Magnesium Supplement Uses, Benefits, Dosages, Side Effects & Interactions
Magnesium (Mg) is an essential element that is needed for hundreds of important biochemical reactions inside the human body.
It is essential for the synthesis of enzymes that regulate a diverse range of bodily functions and processes including blood pressure, nerve function, blood glucose regulation, and protein synthesis. 
Our bodies need magnesium to produce cellular energy, synthesize RNA and DNA, develop and maintain strong bones, and to produce various essential antioxidants including glutathione and superoxide dismutase (SOD).
Magnesium also helps to transport potassium and calcium ions through cell membranes, improving cellular signaling. It is necessary for muscle contraction, cardiac function, and neuronal impulse conduction inside the brain.
This article will give an overview of how magnesium works in the body, common uses, health benefits, and symptoms of deficiency.
Supplement and food sources, common dosages, safety and side effects, and potential interactions with drugs and other supplements will also be discussed.
MagnesiumEssential Mineral Memory Mood Sleep Quality How It Works:Supports learning and memoryReduces stress & anxiety responseImproves sleep quality & Restless Leg SyndromeDosage:Between 200 – 500 mg per daySafety:Rated Likely Safe
Magnesium Overview and how it Works in the Body
Magnesium is a white/silver earth series metal with atomic number 12. The chemical symbol for magnesium is Mg. 
Magnesium is a highly abundant element, and is the ninth most abundant in the universe.  It is the eighth most common element in the Earth’s crust.
Most of this element is found not in the Earth’s crust, but beneath it in the mantle. Inside the Earth magnesium is the fourth most abundant element after oxygen, silicon, and iron. This element comprises about 13% of Earth mass. 
Magnesium is the 11th most abundant element found in the human body. About half of the body’s Mg is stored in the bones. An adult male weighing 160 pounds will have between 21 and 28 grams of this element in his body. 
Almost all of the remainder is found inside cells. The average healthy human has between 1.7 and 2.5 mg/dL Mg in their serum (blood). 
The body uses magnesium mainly as an electrolyte to maintain fluid homeostasis inside cells.
It is also used as a cofactor in more than 300 enzyme systems required to facilitate processes including ATP production, creatine kinase activation, glycolysis (breakdown of glucose which releases energy), and many others.
Low levels of this mineral can disrupt sleep, blood pressure, and heart rate. Being deficient in this essential element can also cause neuronal over-excitation and lower the amount of glucose in the blood.
Common Magnesium Uses
The Natural Medicines Comprehensive Database (NMCD) reports that people take magnesium supplements for dozens of uses including:
Allergic rhinitis (seasonal allergies, hay fever)
Attention-deficit hyperactivity disorder (ADHD)
Chronic fatigue syndrome (CFS)
Hyperlipidemia (high blood lipid levels)
Increase energy and endurance
Laxative for constipation
Pregnancy-related or nocturnal leg cramps
Premenstrual syndrome (PMS)
Restless leg syndrome (RLS) 
The NMCD rates magnesium as Effective for constipation, dyspepsia (heartburn), hypomagnesemia (magnesium deficiency), preeclampsia (high blood pressure and blood protein levels during pregnancy), and eclampsia (seizures resulting from preeclampsia).
It is rated as Likely Effective for Torsades de pointes, a specific type of ventricular tachycardia (abnormally fast heart rate). 
The NMCD also rates magnesium as Possibly Effective for:
Cancer-related neuropathic pain (nerve pain)
Chronic obstructive pulmonary disease (COPD)
Hypercholesterolemia (high blood cholesterol levels)
Mitral valve prolapse
Vasospastic angina (type of chest pain) 
Some promising results have been seen in research using magnesium for ADHD, anxiety, bipolar disorder, cardiovascular disease, migraines, multiple sclerosis, and RLS. More research is still needed to determine the therapeutic efficacy of this supplement for these and other conditions.
Certain high-dose formulations of magnesium are regulated as prescription medications in parts of the world and can only be obtained with a prescription from your doctor.
Magnesium is also available as a dietary supplement. Products sold as nutritional supplements are not approved by the US Food and Drug Administration as drugs to prevent or treat any medical conditions.
