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Magnesium deficiency

2-minute read

What is magnesium deficiency?

Magnesium deficiency is when the body does not get all the magnesium it needs for health.

Health problems linked to magnesium deficiency are rare, but if your magnesium levels are low long-term due to other health conditions like alcoholism or taking some medications, you may be at greater risk.

Magnesium deficiency can lead to health problems including:

What are the symptoms of magnesium deficiency symptoms?

Magnesium deficiency can cause:

  • loss of appetite
  • nausea and vomiting
  • fatigue and weakness
  • shaking
  • pins and needles
  • muscle spasms
  • hyperexcitability
  • sleepiness
  • abnormal heart rhythms

What causes magnesium deficiency?

Magnesium deficiency in healthy people is rare but it can be caused by:

  • a poor diet (especially in elderly people or those who don’t have enough to eat)
  • type 2 diabetes
  • digestive problems such as Crohn’s disease
  • long-term vomiting or diarrhoea
  • kidney problems
  • long-term use of diuretics
  • some medicines (for example, fluid tablets and medicines for ulcers or reflux) can cause low magnesium levels if taken for long periods
  • alcoholism

Sometimes, people can take in too much magnesium in antacids or laxatives, but this is rare. If you have concerns about this, check with your pharmacist or doctor.

How is magnesium deficiency diagnosed?

Magnesium deficiency is diagnosed via a blood test and sometimes a urine test. Your doctor may order the blood test if you have symptoms such as weakness, irritability, abnormal heart rhythm, nausea and/or diarrhoea, or if you have abnormal calcium or potassium levels.

How is magnesium deficiency treated?

If you have magnesium deficiency, your doctor will prescribe a magnesium supplement. Sometimes these can give you diarrhoea, so your doctor may need to experiment with the dose. In severe cases, intravenous magnesium may be needed.

Make sure you consult with your doctor if you are thinking of taking a magnesium supplement, as it’s possible to take too much magnesium. Taking more than the recommended dose can cause vomiting, diarrhoea, abdominal cramps and, in extreme cases, irregular heartbeat and cardiac arrest.

How do you prevent magnesium deficiency?

To prevent magnesium deficiency, it is important to eat a healthy, balanced diet containing magnesium-rich foods such as leafy green vegetables, legumes, nuts, seeds and whole grains.

Learn more here about the development and quality assurance of healthdirect content.

Last reviewed: March 2021


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