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9 Signs You Have Magnesium Deficiency and How to Treat It

By Dr. Josh Axe, DC, DNM, CN


Magnesium is arguably the most important mineral in the body, which is why magnesium deficiency can be such an issue.

According to Norman Shealy, MD, Ph.D, an American neurosurgeon and a pioneer in pain medicine, “Every known illness is associated with a magnesium deficiency and it’s the missing cure to many diseases.” Not only does magnesium help regulate calcium, potassium and sodium, but it’s essential for cellular health and a critical component of over 300 biochemical functions in the body.

Even glutathione, your body’s most powerful antioxidant that has even been called “the master antioxidant,” requires magnesium for its synthesis. Unfortunately, most people are not aware of this, and millions suffer daily from magnesium deficiency without even knowing it.

Causes of Magnesium Deficiency

Once thought to be relatively rare, magnesium deficiency is more common than most physicians believe. Here’s why:

  • Soil depletion, genetically modified organisms (GMOs) and the chemicals in our food have created a recipe for disaster. As minerals are removed, stripped away or no longer available in the soil, the percentage of magnesium present in food has decreased.

  • Digestive diseases, like leaky gut, can cause malabsorption of minerals, including magnesium. Today, there are hundreds of millions of people who aren’t absorbing their nutrients. Also, as we age, our mineral absorption tends to decrease, so the probability of having a deficiency increases across the board.

  • Chronic disease and medication use is at an all-time high. Most chronic illness is associated with magnesium deficiency and lack of mineral absorption. Medications damage the gut, which is responsible for absorbing magnesium from our food.

  • When you follow a keto diet, even if you’re drinking a lot of water, you will lose a lot of water weight and also flush essential electrolytes out of our system, including magnesium, potassium or sodium. This especially occurs in the beginning, so having magnesium-rich drinks like bone broth can help.

Should you worry about magnesium deficiency? It all depends on your risk factors and presenting symptoms (see below). Also, approximately 80 percent of people have low levels of magnesium, so the chances are that you’re probably deficient.

Take note: Only 1 percent of magnesium in your body is in your bloodstream, so often you can have a deficiency, and it would not even be discovered by a common blood test.

Related: What You Need to Know About the Most Common Nutrient Deficiencies in Women

Magnesium Deficiency Symptoms

Many people may be magnesium deficient and not even know it. Here are some key symptoms to look out for that could indicate if you are deficient:

1. Leg Cramps

Seventy percent of adults and 7 percent of children experience leg cramps on a regular basis. Turns out, leg cramps can more than a nuisance — they can also be downright excruciating! Because of magnesium’s role in neuromuscular signals and muscle contraction, researchers have observed that magnesium deficiency is often to blame. (2)

More and more health care professionals are prescribing magnesium supplements to help their patients. Restless leg syndrome is another warning sign of a magnesium deficiency. To overcome both leg cramps and restless leg syndrome, you will want to increase your intake of both magnesium and potassium.

2. Insomnia

Magnesium deficiency is often a precursor to sleep disorders, such as anxiety, hyperactivity and restlessness. It’s been suggested that this is because magnesium is vital for GABA function, an inhibitory neurotransmitter known to “calm” the brain and promote relaxation. (3)

Taking around 400 milligrams of magnesium before bed or with dinner is the best time of day to take the supplement. Also, adding in magnesium-rich foods during dinner — like nutrition-packed spinach — may help.

3. Muscle Pain/Fibromyalgia

A study published in Magnesium Research examined the role magnesium plays in fibromyalgia symptoms, and it uncovered that increasing magnesium consumption reduced pain and tenderness and also improved immune blood markers. (4)