What is the link between magnesium deficiency and headaches?

What role does magnesium play in the nervous system?

Magnesium acts as a cofactor in more than 300 enzymatic reactions and plays a central role in how the nervous system works. It modulates the activity of NMDA receptors to glutamate and stabilises the excitability of neuronal membranes, which helps to temper excessive nervous activity^[1]. On this physiological basis, the EFSA authorises the claim that “magnesium contributes to normal nervous function”^[3].

Neuronal excitability and vascular tone

Two mechanisms connect magnesium to headaches. On the one hand, by regulating the flow of calcium and potassium across membranes, magnesium influences the excitability threshold of neurons. On the other hand, it takes part in regulating the tone of blood vessels, whose dilation and contraction play a part in the physiology of migraine^[2]. These roles explain the research interest in this mineral, without making it a treatment in its own right.

Magnesium deficiency and headaches: what does the science say?

A low magnesium status is observed more often in some people with migraine, and several guidelines consider magnesium a possible option for migraine prevention, with a moderate level of evidence^[2]. A measured view is needed, however: it is one factor among others, and the effect, where it exists, remains partial.

One factor among others

Frequent headaches most often result from a combination of factors: lack of sleep, stress, dehydration, muscular tension, prolonged screen exposure or caffeine withdrawal. Attributing a headache to a single “magnesium shortfall” would be reductive. The mineral may be part of the picture, particularly in people whose intake is genuinely insufficient, but it replaces neither a diagnosis nor appropriate care.

Signs that may accompany a shortfall

When a shortfall is involved, headaches are often accompanied by other non-specific signals:

• Unexplained fatigue and a drop in day-to-day energy.
• Irritability or nervousness that increases in the face of stress.
• Muscle cramps or twitches, including small eye spasms.

As these symptoms are common to many situations, only a healthcare professional can determine whether a magnesium shortfall is genuinely involved, with a blood test if needed.

How can you improve your magnesium intake?

If your intake is insufficient, diet remains the first lever. Regularly eating magnesium-rich foods generally covers an adult’s needs, estimated at around 300 to 400 mg per day depending on age and sex^[1]. To go further on the whole topic, see the complete magnesium guide.

Rely on diet first

The most valuable natural sources are leafy green vegetables (spinach), nuts and seeds (almonds, walnuts), seeds (pumpkin, sunflower), legumes and whole grains. Dark chocolate also provides some. Magnesium from food does not pose a risk of overdose, unlike high-dose supplements.

When should supplementation be considered?

If diet is not enough, supplementation can be discussed, preferably in a well-absorbed form such as bisglycinate or citrate, and after medical advice to set the dose. Magnesium can interact with certain medicines, and an excess mainly causes digestive upset^[4]. It is therefore better to correct a confirmed shortfall than to supplement “blindly” in the hope of making a headache disappear.

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