It is always best to talk to a medical professional who understands your health history when you are considering using a new supplement. This nutrient affects numerous biological pathways and can induce various physiological effects.
Seek medical advice before increasing your magnesium intake, either by eating more food sources or by taking a supplement.
Sleep and Insomnia
While the mechanisms are still not entirely understood, it is believed that magnesium plays a role in the regulation of sleep.
Using a supplement that contains this mineral may induce some sedative-like actions in humans, possibly through its role as a natural N-methyl-D-aspartic acid (NDMA) antagonist and GABA agonist. 
Intentional sleep deprivation (only sleeping 80% of normal levels) over 4 weeks is associated with a 3.5% reduction in erythrocytic (red blood cell) Mg concentrations. 
It has also been observed that low levels of this mineral in the diet are associated with sleep issues such as insomnia.
The role of supplemental magnesium for sleep disorders is currently being studied.
In one study involving 12 healthy elderly participants, 10- 20 mmol/day doses of effervescent Mg for 20 days improved certain sleep factors. Slow-wave sleep periods increased by 63.3% and sleeping cortisol levels were significantly reduced. 
In other research, supplementation with 320 mg magnesium citrate daily over 49 days showed improvements in inflammation parameters as well as sleep quality. 
Researchers are still not sure if low Mg status is a cause of or an effect of poor sleep quality. More research is needed to determine the therapeutic efficacy of supplementation on sleep disorders and insomnia.
If you are interested in taking this supplement to improve your sleep patterns then speak with your doctor for more information.
Diabetes and Blood Sugar Regulation
Magnesium status can affect some parameters of diabetes and blood sugar regulation. This nutrient is known to be important for sugar/glucose/carbohydrate metabolism.
Multiple prospective cohort studies have validated an inverse relationship between the risk of diabetes mellitus and magnesium intake. 
According to the National Institutes of Health (NIH), “Diets with higher amounts of magnesium are associated with a significantly lower risk of diabetes, possibly because of the important role of magnesium in glucose metabolism.” 
Low magnesium status is also associated with decreased insulin secretion, decreased pancreatic function, and decreased sensitivity to insulin. Some clinical studies have reported improvements to insulin sensitivity with daily doses of supplemental Mg between 300 and 365 mg/day. 
In one clinical trial, patients with poorly controlled diabetes were admnistered either a placebo or a magnesium oxide supplement of either 500 mg or 1000 mg per day (which provided 300 or 600 mg elemental Mg respectively).
After 30 days of treatment, patients in the higher dose treatment group had increased blood levels of this mineral and improved glycemic control. 
In another study, for 16 weeks patients with type 2 diabetes and hypomagnesemia (low Mg levels) were given either a placebo or a liquid supplement of magnesium chloride that provided 300 mg/day elemental Mg.
Compared to the placebo group, the treatment group showed normalized Mg levels and significant reductions in fasting glucose levels. 
In another placebo-controlled study, participants were given magnesium aspartate providing 369 mg of elemental Mg per day for three months. The supplement had no significant effect on glycemic control in type 2 diabetics who were also taking insulin. 
Researchers are still not sure how this mineral affects insulin sensitivity, glucose uptake, insulin secretion, or blood glucose homeostasis. More research is needed to understand the effects of supplements in diabetics who are not deficient in magnesium.
If you are interested in taking magnesium, then speak with your doctor or endocrinologist for more information.
Magnesium is important for maintaining a healthy cardiovascular system. Being deficient in this nutrient is associated with an increased risk of cardiovascular disease in general and hypertension (high blood pressure). 
Research has shown that in men who are deficient, supplementing with magnesium may reduce the risk of coronary heart disease. 
It is needed in the body to balance the adverse effects of high calcium levels which can play a role in various aspects of heart disease.
According to the NMCD, “In cell membranes, a decreased concentration of magnesium and increased Ca to Mg ratio has also been associated with hypertension.” 
Additionally, in research studies it has been seen that Mg may help prevent or reverse arterial plaque formation and arterial calcification, causal factors of cardiovascular disease. 
