Magnesium is the fourth most common mineral in the body and an essential component of hundreds of daily enzymatic processes that occur across multiple organ systems. Based on NHANES data, the risk of inadequate intake is high. Magnesium is an essential mineral that we need to ingest through diet or supplementation. It is present in higher amounts in green leafy vegetables, pumpkin seeds, almonds, Brazil nuts, salmon, avocado, quinoa, legumes and dark (70%) chocolate.
Causes of Magnesium Deficiency
Unfortunately, even in those foods, magnesium levels seem to be declining due to soil nutrient depletion. In addition, many people are deficient in magnesium for other reasons, including the following:
Low amounts in the Standard American Diet (SAD)
Malabsorption, increased urinary excretion or bone loss in the elderly
Gastrointestinal disorders, such as IBD, celiac disease and chronic diarrhea
Alcohol abuse, which contributes to increased urinary excretion, poor diet and malabsorption
Excessive sweating, such as in athletes who exercise regularly
Finally, magnesium can also be low due to drug-induced nutrient depletion. This is seen with proton-pump inhibitors, diuretics, nephrotoxic drugs (e.g., digoxin, cisplatin and lithium), corticosteroids, birth control pills and macrolide antibiotics (e.g., azithromycin)—to name a few. If your patients take any of these medications, be sure to monitor their magnesium levels.
How Magnesium Affects the Body
Magnesium has pleiotropic effects on the body: it has been shown to reduce blood pressure, decrease cardiac arrhythmias, stop muscle cramps, improve sleep and relaxation, and reduce pain. It activates vitamin D, improves insulin sensitivity and supports mood by modulating GABA levels in the brain. It promotes both bone and brain health, aids digestion and supports methylation. Magnesium downgrades the stress response, which reduces cortisol levels. It also decreases oxidative stress by regulating NfR2 and NF-κB signaling pathways.
In terms of thyroid function, magnesium is necessary for the conversion of T4 to T3. It is also a co-factor in the production of diamine oxidase (DAO), which is the enzyme that degrades histamine, so deficiency results in higher histamine levels. Magnesium also decreases calcitonin gene-related peptide (CGRP) levels and thus may be helpful in treating and preventing migraines. As one practitioner noted, “Magnesium is helpful in my patients with 100 problems—even though it usually only helps 98 of them.”
Measuring Magnesium Levels
However, measuring magnesium levels can be tricky. Serum plasma levels are unlikely to be low as the body tightly regulates those levels. Intracellular or red blood cell magnesium is a better way to measure it. Organic acid testing (OAT) also helps to show the body’s need for magnesium.
Forms of Magnesium Supplementation
Mineral salts, such as magnesium oxide, tend to be poorly absorbed beyond the duodenum, are limited by passive diffusion, and must compete with other minerals and food for absorption. Mineral chelates instead use an active transport mechanism and absorb well throughout the GI tract, resulting in less diarrhea, a common side effect of magnesium. The following forms of magnesium may provide diverse benefits:
Magnesium citrate is helpful for constipation.
Magnesium threonate could be beneficial for cognitive function and mood disorders because it may cross the blood-brain barrier, based on some studies. However, further research is needed to substantiate these claims.
Magnesium sulfate (Epsom salts) is suitable for detoxification and muscle relaxation.
Magnesium taurate is useful for heart health and sugar balance.
Magnesium malate has been used for fibromyalgia pain.
Magnesium bisglycinate is helpful for pain, anxiety and insomnia.