Magnesium


By Janet Pfeiffer
Magnesium – An Amazing Mineral
Magnesium is commonly known as the anti-stress mineral – though this essential mineral offers so much more.
Many biochemical and physiological processes require magnesium. It is necessary for vitamin C and calcium metabolism. It helps keep teeth healthy, brings relief from indigestion and can aid in fighting depression and migraines. More than 300 enzymes are known to be activated by magnesium. It controls cellular metabolism and maintains electrical potentials of nerve and muscle membranes for the transmission of impulses across junctions. A study published in BMC Bioinformatics found that the human body has 3,751 magnesium binding sites.
Approximately 50 per cent of total body magnesium is found in bone. The other half is found predominantly inside cells of body tissues and organs. Only 1 per cent of magnesium is found in blood, but the body works very hard to keep blood levels of magnesium constant.
Magnesium acts in all the cells of the muscles, heart, liver, and other soft tissues, where it forms part of the protein-making machinery and is necessary for the production and release of energy. Magnesium also helps to relax muscles after contraction and promotes resistance to tooth decay by helping to hold calcium in tooth enamel.
It works together and in balance with calcium in maintaining bone density and in nerves and muscles. For bone integrity, calcium needs to be balanced with magnesium, preferably 2:1. Calcification of soft tissues can occur if there is a calcium/magnesium imbalance. The two minerals also act together in the regulation of blood pressure.
According to recent studies, up to 75% of magnesium is lost during food processing, and 40 – 80 % of Americans fail to meet the RDA levels for daily magnesium intake.
A lack of magnesium is strongly associated with cardiovascular disease. Areas of a country that have hard water – higher in magnesium and calcium – tend to have lower rates of death from cardiovascular disease. A deficiency of magnesium may be related to sudden death from heart failure and to high blood pressure.
Shortage of magnesium can also lead to loss of control over the relaxing and constriction of muscles, as again, calcium and magnesium act in balance.
Bone magnesium seems to be a reservoir to ensure that some will be on hand for vital reactions regardless of recent dietary intake.
Magnesium, like calcium, is a relaxant – yet either one in excess causes a malfunction of the nervous system. Keeping both minerals in balance is important.
Most magnesium is found in the cell where it activates the enzymes necessary for the metabolism of carbohydrates and amino acids. It is involved in insulin secretion and function.
Dietary magnesium is absorbed in the small intestines. Magnesium is excreted through the kidney.
Where has all the magnesium gone?
Food Processing & Cooking – Magnesium may be lost through food processing and refining, and its absorption reduced with a high-fat diet, so it is widely deficient among those with a fast-food diet, and indeed, is deficient in most Western people.
Cooking – Several recent studies have confirmed that cooking diminishes magnesium content in fresh vegetables and legumes. In one study, French beans, broad beans, and peas were boiled for 8-12 minutes. In a second study, spinach and kale were blanched in boiling water for 2-3 minutes. The results: French beans, spinach, and kale lost 20-30% of their magnesium content. Broad beans and peas lost 2-10%.
Processing – Certain processing techniques such as the milling of wheat and the polishing of rice may result in significant losses of magnesium from grains and other foods.
For example, whole wheat typically undergoes refining to remove most of the bran and germ portion of the grain. Only 40 % of the original grain remains after milling. Whole wheat flour contains about six times more magnesium by weight compared to white flour.
Many grain products which have undergone refining, are later “enriched” with the nutrients that were removed (sounds kinda crazy, right?). The FDA has only set standards of enrichment for four nutrients lost during grain processing – vitamins B1, B2, B3 and iron.
Magnesium is not included, so many “white” grains are deficient in this mineral.
So, if you’re looking to enrich your body’s magnesium levels through your diet, consider eating more uncooked greens, and whole grains.
Soil Depletion & Capitalistic Farming Practices – Modern intensive agricultural methods have stripped increasing amounts of nutrients from the soil in which the food we eat grows.
As minerals are removed, stripped away, or no longer available in the soil, the percentage of magnesium present in food has decreased.
The soil from conventional farms is depleted of magnesium because they no longer rotate their crops or let the land rest. Most fertilisers contain nitrogen, phosphorus and potassium – but not magnesium.
