught salmon, mackerel)
- Fruits and berries, including bananas, and figs
- Herbs, including chives, parsley, fennel, and basil
- Nuts, seeds, and legumes, including almonds, cashews, pine, and Brazil nuts; sunflower and pumpkin seeds, lentils, and Lima beans
- Romaine lettuce
- Swiss chard
- Spices, including coriander, cumin, mustard seed, and clove
- Turnip greens
When it comes down to the nuts and bolts of life, Magnesium is a catalyst we couldn’t live without.
Magnesium passes through cell membranes, transporting other minerals (such as potassium) from cell to cell throughout the body. Communication between cells requires protein synthesis that is catalyzed by magnesium. The processes that result from the break-down of proteins affect hormone secretion and gland function.
Additionally, magnesium and calcium that float around outside of cells carry them to different parts of the body, with implications for immune system function. (14)
Magnesium’s Role in the Prevention of Stroke and Diabetes
Magnesium is a potent vasodilator, meaning it opens up blood vessels, thereby decreasing blood pressure. Ischemic stroke (the most common) occurs when there is a blockage or blood clot in a blood vessel that cuts off blood flow to the brain. Dilation of blood vessels to prevent blockage is therefore highly preventative.
Magnesium deficiency commonly affects people with diabetes, both types 1 and 2; almost half of people with type 2 diabetes are lacking in this mineral.
The mechanism that causes this effect may be increased loss of magnesium via urination as the body tries to rid itself of excess sugar. Inadequate magnesium has been shown to increase insulin resistance, which makes it harder for the body to regulate blood sugar.
Other Sources of Magnesium
Food isn’t the only source of magnesium: Epsom salts and seawater are also rich in this important mineral and your skin will absorb it. Too much magnesium is almost impossible if it comes from food or through the skin.
Magnesium supplements are available but as with any supplement, if it’s not derived from a food source, it’s synthetic and not readily used by the body. It is possible (and toxic) to get too much magnesium from supplements.
Adverse effects of excess magnesium supplementation include:
- Diarrhea (magnesium is a laxative, hence milk of magnesia)
- Muscle weakness
- Kidney dysfunction
- Difficulty breathing
- Heart attack (in extreme cases)
The Food and Nutrition Board of the Institute of Medicine advises against magnesium supplementation if you have any problems with your kidneys. The upper limit of daily magnesium intake via supplement is 350mg for adults. Less than that doesn’t cause trouble in most people. (15)
Drug Interactions with Magnesium
Magnesium supplements adversely impact actions of the following medications. It’s always best to inform your healthcare provider if you a) want to begin supplementation or b) are already taking supplements of any kind.
- Anti-malarial drugs
- Bisphosphonates for osteoporosis
- Digoxin (heart medication)
- Nitrofurantoin (antibiotic)
- Penicillamine (antibiotic)
- Proton-pump inhibitors for stomach acid
- Quinolone (antibiotic)
- Tetracycline (antibiotic)
Food is our fuel, our sustenance, and our medicine. Anything you buy in a package or grow synthetic chemicals will get to you eventually.
Real organic food works with your body to nourish and maintain balance. Swallowing a pill may seem more attractive than eating a salad but there really is no substitute when it comes to promoting health.