In emergency situations, this supplement is administered post-heart attack to decrease the risk of mortality. It is also used to treat congestive heart failure and to decrease abnormal heart rhythm (arrhythmia) incidents. 
There is some evidence of improvements to blood lipid profiles with daily supplemental magnesium doses of 365 milligrams. However, 450 mg/day Mg doses for 4 months failed to reduce triglyceride counts in adults with hypertension. 
The cardiovascular benefits of magnesium supplementation are not yet well defined.
In research studies, benefits seem to be more prevalent in people with Mg deficiency. Those with adequate magnesium levels seem to benefit less from administration.
If you have any type of cardiovascular condition and are interested in learning more about magnesium supplementation it is recommended that you speak with your doctor.
Obesity and Weight Loss
Magnesium deficiency is a common biomarker associated with obesity and overweightness. However, it is not likely to be a causal factor of obesity. 
The NMCD reports that research suggests a link between low Mg levels and obesity-related health conditions such as insulin resistance, low-grade whole-body inflammation, and certain cardiovascular risk factors. 
However, there is not a direct link with obesity and no research shows an explicit causal relationship between supplementing with Mg and weight loss.
Some preliminary evidence suggests that magnesium may be able to inhibit the absorption of fats from the diet. 
Magnesium may indirectly help to control some of the factors that can eventually lead to weight gain and obesity by supporting cardiovascular function and helping to improve blood glucose management. 
More clinical research is needed to determine how magnesium affects obesity and weight gain, possibly by enhancing glucose uptake into cells, increasing energy, improving cardiac performance, decreasing insulin resistance, and other mechanisms yet to be explored.
Bone Health and Osteoporosis
Magnesium is important for developing and maintaining healthy bones and teeth.
It enhances bone crystal formation and increases bone density by improving the assimilation of calcium into bone tissue. This nutrient also helps to activate vitamin D inside the kidneys which further supports bone health. 
Some research has shown that supplementing with Mg is beneficial for postmenopausal women with osteoporosis. 
However, data is limited and more studies are needed to determine how supplemental magnesium affects dental and/or skeletal health in humans.
If you have been diagnosed with any teeth, bone, or joint conditions and are considering using a Mg supplement, then you should ask you osteopath or primary caregiver about it first.
Magnesium deficiency is very common, even in developed countries. According to Dr. Joseph Mercola, up to 80% of people in the US may be deficient in this nutrient. 
He states that more than 20 health conditions may be triggered, or directly caused, by deficiency including:
Gynecologic/obstetric disorders like preeclampsia, PMS and infertility
High blood pressure (hypertension)
Low blood glucose (hypoglycemia)
Musculoskeletal disorders like fibromyalgia, chronic back pain and muscular cramps
Nervousness, anxiousness and panic attacks 
According to Dr. Mercola, being chronically deficient can also cause asthma, bowel disease, depression, chronic fatigue, type 2 diabetes and/or insomnia. 
Over time, not getting enough of this essential mineral in the diet can increase the risks of developing various health disorders.
It may trigger high blood pressure, cardiovascular disease, kidney disease, liver disease, migraine headache, tooth decay, and osteoporosis, as well as various other conditions. 
Some of the early warning signs of deficiency include poor appetite, nausea, headache, fatigue and weakness.
If the deficiency is not rectified, then more serious symptoms may develop including heart rate alterations, personality changes, tingling/numbness, muscle cramps, involuntary muscle contractions, seizures, and/or heart spasms. 
If left unresolved, magnesium deficiency may become severe. This is called chronic hypomagnesemia and is known to disrupt the homeostatic balance of vitamin D, calcium, and other important nutrients in the body. 
Hypomagnesemia is most likely in the elderly, chronic alcoholics, and in those with kidney and/or gastrointestinal disorders.
Magnesium Food Sources
In general, the best magnesium-rich foods are unprocessed green leafy vegetables, nuts, seeds, sprouts, beans and legumes. It is recommended to limit processed foods and common meat products in order to have optimal levels of this nutrient in your diet.
