Magnesium is an essential mineral for our overall health, meaning it is required for normal body function and must be obtained from our diet or supplementation. Yet many people consume less than the recommended daily allowance (RDA) of magnesium making magnesium deficiency one of the top micronutrient deficiencies in the United States.
Magnesium and Health
Magnesium is needed for many different roles and functions, including assisting in over 300 enzymatic reactions in our body. Magnesium helps regulate glucose levels and blood pressure, produce energy, form our DNA, RNA, and support detoxification. It also plays a role in the active transport of calcium and potassium ions across cell membranes, which is important to nerve impulse conduction, muscle contraction, and normal heart rhythm.
Magnesium is involved in bone formation and influences the activities of osteoblasts and osteoclasts. Magnesium also affects the concentrations of both parathyroid hormone and the active form of vitamin D, which are significant regulators of bone homeostasis. Several population-based studies have found positive associations between magnesium intake and bone mineral density in both men and women.
While most of us understand that electrolytes like sodium and potassium are essential for our muscles, magnesium is also needed to synthesize protein and help our muscles to contract and relax. Magnesium deficiency can lead to muscle weakness and cramps.
Our heart is a muscle too. Not only is magnesium needed for our skeletal muscles, but also for our cardiac muscles to help our heart pump blood to all our organs and limbs efficiently. Magnesium deficiency can lead to high blood pressure, heart disease, and arrhythmias such as atrial fibrillation.
For nerve conduction to occur, magnesium transports potassium and calcium across our cell membranes. Magnesium deficiency can cause numbness and tingling in our extremities.
Our mitochondria are the powerhouses of our cells to produce energy. Mitochondria also stores magnesium and uses this mineral to create ATP, which is our energy source. Magnesium deficiency can cause fatigue if our cells cannot efficiently produce energy.
How is Magnesium Absorbed & Eliminated
Magnesium comes from our food when it gets broken down in our stomach, then absorbed in our small intestines. The amount of magnesium in our blood is controlled by elimination from our kidneys.
RDA of Magnesium
The Recommended Dietary Amount (RDA) of magnesium per day is different for all stages of life and genders:
Birth-6 months: 30mg
7 months-1 year: 75mg
1-3 years: 80mg
4-8 years: 130mg
9-13 years: 240mg
Teens (14-18 years)
Adults (19-50 years)
Older Adults (51+ years)
Magnesium Deficiency Signs & Symptoms
Common symptoms and disorders of magnesium deficiency include:
- High glucose/diabetes
- High blood pressure
- Muscle cramps/aches
Magnesium Deficiency Possible Causes
Medications, lifestyle factors, and gut health all have the potential to interact with magnesium supplements or affect magnesium serum levels.
Diuretics cause the kidneys to get rid of extra fluid in the body to decrease blood pressure. Therefore, magnesium can be excreted in the fluid.
Proton Pump Inhibitors (PPIs)
Prescription proton pump inhibitor (PPI) drugs, when taken for prolonged periods, can cause hypomagnesemia. The FDA advises healthcare professionals to measure patients' serum magnesium levels before prescribing PPIs and to recheck magnesium levels periodically.
Theophylline adversely affects the metabolism and urinary excretion of magnesium, depleting total magnesium levels in the body.
Atrial Fibrillation Drugs
Digoxin, a medication to correct an irregular heart rate such as atrial fibrillation, can also deplete magnesium. Digoxin reduces tubular magnesium reabsorption, and in patients with congestive heart failure, this interaction may be cumulative with other causes of magnesium deficiency (diuretics, diet, poor intestinal absorption)
Oral contraceptives (or birth control pills) can deplete certain nutrients such as magnesium, selenium, zinc, B2, B6, B12, folate, Vitamin C, and Vitamin E. Research has shown total serum magnesium can be reduced after taking oral contraceptive pills. It is thought that the increased risk of blood clots on oral contraceptive pills is partially due to the change in the calcium to magnesium ratio.
We lose electrolytes such as sodium, potassium, chloride, and magnesium when we sweat. Most sports drinks containing electrolytes have sodium and potassium but not magnesium. Therefore, we must replenish our food's magnesium levels or supplements.
When we are under acute stress, our bodies use magnesium to release certain neurotransmitters and hormones, such as catecholamines, cortisol, corticotropin-releasing factor (CRF), and ACTH.
These neurotransmitters and hormones help our bodies to adapt to stress. However, if the stress continues after an acute event, our bodies will continue to release these chemicals and need magnesium. This can contribute to magnesium deficiency over time.
Because magnesium is absorbed in our small intestines, maintaining proper gut health is very important.
8 Different Types of Magnesium
Supplementing is an easy way to replenish magnesium in the body if we cannot get enough from our food. To understand which type of magnesium is best for each condition, we have reviewed the most commonly used forms of magnesium below.
