Magnesium is one of the most important and most abundant minerals in the human body. A necessary cofactor in over 300 enzyme systems, magnesium plays a role in a wide variety of biochemical reactions, including protein synthesis, nerve function maintenance, blood glucose control, muscle contraction and normal heart rhythms. Its importance for overall bodily function cannot be underemphasized.
Unfortunately, an estimated 70-80 percent of Americans are deficient in this mineral, with similar rates of deficiency around the rest of the world. Furthermore, assessing magnesium levels within the body is difficult because most magnesium is inside cells or within bones, making lab tests through blood draws often inaccurate.
Soil erosion and society’s growing dependence on processed foods have caused many individuals to fall short of U.S. Food and Drug Administration’s recommended daily value of 400mg for adults and children aged 4 and older. As a result, many individuals are now turning to magnesium supplements in order to increase their intake of this critical mineral.
But one trip to the health food aisle of your local grocery store will quickly reveal a variety of forms of magnesium supplements, including magnesium oxide, citrate and chloride, among others. Not only does the absorption rate and bioavailability of magnesium from different forms vary, but certain forms also more strongly support particular bodily functions than others.
Before reaching for a supplement, however, it is important to note that obtaining key minerals and vitamins through nourishing whole foods is always preferable. Good sources of magnesium include green leafy vegetables (such as spinach), legumes, nuts, seeds and whole grains, as well as some breakfast cereals and other fortified foods. Unfortunately, only about 30-40 percent of dietary magnesium consumed is typically absorbed by the body, so supplementation in many cases may be necessary.
So which form is optimal? And how do you know which magnesium supplement is right for you? A helpful guide is below:
Magnesium Oxide: Often used in milk of magnesia products, this form has a strong laxative effect. It is the most common form of magnesium sold in pharmacies and contains a large proportion of magnesium, but due to poor bioavailability and unpleasant gastrointestinal side effects, it is one of the least optimal forms to use as a supplement.
Magnesium Citrate: The most popular magnesium supplement due to being inexpensive and easily absorbed. It is a good option for delivering magnesium to the body because it is rapidly absorbed in the digestive tract, but it does have a stool loosening effect.
Magnesium Sulfate: Found in Epsom salt, this form can be absorbed through the skin but is not used in oral formulations.
Magnesium Glycinate: Glycine is a well-known calming amino acid, and as one of the most bioavailable and absorbable forms of magnesium, magnesium glycinate can be used to enhance sleep quality. In addition, because glycine is actively transported through the intestinal wall, this formulation does not have a strong laxative effect. Perhaps the safest option for correcting a long-term deficiency, this combination also has been used successfully for chronic pain and muscle spasms.
Magnesium Malate: Because malate (in the form of malic acid) is a vital component of enzymes that play a key role in ATP synthesis and energy production, this formulation is the preferable choice for individuals suffering from fatigue. There is also preliminary evidence that this less well-known combination may reduce muscle pain and tender spots in fibromyalgia patients.
Magnesium Taurate: A popular choice for individuals with cardiovascular issues, since both magnesium and the amino acid taurine share the ability to improve cardiac function and guard the heart from damage caused by heart attacks. Magnesium and taurine also have blood pressure reducing effects, stabilize nerve cells and improve the contraction of the heart muscle.
Magnesium Chloride: This combination has one of the lowest percentages of magnesium (approximately 12%), but has a very strong absorption rate and is considered perhaps the best form of magnesium to aid in the removal of toxins from cells and tissues.
Magnesium Orotate: A new and relatively unknown combination containing orotic acid, this form has good bioavailability and has been shown to improve heart health, symptoms of angina and exercise performance in clinical trials. Orotates have been shown to penetrate cell membranes, allowing for effective delivery of magnesium to the inner layers of the cellular mitochondria and nucleus.
As you can see, there are a wide variety of formulations that have different therapeutic impacts, but any discussion of magnesium supplementation requires a few words of caution. First, while too much magnesium from food does not pose a health risk in healthy individuals because the kidney eliminate excess amounts through urine, high doses of magnesium from supplementation often results in diarrhea that can be accompanied by nausea and abdominal cramping.
Second, several types of medications (such as bisphosphonates, antibiotics, proton pump inhibitors and diuretics) have the potential to interact with magnesium supplements or affect magnesium status. Be sure to consult your physician or healthcare provider before using a magnesium supplement if you are currently taking prescription medication.