The Signs Of Magnesium Deficiency & What To Do About It

Magnesium is an essential mineral that keeps our bodies running smoothly. Normal serum (blood) magnesium levels1 are defined as 0.75 to 0.95 mmol/L, with anything below this range indicating potential deficiency known as hypomagnesemia. While only 2% of the population2 is reported as having hypomagnesemia, some health professionals say that the condition is severely under-diagnosed since magnesium levels are usually only tested when they get dangerously low.

If you're concerned about your magnesium levels (which tend to decline with age), here are the most common symptoms of a deficiency, how to test your levels, and what to do about it.

Magnesium deficiency can be hard to diagnose, but if you suffer chronically from two or more of these symptoms, it's a clue that further testing might be needed.

Fatigue and exhaustion are generalized symptoms. You may attribute your tiredness to stress, poor sleep, or a host of other reasons and not realize just how much nutrition is playing a role. According to research on chronic fatigue syndrome3, magnesium provides nutritional support to combat fatigue. This is because magnesium is required for the production of energy. If the body has inadequate access to magnesium, then energy production suffers, leaving you prone to fatigue.

Although inflammation is a necessary part of immune function and wound healing, chronic inflammation underlies many major diseases like heart disease and diabetes. Inflammation can feel like hot and swollen localized areas on the body, generalized aches and pains, overall feeling lousy or tired, or show up as an inflammatory diagnosis. 

Magnesium plays a key role in managing the body's normal inflammatory response. When magnesium intake is low, inflammatory biomarkers such as high-sensitivity c-reactive protein (hs-CRP), interleukin-6, and fibrinogen4 are significantly affected. In fact, a large study of a Nordic diet5 providing magnesium-rich foods, such as whole grains and vegetables, reduced the pro-inflammatory protein known as Interleukin-1.

Although blood sugar (glucose) levels are no doubt heavily influenced by what you eat and how much energy you expend, surprisingly they are also influenced by magnesium levels. This is because magnesium assists the body in glucose and insulin metabolism.

A large six-year study found that low serum magnesium levels were associated with insulin resistance and risk of prediabetes. In addition, it found that common variations in magnesium-regulating genes6 that cause low serum magnesium were associated with increased risk for diabetes.  Unfortunately, the onset of diabetes might compound the problem because it increases urinary magnesium excretion7.

Although the mechanisms aren't well understood, there is anecdotal and some limited published evidence that low magnesium levels can cause restless leg syndrome8 (RLS). 

Magnesium supplementation has been found to help manage symptoms of RLS9, leg cramps, and even periodic limb movement disorders. Magnesium might be most beneficial in muscle cramps related to pregnancy10; however, more research is needed.

More than 40 million Americans' quality of life is affected by their daily struggles with social stress, fear, and apprehension. Maintaining normal magnesium levels could help manage stress due to magnesium's beneficial interaction with the brain.

Magnesium is important for the regulation of the "feel-good" neurotransmitters dopamine and serotonin as well as the stress response. In other words, low brain magnesium11 means serotonin levels are reduced, which can present as mood swings. Studies back this up, showing that low levels of magnesium intake12 are associated with mood disorders.

Migraines are the sixth-most disabling illness worldwide, causing hours and days of recurring pain, sensitivity to light and sound, and even nausea and vomiting. A large body of evidence has found that magnesium, whether administered orally or via IV, can be an effective and inexpensive option13 for providing nutritional support in the management of migraines.

Although the mechanisms aren't fully understood, it is known that maintaining a normal magnesium level helps preserve the electrical function of brain neurons.

Magnesium is a mineral and electrolyte that the body requires to maintain normal nerve and electrical impulses of the heart.* Heart flutters, elevated or slow heart rate, and a "racing" heartbeat are all signs of a possible magnesium deficiency.

In addition, reduced magnesium intake, as well as low serum levels, have been shown to have an adverse effect on multiple aspects of cardiovascular health14. According to a meta-analysis, an extra 100 mg of magnesium a day15 in the diet was associated with cardiovascular health.

If you are concerned about your magnesium levels, there are several lab tests you can discuss with your health care provider. A serum magnesium blood test can be obtained with a quick and simple blood draw, although it can be a poor indicator of magnesium levels because 99% of magnesium resides within your cells and tissue16.

Urinary magnesium excretion, obtained via a 24-hour urine collection, might be a more accurate assessment tool, but it can be cumbersome. A magnesium retention (or "loading") test is also more reliable than blood testing but requires measurement of bone magnesium after an oral or IV magnesium dose.

While you'll need formal testing to know if you’re clinically deficient, you can also add more magnesium-rich foods to your diet or try a magnesium supplement to see if your symptoms improve.

Several foods contain magnesium, especially dark leafy greens, nuts, seeds, legumes, and whole grains. To get the 320 to 420 mg of magnesium per day that the National Academies recommend, you also might want to consider talking to your doctor about taking a magnesium supplement.

There are several different forms of supplemental magnesium, but the glycinate, citrate, chloride, lactate, and aspartate17 forms are best absorbed by the body, though some of them are associated with issues like bloating and diarrhea. Magnesium glycinate is less likely to cause side effects and has the added benefit of promoting deeper and more restorative sleep and early research shows it also might help with stress relief.

Magnesium is an important mineral that protects our organs, DNA and cell integrity, helps our bodies produce energy, helps maintain the body’s normal inflammatory responses, and supports normal blood pressure and blood sugar levels.

Despite several delicious and easy-to-eat foods that supply ample magnesium, like nuts, seeds, beans, dark leafy greens, and whole grains, supplementation may be ideal.

If you suffer chronically from any of the symptoms listed above, then magnesium supplementation could be beneficial. Aim to consume 300 to 420 mg of magnesium per day from a combination of food and supplements, or more for a diagnosed deficiency.