A landmark study on the topic by Donald Davis and his team of researchers from the University of Texas (UT) at Austin’s Department of Chemistry and Biochemistry was published in December 2004 in the Journal of the American College of Nutrition. They studied U.S. Department of Agriculture nutritional data from both 1950 and 1999 for 43 different vegetables and fruits, finding “reliable declines” in the amount of protein, calcium, phosphorus, iron, riboflavin (vitamin B2) and vitamin C over the past half century.
The Organic Consumers Association cites several other studies with similar findings: A Kushi Institute analysis of nutrient data from 1975 to 1997 found that average calcium levels in 12 fresh vegetables dropped 27 percent; iron levels 37 percent; vitamin A levels 21 percent, and vitamin C levels 30 percent.
A similar study of British nutrient data from 1930 to 1980, published in the British Food Journal, found that in 20 vegetables the average calcium content had declined 19 percent; iron 22 percent; and potassium 14 percent. Yet another study concluded that we would need to eat eight oranges today to derive the same amount of Vitamin A as our grandparents would have derived from one.
Even organic, non-GMO produce is likely to be lacking in soil-derived nutrients.
Causes of Magnesium Deficiency
Deficiencies can result from:
Malnutrition, including inadequate consumption of fresh vegetables
A diet high in sugar and phytic acid (which hinder absorption of minerals)
The overuse of diuretics and some other medications (such as NSAIDS and antibiotics, which can damage the intestinal lining and flora)
Chronic renal failure
Chronic alcoholism
Uncontrolled diabetes mellitus
Intestinal malabsorption, including conditions such as leaky gut, celiac disease and Crohn’s Disease
Symptoms of Magnesium Deficiency
Muscle tremors or spasms
“Restless leg syndrome” and leg cramps
Chronic weakness and exhaustion
Insomnia or nervousness
Elevated blood pressure and/or pulse
Asthma
Osteoporosis
Headaches and migraines
Heart disease
Irregular or rapid heartbeat
Constipation
Excessive muscle tension
Fits or convulsions
ADD and hyperactivity
Difficulty with mental concentration and memory
Nausea
Apathy, anxiety and depression
Chronic Fatigue Syndrome
Anorexia
Health Benefits of Magnesium Supplements
Digestive Health – Among its many functions in the human body, magnesium helps regulate the transit time of the bowels. In the intestines, it functions as an osmotic laxative – meaning the large intestine uses magnesium to bring water into the bowel, softening the stool, making bowel movements easier.
Magnesium helps keep peristalsis – rhythmic muscle relaxation and contraction – working by proper relaxation of muscles. When magnesium deficiency or calcium-magnesium imbalance is present, poor bowel tone can occur, resulting in constipation. On the other hand, too much magnesium can cause diarrhoea.
In addition, many people find that calcium-magnesium supplements prevent or alleviate the muscle spasms associated with IBS.
Cardiovascular Health – In a study published in the American Journal of Clinical Nutrition, 241,378 participants were given a diet high in magnesium, reducing their risk of a stroke by 8 percent. Another study found that increasing magnesium through diet decreased the risk of a heart attack by 38 percent.
High Blood Pressure/Hypertension – A Harvard study of over 70,000 people found that those with the highest magnesium intake had the healthiest blood pressure numbers. A follow up meta-analysis of available studies showed a dose-dependent reduction of blood pressure with magnesium supplementation. A University of Minnesota study showed that the risk for hypertension was 70% lower in women with adequate – high magnesium levels.
Women’s Health – Magnesium has been shown to be beneficial for women with pre-menstrual cramps or sugar cravings, especially when taken in conjunction with vitamin B6.
Mental Health – Magnesium deficiency is a primary cause of most ADD cases (along with Zinc deficiency) and other types of learning disability and psychological disturbance. Magnesium has been shown to reduce hyperactivity in children who had low magnesium levels.
Twenty schizophrenic patients were evaluated for serum magnesium levels. Of those, 25% were found to be magnesium deficient. Serum magnesium is not a sensitive test of magnesium deficiency, so if red blood cell magnesium had been analysed, the results would likely have been significantly higher.
In drug-treated schizophrenics, magnesium levels have been found to be consistently low. Supplementing with magnesium does not always produce improvement in symptoms. Magnesium injections or use of choline citrate may be necessary at first to “prime the pump”.
Magnesium deficiency can produce depression, agitation, confusion and disorientation.
Vision – Magnesium may improve vision in glaucoma patients.
