Magnesium in large, bioavailable doses can relieve headaches and migraine

Magnesium deficiencies are rather common and can easily occur if you get too little magnesium from your daily diet. It has been known for a long time that lack of magnesium can cause tension headache and migraine. In fact, many randomized, double-blind studies show that high-dose magnesium supplements can relieve both migraine and headaches, provided the supplements have good bioavailability so the magnesium can enter the cells, where it controls a dozen of enzyme processes. A review article written by Italian scientists from Milan and published in the journal Nutrients takes a closer look at this.

In most cases, headaches and migraine occur independently of other conditions or diseases. This is also the case with Horton’s disease (cluster headache). It is well-known that these types of headache and migraine headaches are often triggered by stress and hormonal changes associated with PMS and menopause. According to the authors behind the new review article, magnesium supplements may be a useful alternative to traditional painkillers that are associated with side effects. What is more, a magnesium supplement compensates for the deficiency that is the underlying cause of the of the headache or the migraine. Magnesium is a simple and rather obvious type of therapy, which most people (including children, pregnant women, and seniors) can take without any problems.

Magnesium has many functions and is concentrated primarily inside the cells

Magnesium is one of the minerals that we need in the greatest quantities. It is of vital importance to nerve impulses, muscle contraction, blood pressure, blood sugar, bones, DNA synthesis, maintenance of the electrolyte balance, vitamin D activation, and many other things.
Around half of the body’s magnesium is stored in our bones. The remaining part is found in nerve cells, muscle cells, the liver and other soft tissues. We have nearly all of our magnesium inside the cells, where it fuels well over 300 different enzyme processes.
For over 20 years, science has described the different magnesium transporters and magnesium channels in the cell membranes, but it remains a mystery how magnesium works inside the cells. This is what the authors have taken a closer look in their article in Nutrients.

Absorption and regulation of magnesium levels in the blood

Magnesium is absorbed in the small intestine. In the kidneys, 80 percent of the magnesium in our blood is filtered by the glomerulus, which is a network of blood capillaries, through which our urine is excreted. More than 95 percent of the filtered magnesium is reabsorbed by this system. If there is too little magnesium, a higher quantity of the nutrient is reabsorbed, whereas less is reabsorbed if magnesium levels are adequate. In the case of severe magnesium deficiency, the bones serve as a mineral bank, from where magnesium is withdrawn and circulated in the bloodstream.
That way, magnesium levels in the blood are carefully managed in a concept that involves the uptake in the small intestine and excretion from the kidneys, with the bones serving as a buffer. But even though the body has several mechanisms for regulating its magnesium levels in the blood, deficiencies are surprisingly common.

Sources of magnesium and reasons why deficiencies are widespread

You get magnesium from kernels, almonds, nuts, seeds, beans, whole grain, cabbage, and many other vegetables. Most people in the Western countries do not reach the recommended intake levels for magnesium (375 mg/day in Denmark), which is primarily due to nutrient-depleted soil, refined foods, and unhealthy eating habits. Deficiencies may also be caused by poor absorption or increased magnesium excretion from the kidneys. Stress, stimulants, and medicine may also increase the need for magnesium.
It is difficult to measure the body’s magnesium levels, as only approximately one percent of the nutrient is found in our blood, while the remainder is concentrated inside our cells. The best way to determine the body’s magnesium status is to conduct a so-called whole blood analysis that measures the intracellular magnesium content. In some cases, a magnesium deficiency may be masked if the bones are able to deliver magnesium to the blood. This may continue for a period, but the risk of osteoporosis eventually increases because the bones need magnesium for their absorption of calcium.

Why use magnesium supplements if you have headaches or migraine?

Magnesium helps prevent or relieve headaches and migraine by way of several mechanisms. As mentioned earlier, magnesium is involved in over 300 different enzyme processes that are vital for proper functioning of cells, including nerve cells. A lack of magnesium may disrupt the body’s release of certain neurotransmitters, the constriction of blood vessels, muscle contraction etc., thereby resulting in headaches and migraine, including migraine with aura.
One of magnesium’s main functions is to serve as a door bolt in the calcium channels of the cell membranes. In bone cells, magnesium makes sure that most of the calcium is channeled into the cells. However, in cells in soft tissues like muscles and nerves, where the calcium concentration must be limited to a minimum, magnesium does the opposite by making sure that most of the calcium stays on the outside. If you lack magnesium, the calcium channels are left open and you risk that the nerve cells (and cells in other soft tissues) are flooded by calcium ions. This may overstimulate the nerve cells and cause them to cramp or malfunction in other ways.
Magnesium is involved in the control of NDMA glutamate (N-methyl-D-aspartate) receptors in the nerve cells that are important for pain transmission in the nervous system. Magnesium also helps regulate the cerebral blood flow and prevent local inflammation. Magnesium deficiencies are therefore involved in a host of neurological diseases, including Alzheimer’s disease and Parkinson’s disease.

