Magnesium deficiency
Linked to Magnesium
Low magnesium can trigger cramps, fatigue and heart-rhythm problems.
Where it shows on the body
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Causes
- Low intake
- High alcohol use
- Gut or kidney disorders
- Some medications (diuretics)
Symptoms
- Muscle cramps and twitches
- Fatigue
- Irregular heartbeat
- Low mood
- Numbness
What happens if untreated
- Seizures and dangerous heart rhythms in severe cases
- Worsens low calcium and potassium
Who is most at risk
- Heavy drinkers
- People with digestive disease
- Users of certain medicines
Prevention & sources
- Nuts, seeds, wholegrains and greens
- Supplements if advised
Correcting it: foods, amounts & timing
Foods that help & safe amounts
- Nuts, seeds, wholegrains, beans and leafy greens daily
- Around 300–400 mg/day for adults; supplements can cause diarrhoea, so keep to advised doses
Time to see benefits
Cramps and fatigue usually ease within 1–4 weeks.
Sources & references
Symptoms overlap — testing matters
Most deficiency symptoms (fatigue, poor concentration, skin and hair changes) are shared across several nutrients and many unrelated conditions. A symptom on this page is a reason to investigate, not a diagnosis.
A GP can confirm or rule out a deficiency with a blood test and check for underlying causes such as absorption problems. Do not start high-dose supplements on suspicion alone — some nutrients are harmful in excess, and supplementing before testing can mask the underlying result.
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