Magnesium - are you deficient?

There is just so much to the topic of magnesium. It's crucial in hundreds of processes in your body, and almost all diseased states show a deficiency in this essential mineral. I want to go over some of the signs of deficiency.

With that in mind - deficiency is genuinely common, frequently missed, and the symptoms are so varied that most people never connect them to a single underlying cause. You can be deficient for years and just assume you're stressed, getting older, or not sleeping well enough.

Let me walk you through some warning signs.

Muscle cramps and twitches

This is the classic one. If you're getting leg cramps at night, muscle spasms, or that annoying eye twitch that won't quit - low magnesium is one of the first things to consider. Magnesium is essential for muscle relaxation. Without enough of it, muscles struggle to release properly after contracting. Your calves cramping at 3am is your body sending a fairly loud message.

You can't sleep - or you can't stay asleep

Magnesium regulates melatonin production and activates the parasympathetic nervous system - the part responsible for rest and recovery. Low magnesium means your nervous system has a harder time downshifting at night. If you lie awake with your brain running, or you wake up in the early hours and can't get back to sleep, magnesium deficiency is worth investigating before you resign yourself to being 'just a bad sleeper.'

Anxiety that feels physical

There's a difference between anxious thoughts and anxious physiology - racing heart, tight chest, that wired and on-edge feeling that doesn't have an obvious cause. Magnesium plays a direct role in regulating the nervous system's stress response. When you're low, your nervous system is essentially running without adequate brakes. If anxiety feels more physical than psychological, this is worth paying attention to.

Chronic fatigue

Not just tiredness - the kind of fatigue that sleep doesn't fix. Magnesium is required for the production of ATP, which is your cells' energy currency. Every cell in your body uses it. If you're running low on magnesium, your cellular energy production is compromised at a fundamental level. This isn't about motivation or lifestyle - it's biochemistry.

Headaches and migraines

Magnesium deficiency is one of the most well-documented triggers for migraines, and it's been studied extensively in that context. Low magnesium causes blood vessels to constrict and affects neurotransmitter function - both relevant to migraine development. If you're a regular migraine sufferer who has never looked at magnesium, this is probably the most important thing you'll read today.

High blood pressure

Magnesium helps blood vessels relax and dilate. Without enough of it, vessels stay more constricted than they should, and blood pressure creeps up. If your blood pressure is elevated and you're not sure why, or you're trying to support it naturally, magnesium is one of the first nutrients to assess.

Constipation

Magnesium draws water into the intestines and helps the smooth muscle of the gut contract and relax properly. Low magnesium = sluggish digestion. If this is a chronic issue for you, your gut may be telling you something your doctor hasn't mentioned.

Brain fog and poor memory

Magnesium is involved in hundreds of enzymatic processes in the brain. Low levels affect neurotransmitter function, synaptic plasticity, and the brain's ability to form and retrieve memories. If your thinking feels slow, you're forgetting things more than you used to, or you can't concentrate the way you once could - magnesium deficiency is a legitimate possibility, not just aging.

Heart palpitations

Irregular heartbeat or the sensation of your heart skipping or fluttering can be a sign of low magnesium. The heart muscle depends on magnesium for proper electrical signalling and relaxation between beats. 

Why are so many people deficient?

A few reasons. Modern farming has depleted soil magnesium levels significantly, so even people eating plenty of vegetables are getting less than previous generations did. Stress depletes magnesium rapidly - and most people are under chronic stress. Alcohol, caffeine, and certain medications (including PPIs, diuretics, and some antibiotics) all accelerate magnesium loss. And because magnesium isn't routinely tested in standard blood panels - and serum magnesium isn't even the most accurate measure anyway - deficiency flies under the radar constantly.

If several of these resonate with you, it's worth taking seriously. The good news is that magnesium is one of the more straightforward nutritional gaps to address - but as I've covered already this week, the form you take matters. Different forms work better for different symptoms, which is why I put all seven that I use for ingestibles in one place.