Some of the best food sources include:
Dry-roasted sunflower seeds: 128 mg per ¼ cup serving
Dry-roasted almonds: 105 mg per ¼ cup serving
Roasted sesame seeds: 101 mg per 1-ounce serving
Boiled spinach: 78 mg per 1 cup serving
Black beans: 60 mg per ½ cup serving
Broccoli: 51 mg per 1-cup serving
Shelled, cooked edamame: 50 mg per ½ cup serving 
Other magnesium-rich foods include dairy products, some meats, oats, seaweed, peanut butter, shrimp, brown rice, kidney beans, and bananas.
Note that the nutrient content of any plant food will be determined by the nutrient profile of the soil it was grown in. Magnesium-poor soil cannot grow Mg-rich produce. Be mindful about the source of your produce. Search for non-GMO, organic foods when possible.
Mass farming operations, Mg-chelating herbicides like glyphosate, the processing of food, and cooking all affect the amount of this and other nutrients we get from our diets.
There are also certain foods that make your body less able to assimilate and utilize magnesium efficiently. For instance, drinking too much alcohol can inhibit vitamin D absorption, which can subsequently affect Mg uptake into cells.
Another important factor to consider is sugar intake. It requires 54 molecules of Mg to process 1 molecule of sugar. People who may be magnesium deficient can further deplete their status by overconsumption of sugar-rich foods and beverages. 
Use of certain pharmaceuticals, gastrointestinal health problems, poor diet, dehydration, exercise, and other factors can also affect Mg status.
It is important to balance your magnesium intake with proper amounts of calcium, vitamin D, and vitamin K. 
Failure to balance mineral intake can result in numerous adverse health conditions. It is best to discuss the how to balance the nutrients in your diet with a doctor or dietician.
Forms of Magnesium Supplements
The NMCD states that there are over 20,000 different dietary supplements available that contain magnesium as a single ingredient or in combination with other minerals and/or vitamins. Typical doses for supplements range between 200 and 500 mg daily.
Some of the most common forms of this mineral found in supplements include:
Magnesium Citrate, water soluble, 25-30% bioavailability, low cost, most common form
Magnesium L-Threonate, used largely for increasing brain Mg and improving learning
Magnesium Diglycinate, absorbed uniquely in gut, relatively low bioavailability
Magnesium Dihydroxide (Milk of Magnesia), used as laxative and antacid
Magnesium Aspartate, bound to aspartate, up to 40% bioavailability
Magnesium Oxalate, low bioavailability, used mainly as a laxative
Magnesium Orotate, Mg bound to orotic acid, good safety profile
The NMCD states that bioavailability varies by supplement formulation. Magnesium glycinate, taurate, threonate, and aspartate have the highest bioavailability.
Magnesium oxide and sulphate have only about 4% bioavailability when used as oral supplements. This means that only a small amount of the active dosage you consume will be absorbed and utilized by the body.
Magnesium oxide and chloride are associated with increased incidences of bloating and diarrhea when compared to other forms of Mg supplements. This is said to be due to lower rates of absorption inside the gastrointestinal tract.
Magnesium gluconate and diglycinate are used commonly for superloading Mg, but this should be done only under medical supervision.
Supplements should be taken with food and according to label instructions.
According to some experts, magnesium citrate is one of the best all-around choices. You should ask a nutritionist or your doctor about which form of this supplement is best for your needs.
Magnesium Dosage Guidelines
The NMCD reports that the recommended dietary allowances (RDA) for elemental magnesium are as follows:
1-3 years old: 80 mg/day
4-8 years old: 130 mg/day
9-13 years old: 240 mg/day
14-18 years old: 410 mg/day males, 360 mg/day females
19-30 years old: 420 mg/day males, 310 mg/day females
Adults 31 and older: 420 mg/day males, 320 mg/day females 
Pregnant women under 18 are advised to take 400 mg/day, 350 mg/day if you are between 19 and 30 years old, and 360 mg/day if you are over 31 years old.
Breastfeeding women under 18 are recommended to consume 360 mg/day, 310 mg/day if you are between 19 and 30, and 320 mg/day if you are over 31 years old.