Fibromyalgia – It is very common for people with fibromyalgia to be deficient in magnesium. Serum magnesium levels are often normal, but if more sophisticated tests are conducted (such as testing red blood cells), magnesium levels are often found to be low.
Most people improve by using oral magnesium supplements, but some require an intravenous injection of 1000mg magnesium sulphate (administered by a physician).
Asthma – Magnesium deficiency is common in people with asthma. Magnesium is a powerful muscle relaxant and can help prevent and reduce the severity of asthma attacks.
Migraines – Numerous studies have documented the relationship between low magnesium levels and migraine headaches. It is estimated that magnesium plays a role in at least half of all people with migraines. When magnesium is supplemented at levels of 600mg daily, the number of migraines significantly decreases (one study showed a decrease of 42%). A recent study used injectable magnesium sulphate with good results.
Diabetes – Magnesium is lost in urine due to the diuretic effect of high blood sugar. Studies suggest that a deficiency in magnesium may worsen the blood sugar control in Type 2 diabetes. Scientists believe that a deficiency of magnesium interrupts insulin secretion in the pancreas and increases insulin resistance in the body’s tissues. In one study, an increase of 100 milligrams a day of magnesium was found to decrease the risk of diabetes by 15 percent.
Osteoporosis — Magnesium is an essential mineral for bone formation and for the utilization of calcium. A study published in Biology Trace Element Research found that supplementing with magnesium “significantly” slowed the development of osteoporosis, after just 30 days.
Chronic Fatigue Syndrome – People with chronic fatigue syndrome (CFS) are often deficient in magnesium. Supplemental magnesium can improve energy levels and emotional states, while decreasing pain. Most people improve with use of oral magnesium supplements, but some require intravenous injections. Physicians can give 1000mg magnesium sulphate by injection.
In one study, magnesium injections improved function in 12 out of 15 people, compared to only 3 receiving the placebo.
Because so many enzymes are dependent on magnesium, a deficiency could affect other nutrients including vitamins B1, B6, E and C and minerals such as zinc, copper and selenium.
Diagnostic Tests for Magnesium Deficiency
Magnesium Serum Test
This is the most commonly performed test when magnesium deficiency is suspected – and it is also the most inaccurate.
Less than 1% of the body’s magnesium is found within the blood plasma and, as mentioned above, the body works hard to maintain homeostasis of this level.
If a Serum Test reveals a low concentration of magnesium, this indicates a severe deficiency. If your plasma is low, you are also deficient in your bones, organs and muscles.
A magnesium serum test is used to measure extracellular magnesium levels. Normal plasma magnesium levels are 1.6 – 2.4 mEq/L.7
Although this is the test most commonly used for diagnostic testing, it does not accurately measure the body’s total magnesium level.
Magnesium RBC Test
The Magnesium RBC Test is a more accurate indication of the body’s magnesium levels.
This test measures the amount of magnesium stored in the red blood cells.
The RBC Test measures intracellular magnesium levels and indicates the quantity of magnesium stored in the red blood cells over the past four months. Results of 6 mg / dl or higher indicates high magnesium reserves in the body.
Magnesium WBC Test
This test is more accurate that the RBC Test.
The WBC test also measures intracellular magnesium levels. But unlike the RBC test, it measures the amount of magnesium currently in the cells – not an average over a period of several months.
This test is not widely available.
Magnesium EXA Test
This is the most accurate diagnostic test to determine the body’s magnesium levels.
The EXA test is performed by scraping the cheek buccal cells to test levels of magnesium stored in the cells, bones and muscles. Like the WBC test, this is considered an intracellular test. The EXA test will account for 99% of the body’s total magnesium levels.
Recommended Best Magnesium Supplements
For people with severe deficiencies, or problems such as chronic constipation, a “loading dose” may be necessary to help correct the issue.
Determining which type of magnesium supplement, and at what dosage level, is best for you may require some trial and error.
Some forms of magnesium are more irritating to the stomach, some are more likely to cause diarrhoea. Some are more easily assimilated than others. You may need to experiment to find the best fit for you.
The suggested daily dose is 400-800mg daily.
Some of my clients have initially required 1000 mg (and in some cases up to 2000mg) per day to treat deficiencies. When their symptoms improve, they are able to lower the dosage accordingly.
If you need large amounts of magnesium, consider taking 1 teaspoon daily of choline citrate to increase absorption.