Magnesium supplement as an effective therapy

Multiple studies show that patients with headaches and migraine have too little magnesium in their blood, spinal fluid, and certain parts of the brain. This also goes for patients suffering from migraine with aura. Researchers have pointed out that these patients may have systemic magnesium deficiency. The therapeutic effect of giving magnesium supplements to patients suffering from headaches has been documented in numerous double-blind, placebo-controlled, randomized studies.
It is already known that magnesium levels in the red blood cells of women suffering from premenstrual syndrome (PMS) are lower than in women without this condition. In a study of 20 women with PMS-related migraine, one half got 360 mg of magnesium from the time of ovulation until the beginning of their menstrual period over two cycles, while the other half got placebo. Magnesium turned out to reduce both the frequency and severity of headaches when evaluated through a pain index.
In another study, 81 migraine patients were either given 600 mg of magnesium daily or matching placebo for a period 12 weeks. In the period between the ninth and 12th week, the migraine attacks were reduced by 41.6% in the magnesium group and only 15.8% in the placebo group.
A study of children and youngsters aged 2-17 years, where the participants got magnesium in a daily dose of 9 mg per kilogram of body weight or matching placebo, revealed that the supplement had significantly reduced the number of days with headache.
A meta-analysis from 2016 also showed that magnesium supplementation had a therapeutic effect. The meta-analysis included 11 studies, in which patients with acute migraine attacks received intravenous magnesium, and 10 studies where the scientists looked at magnesium’s preventive effect on migraine. By and large, the meta-analysis demonstrated that magnesium has a positive effect in the acute and preventive treatment of migraine, and that magnesium supplementation is able to reduce the number of days with migraine by 22-43 percent.
According to the recent review article in Nutrients, several studies suggest that magnesium supplements not only reduce the number of days with headaches and migraine attacks but also their duration and severity, and it even helps reduce the need for acute medication.
Usually, daily doses of 360-600 mg are given to adults, and the optimal effect is normally seen after a few weeks.
The authors also mention a study where magnesium given to migraine patients did not have any effect and actually caused side effects such as diarrhea, but that was due to the fact that the supplement had poor absorption. It is imperative always to take high-quality magnesium supplements that are easily absorbed in the small intestine, so the magnesium can enter the cells.

The quality of supplements is crucial

Magnesium deficiency is normally treated with magnesium salts that are either organic or inorganic as listed below:

Inorganic magnesium salts:

• Magnesium carbonate, magnesium chloride, magnesium oxide, magnesium sulphate

Organic magnesium salts:

• Magnesium acetate, magnesium aspartate, magnesium citrate, magnesium gluconate, magnesium lactate, magnesium pidolate

Some magnesium supplements contain a blend of organic and inorganic magnesium sources, which gives better utilization. Some magnesium supplements are absorbed better than others. If the tablets pass through the digestive system without dissolving, you cannot expect them to work. A good way to test this is to drop a magnesium tablet into a glass of water to see how fast it dissolves. If it dissolves within less than a minute, you are pretty much guaranteed that the body can absorb the magnesium content in the small intestine.
Just for the record, magnesium oxide that is found in various supplements and in the laxative called Magnesia has poor bioavailability.
According to the listed studies, migraine patients can take a 200 mg supplement of magnesium three times daily with a main meal for 12 weeks or longer if it appears to have a positive effect.

References:

Jeanette A. Maier et al. Headaches and Magnesium: Mechanisms, Bioavailability, Therapeutic Efficacy and Potential Advantage of Magnesium Pidolate. Nutrients. 2020

Anna E. Kirkland et al. The Role of Magnesium in Neurological Disorders. Nutrients 2018

Andrea Rosanoff et al. Essential Nutrient Interactions: Does Low or Suboptimal Magnesium Interact with Vitamin D and/or Calcium status. Advances in Nutrition 2016

Mauskop A, Varughese J.: Why all migraine patients should be treated with magnesium. Journal of Neural Transmission 2012

A Peikert et al. Prophylaxis of Migraine with Oral Magnesium: Results from a Prospective, Multi-Center, Placebo-Controlled and Double-blind Study. Cephalalgia 1996

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