How do you feel when your magnesium is very low?

The mild and moderate stages, how each feels, and the causes that produce them

How you feel when your magnesium is very low depends on how low, and the honest picture has three stages that feel different and come from different causes. The mild stage, a shortfall rather than a disease: a lifter on a cut that dropped the nuts and greens, a rice-and-chicken bulk or a generally light plate feels tired in a way that sleep does not quite fix, notices calf or foot cramps at night and twitches in an eyelid or a calf, sleeps less well and feels a little more wound up than the training week explains, the register's fatigue, muscle-function, nervous-system and psychological-function sentences describing in reverse what the shortfall is quietly costing, and the picture being vague enough that most readers in it never connect it to a mineral, which is the diet audit's purpose. The moderate stage, clinical hypomagnesaemia: a serum magnesium below the reference range, produced by heavy drinking, a proton-pump inhibitor taken for years, a loop or thiazide diuretic, chronic diarrhoea or malabsorption, poorly controlled diabetes or a diet that ran badly light for a long time, and it feels worse and stranger, a fine tremor in the hands, muscle weakness that makes stairs and lifts harder, nausea and a lost appetite, numbness and tingling in the hands and feet and around the mouth, and a change in mood and personality, irritability, apathy, low mood or a sense of not being oneself that family notice before the reader does, with low potassium and low calcium often travelling with it and adding their own signs, the hypomagnesaemia page's picture and a GP's blood panel's finding.

The severe stage, the test that finds it, the recovery, and the picture filed

The severe stage is a hospital picture and a reader in it is not reading this page: tetany, the sustained painful spasm of hands, feet and face that severe low magnesium and its accompanying low calcium produce; an irregular heartbeat, palpitations and the arrhythmias that make severe hypomagnesaemia a cardiac emergency; confusion, delirium and, in the worst cases, seizures, since severe low magnesium lowers the seizure threshold, all of which are treated with intravenous magnesium under monitoring and none of which a capsule touches. The test that finds it is simple: a serum magnesium, added to a GP's routine electrolyte panel on request or when the history suggests it, with the honest note that serum is defended and can read normal while tissue is short, so a normal serum in a reader with the mild stage's signs on a light diet does not rule a shortfall out and the diet audit still applies, while a low serum is a definite finding with a cause to find. The recovery follows the three clocks, serum in days, tissue in four to eight weeks, and the feelings reversing in the order they came, the twitches and cramps first, the tremor and weakness next, the fatigue, sleep and mood over the weeks, and it holds only if the cause is closed, the drinking, the medicine, the gut, the glucose or the plate. The picture filed: mild is tired, crampy, twitchy, sleeping badly and a little more anxious, on a light diet; moderate is tremor, weakness, nausea, numbness and a changed mood, on a low serum with a clinical cause; severe is tetany, arrhythmia, confusion and seizures, in hospital, with a serum magnesium finding it and repletion reversing it once the cause is closed, the worked example being for the mild stage by audit, bisglycinate at 300mg elemental, £19.99 for 90 days at 22p, and the moderate and severe stages being a doctor's.

The verdict, three stages that feel different and one test that finds them

How do you feel when your magnesium is very low: in the mild stage, tired, crampy, twitchy, sleeping badly and a little more anxious, the vague picture of a shortfall on a light diet that the diet audit exists to catch; in the moderate stage of clinical hypomagnesaemia, a fine tremor, muscle weakness, nausea and lost appetite, numbness and tingling and a changed mood, from alcohol, medicines, gut loss or diabetes and found on a serum magnesium; and in the severe stage, tetany, an irregular heartbeat, confusion and seizures, a hospital picture treated with intravenous magnesium, with recovery reversing the feelings in the order they came once the cause is closed. For the mild stage by audit: Futuro Labs Magnesium Glycinate, bisglycinate, 300mg elemental at 80% NRV, £19.99 for 90 days at 22p a day.

What to check on the label

Questions people also ask

What are the first signs of low magnesium?

Fatigue that sleep does not quite fix, night cramps in the calves or feet, twitches in an eyelid or a calf, poorer sleep and feeling a little more wound up than the week explains, the mild stage of a shortfall on a light diet.

What does severe magnesium deficiency feel like?

Clinically low magnesium brings a fine tremor, muscle weakness, nausea and a lost appetite, numbness and tingling and a changed mood, and at its most severe tetany, an irregular heartbeat, confusion and seizures, which is a hospital emergency treated with intravenous magnesium.

Can low magnesium change your mood or personality?

Yes in clinical hypomagnesaemia: irritability, apathy, low mood or a sense of not being oneself that family often notice first, alongside the physical signs, with the register's psychological-function sentence describing what repletion restores.

How is low magnesium diagnosed?

A serum magnesium added to a GP's routine electrolyte panel, with the note that serum is defended and can read normal while tissue is short, so a low result is definite and a normal one does not rule out a mild shortfall on a light diet.

What causes magnesium to get very low?

Heavy alcohol, proton-pump inhibitors taken for years, loop and thiazide diuretics, chronic diarrhoea or malabsorption, poorly controlled diabetes and a diet that ran badly light for a long time, each a cause to close before repletion holds.

Sources

1. The hypomagnesaemia literature: clinically low serum magnesium presents with cramps, tremor, weakness and, when severe, arrhythmias and seizures, with alcohol misuse, proton-pump inhibitors, diuretics and gastrointestinal loss the common causes, and serum magnesium an imperfect marker of tissue status. PubMed record
2. The magnesium and neuromuscular junction physiology: magnesium antagonises calcium at the presynaptic terminal and reduces acetylcholine release, so magnesium excess depresses neuromuscular transmission and produces weakness, while magnesium deficiency increases neuromuscular excitability and produces twitching, cramps and tetany. PubMed record
3. The magnesium repletion literature: supplementation in adults with low status raises serum and intracellular magnesium over four to eight weeks, and trials reporting functional outcomes have dosed daily for four to twelve weeks. PubMed record
4. The renal magnesium handling literature: the kidney is the main regulated exit for magnesium, reabsorbing most filtered magnesium in the loop of Henle and distal tubule and excreting the surplus, with loss increased by alcohol, loop and thiazide diuretics, high glucose and certain drugs. PubMed record

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