Magnesium Glycinate – This is my most-recommended form of supplementation – it is considered the most bio-available form of magnesium. The additional glycine in these formulations may help with sleep and lessen anxiety. This form is the least likely to cause diarrhea and stomach upsets.
Magnesium Citrate – This is one of the most popular magnesium supplements. It has average bioavailability. It can cause loose stools in sensitive individuals. Preferably taken with meals – the additional citric acid in the formulation will increase stomach acid and aid assimilation.
Magnesium Gluconate – This is chelated with gluconic acid, which occurs from the fermentation of glucose. It has above average absorption in the body (superior to magnesium citrate). Unlikely to cause stomach irritation or diarrhea. Take in evenings, before sleep.
Magnesium Malate – This form of magnesium is recommended for people suffering severe lethargy or chronic fatigue syndrome (CFS). Magnesium supplementation increases production of
Adenosine triphosphate (ATP). This is a nucleoside triphosphate used in cells as a coenzyme – it is often called the “molecular unit of currency” of intracellular energy transfer. ATP transports chemical energy within cells for metabolism. Malic acid has been demonstrated to increase ATP levels. The additional magic acid in these formulations will increase stomach acid and aid assimilation.
Magnesium Chloride – Recommended for people suffering from digestive issues caused by low stomach acid. Must be taken with food, as the additional chloride will produce more hydrochloric acid in the stomach. Can also be sued topically as a spray for transdermal supplementation.
Magnesium Taurate – Recommended for people with cardiovascular problems. Taurine is an amino acid beneficial for proper heart function – it is often used for atrial fibrillation and similar conditions. Take in evenings, before sleep.
Magnesium Sulphate – This is the form of magnesium used in bath salts such as Epsom salts. Offers relatively good absorption through the skin. Contains sulfur, which can help heal muscle sprains more effectively that most other forms of magnesium, due to its skin permeability. Use in bath as a soaking treatment. Or take orally, before sleep. Also used in intravenous injections, administered by physicians.
Magnesium Arginate – This form is recommended for bodybuilders. Arginine is a vasodilator amino acid, useful for increasing blood flow. best taken with meals throughout the day, as it may produce increased levels of energy.
Magnesium Ascorbate – Contains magnesium and Vitamin C. Can cause stomach irritation and diarrhoea. Take in evenings, before sleep.
Magnesium Lysinate – Contains magnesium and the amino acid lysine. Lysine is an effective anti-viral against the Herpes virus. Take in evenings, before sleep.
Magnesium ZMK – Chelated from components of the Krebs cycle – citrate, fumarate, malate, succinate & alpha-keto-glutarate. Recommended for athletes, aid recovery from workouts. Take in evenings, before sleep.
Magnesium Carbonate – Low grade magnesium supplement – used in antacids (due to its ability to lower stomach acid levels). Very low level of assimilation.
Special Use Magnesium Supplements
Magnesium Orotate – Not widely known, but highly effective for those who workout heavily (or those who have been incapacitated). The additional orotate can assist with muscle regeneration. Some research suggests it is more beneficial to heart health than taurate. Take in evenings, before sleep.
Magnesium L-threonate – May significantly increase magnesium in the brain and spinal column, improving cognitive function – though more research is required. Exhibits superior ability to penetrate the mitochondrial membrane.
Magnesium 2-AEP – Chelated with phosphorylethanolamine, a vital component of the structure and integrity of cell membranes. Research suggests it might be helpful to people suffering MS (multiple sclerosis). Take during the day, with meals.
Magnesium Supplements to Avoid
Magnesium Aspartate – Can provide increased absorption due to the additional aspartic acid. Excessive amounts of aspartic acid can be neurotoxic.
Magnesium Pidolate – Can provide increased absorption due to the additional glutamic acid. Excessive amounts of glutamic acid can be excitotoxic and neurotoxic.
Magnesium Hydroxide – Poor absorption – most is released into the bowels, often causing loose stools.
Magnesium Oxide – Extremely poor absorption.
Magnesium Glycerophosphate – Chelated with phosphorus. Most people already get too much phosphate in their diet. People with kidney problems should avoid this supplement because it is more difficult for them to eliminate excess phosphates.
Magnesium Lactate – Should not be used by people with kidney disease because the additional lactic acid can cause complications for the kidneys.