Magnesium citrate is a form of magnesium that's bound with citric acid. It is one of the most bioavailable forms of magnesium that is easily absorbed in the intestines. This form does have mild laxative effects; therefore, it is helpful in patients who suffer from constipation.
One study showed that migraine sufferers' frequency was reduced by 41.6% when the participants took magnesium citrate.
Highlights: It's mainly used to raise magnesium levels and treat constipation in higher doses.
Magnesium glycinate is made from a combination of magnesium and the amino acid glycine. This form of magnesium is easily absorbed and may have calming properties. It is also one of the gentlest magnesium supplements on the stomach and usually doesn't cause gi distress associated with other magnesium types.
Glycine is often used as a standalone dietary supplement to improve sleep.
Practitioners commonly use magnesium glycinate to help increase depleted magnesium levels and reduce the effects of insomnia, anxiety, and stress.
Highlights: Easily Absorbed, used to raise magnesium levels and has a calming effect.
Magnesium oxide is a salt that combines magnesium and oxygen and is the most common type of magnesium produced and used in supplements but has poor absorption.
It is best used to help alleviate constipation, so it should not be taken if you have loose stools or diarrhea. It is also frequently used for short-term relief of uncomfortable digestive symptoms, such as heartburn and indigestion.
Highlights: Mainly used for constipation. Not suitable for raising magnesium levels due to poor absorption.
Magnesium chloride is a magnesium salt that includes chlorine and is easily absorbed via the digestive tract to raise magnesium levels or, topically, to relieve pain. One study showed women with fibromyalgia improved their symptoms after using magnesium chloride.
Highlights: Easily absorbed orally and topically. It is commonly used to raise magnesium levels and treat digestive complaints such as heartburn and constipation. Topically it may help relieve pain but is not proven to increase magnesium levels this way.
Magnesium malate includes malic acid, which occurs naturally in some foods like fruit and wine. This acid has a sour taste and is often used as a flavor enhancer.
Magnesium malate has excellent absorption and can increase magnesium levels in our red blood cells. It is gentler on digestion than some of the other magnesium supplements. Therefore it is commonly used with patients who already have a tendency towards looser stools.
This form of magnesium is occasionally recommended as a treatment for symptoms associated with fibromyalgia and chronic fatigue syndrome, although there is limited research on this. This smaller study showed a reduction in pain and tenderness in 24 patients who have fibromyalgia.
Highlights: Easily absorbed and gentler on digestion than other forms. It's occasionally recommended for chronic pain conditions.
Magnesium orotate is a combination of magnesium and orotic acid. It is easily absorbed because it is not broken down by our stomach acid. This type of magnesium increases magnesium levels and treats symptoms of heartburn and indigestion related to higher stomach acid levels. It has also been shown to have heart health-boosting properties. A downside to magnesium orotate is its cost, as it is significantly more expensive than other magnesium supplements.
Highlights: Easily absorbed and used to increase magnesium levels and boost heart health. Commonly used in athletes, but it is more expensive than other forms of magnesium.
Magnesium sulfate is formed by combining magnesium, sulfur, and oxygen. It is commonly used as an Epsom salt soak. It can be taken internally to be used to help relieve constipation but has an unpleasant taste. Therefore many people choose other forms of magnesium to treat constipation, like magnesium citrate.
Highlights: Although many people use this type of magnesium topically, there is little evidence that it is absorbed at high enough levels through the skin to raise blood serum magnesium levels. Therefore, this form is commonly used to help with pain relief and relaxation.
Magnesium taurate is a combination of magnesium and the amino acid taurine. This form of magnesium has excellent absorption and is sometimes used to improve blood pressure, preeclampsia in pregnant women, and insulin sensitivity, although human trials are limited.
Highlights: Not the most common magnesium supplement on the shelves, but there is a small amount of evidence that it may treat conditions associated with blood pressure and insulin sensitivity. More trials have been requested for these conditions.
Functional Medicine Labs to Detect Magnesium Deficiency
It can be hard to determine if you have magnesium deficiency based on symptoms alone. Therefore, functional medicine suggests testing for magnesium and other micronutrient levels annually. Checking your levels can help determine how much magnesium you need every day and whether those levels can be achieved via diet or if a higher dose in supplement form is required.
Most primary care providers check a serum magnesium level. The serum contains plasma, platelets, and red blood cells. Remember, less than 1% of magnesium is found in our blood because our cells get magnesium from our red blood cells. Therefore, the Magnesium RBC test is a more accurate assessment of the amount of magnesium detected in your red blood cells.
Functional lab tests such as the NutrEval by Genova Diagnostics check Magnesium RBC and other nutrient levels that could affect magnesium absorption. The Micronutrients Panel by Vibrant America checks not only Magnesium RBC but also the intracellular and extracellular levels.
Since most Americans are deficient in magnesium, which can be a factor leading to multiple chronic diseases, it is essential to get your levels checked. Consuming more avocados, beans, nuts, whole grains, seeds, and salmon are excellent sources of magnesium in our food.