The Food and Nutrition Board of the Institute of Medicine set an upper tolerable level (UL) for magnesium supplements of 350 mg/day for people from 9 years old and older.
The LPI reports that “this UL represents the highest level of daily supplemental magnesium intake likely to pose no risk of diarrhea or gastrointestinal disturbance in almost all individuals.” 
Getting too much of this mineral from foods and/or supplements can cause adverse health effects, particularly in those with kidney dysfunction/disease. Speak with your doctor to determine the best dosage for your needs.
Magnesium Supplement Stacks
Magnesium is sometimes taken in combination (stacked) with other nutrients to promote synergistic health benefits.
Some of the most common supplements stacked with Mg include fish oil, vitamin C, and L-theanine.
People take these stacks for various conditions including anxiety, insomnia, diabetes, cardiovascular disease, fatigue, and more.
According to the NMCD, caution should be exercised if supplementing magnesium with:
Boron, because it can reduce urinary excretion of Mg, possibly elevating serum levels
Calcium, because it decreases Mg absorption at supratherapeutic doses (>2600 mg/day)
High amounts of fiber in the diet, because it may decrease Mg utilization
Low protein in the diet, because it can decrease Mg absorption
Zinc, because it may decrease Mg at high doses (>140 mg/day)
Discuss supplement stacks with a health professional who understands your health history before beginning to combine ingredients together.
Side Effects and Interactions
The NMCD rates magnesium as Likely Safe when used orally and appropriately in doses under the daily UL of 350 mg.
This supplement is rated as Possibly Unsafe in doses above the UL. Taking excessive dosages can cause diarrhea, loose stools and other gastrointestinal side effects. 
Magnesium is generally well tolerated when taken in appropriate dosages. However, it may also cause cause nausea, vomiting, gastrointestinal irritation, and/or diarrhea when used at recommended dosages. 
Very rarely, large dosages taken orally may cause low blood pressure (hypotension), confusion, thirst, weakness in muscles, cardiac arrhythmia, drowsiness, and/or coma. 
Dangerously high doses might also cause loss of CNS (central nervous system) control.
Individuals with renal (kidney) insufficiency should not use magnesium supplements unless instructed to do so and monitored by their physicians. 
Consult with a doctor before taking this supplement if you use antacids, bisphosphonates, calcium channel blockers, digoxin, and/or gabapentin. 
Be careful using supplements with antiplatelet/anticoagulant drugs and/or herbal supplements, as this combination may increase the risk of bleeding.
In in-vitro (cultured cell) studies, magnesium sulfate has been shown to slow down the aggregation of blood platelets, even at low concentrations.
Preliminary data suggests that Mg can significantly reduce the activities of platelets, increasing bleeding times by as much as 48%. However, other data suggests no platelet inhibition activities. 
Exercise caution if taking magnesium with potassium-sparing diuretics, quinolone antibiotics, tetracycline antibiotics, aminoglycoside antibiotics, skeletal muscle relaxants, and/or sulfonylureas. 
Some herbal supplements that can interact with magnesium supplements include angelica, ginseng, turmeric, ginger, dashen, clove, and garlic. 
Other interactions with medications and supplements can occur. It is recommended that you speak with your doctor before beginning to take a magnesium supplement.
Top Rated Supplements
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Dr. Joseph Mercola Magnesium: An Invisible Deficiency That Could Be Harming Your Health January 19, 2015
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Natural Medicines Comprehensive Database
Nielsen FH1, Johnson LK, Zeng H. Magnesium supplementation improves indicators of low magnesium status and inflammatory stress in adults older than 51 years with poor quality sleep. Magnes Res. 2010 Dec;23(4):158-68. doi: 10.1684/mrh.2010.0220. Epub 2011 Jan 4.
LINUS PAULING INSTITUTE Micronutrient Information Center
Megan Ware RDN LD Magnesium: Health Benefits, Facts, Research. Medical News Today
Kathryn Kos. Magnesium Deficiency & Soda. January 1, 2015.
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(2 votes, average: 4.00 out of 5, rated) Article last updated on: June 26th, 2018 by Nootriment