Magnesium Food Sources
Food | Serving Size | Calories | Magnesium | DRI/DV % |
---|---|---|---|---|
Spinach | 1 cup | 41.4 | 156.6 | 39 |
Swiss Chard | 1 cup | 35.0 | 150.5 | 38 |
Beet Greens | 1 cup | 38.9 | 97.92 | 24 |
Pumpkin Seeds | 0.25 cup | 180.3 | 190.92 | 48 |
Summer Squash | 1 cup | 36.0 | 43.2 | 11 |
Turnip Greens | 1 cup | 28.8 | 31.68 | 8 |
Soybeans | 1 cup | 297.6 | 147.92 | 37 |
Sesame Seeds | 0.25 cup | 206.3 | 126.36 | 32 |
Black Beans | 1 cup | 227.0 | 120.40 | 30 |
Quinoa | 0.75 cup | 222.0 | 118.40 | 30 |
Cashews | 0.25 cup | 221.2 | 116.80 | 29 |
Sunflower Seeds | 0.25 cup | 204.4 | 113.75 | 28 |
Navy Beans | 1 cup | 254.8 | 96.46 | 24 |
Tempeh | 113 grams | 222.3 | 87.32 | 22 |
Buckwheat | 1 cup | 154.6 | 85.68 | 21 |
Pinto Beans | 1 cup | 244.5 | 85.50 | 21 |
Brown Rice | 1 cup | 216.4 | 83.85 | 21 |
Barley | 0.33 cup | 217.1 | 81.57 | 20 |
Lima Beans | 1 cup | 216.2 | 80.84 | 20 |
Millet | 1 cup | 207.1 | 76.56 | 19 |
Kidney Beans | 1 cup | 224.8 | 74.34 | 19 |
Oats | 0.25 cup | 151.7 | 69.03 | 17 |
Tofu | 113 grams | 164.4 | 65.77 | 16 |
Almonds | 0.25 cup | 132.2 | 61.64 | 15 |
Rye | 0.33 cup | 188.5 | 61.35 | 15 |
Wheat | 1 cup | 151.1 | 58.24 | 15 |
Papaya | 1 medium | 118.7 | 57.96 | 14 |
Flaxseeds | 2 tablespoons | 74.8 | 54.88 | 14 |
Green Peas | 1 cup | 115.7 | 53.72 | 13 |
Tuna | 113 grams | 147.4 | 47.63 | 12 |
Scallops | 113 grams | 125.9 | 41.96 | 10 |
Collard Greens | 1 cup | 62.7 | 39.90 | 10 |
Beets | 1 cup | 74.8 | 39.10 | 10 |
Broccoli | 1 cup | 54.6 | 32.76 | 8 |
Brussels Sprouts | 1 cup | 56.2 | 31.20 | 8 |
Raspberries | 1 cup | 64.0 | 27.06 | 7 |
Winter Squash | 1 cup | 75.8 | 26.65 | 7 |
Cabbage | 1 cup | 43.5 | 25.50 | 6 |
Asparagus | 1 cup | 39.6 | 25.20 | 6 |
Kale | 1 cup | 36.4 | 23.40 | 6 |
Green Beans | 1 cup | 43.8 | 22.50 | 6 |
Tomatoes | 1 cup | 32.4 | 19.80 | 5 |
Cantaloupe | 1 cup | 54.4 | 19.20 | 5 |
Strawberries | 1 cup | 46.1 | 18.72 | 5 |
Bok Choy | 1 cup | 20.4 | 18.70 | 5 |
Mustard Greens | 1 cup | 36.4 | 18.20 | 5 |
Cumin | 2 teaspoons | 15.8 | 15.37 | 4 |
Parsley | 0.50 cup | 10.9 | 15.20 | 4 |
Watermelon | 1 cup | 45.6 | 15.20 | 4 |
Mustard Seeds | 2 teaspoons | 20.3 | 14.80 | 4 |
Fennel | 1 cup | 27.0 | 14.79 | 4 |
Leeks | 1 cup | 32.2 | 14.56 | 4 |
Basil | 0.50 cup | 4.9 | 13.57 | 3 |
Cucumber | 1 cup | 15.6 | 13.52 | 3 |
Romaine Lettuce | 2 cups | 16.0 | 13.16 | 3 |
Cauliflower | 1 cup | 28.5 | 11.16 | 3 |
Celery | 1 cup | 16.2 | 11.11 | 3 |
Bell Peppers | 1 cup | 28.5 | 11.04 | 3 |
Cloves | 2 teaspoons | 11.5 | 10.88 | 3 |