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Magnesium and magnesium supplements

What is magnesium?

Magnesium is a mineral that's important for the body to turn food into energy and for bone health.

Although magnesium is available in supplements, most people should be able to get all the magnesium they need from a healthy balanced diet.

Magnesium health benefits and uses

There is some evidence that eating foods high in magnesium and other minerals may lower blood pressure. Magnesium supplements may help some people with heart disease, but the British Medical Journal cautions "We need bigger studies to find out for certain if taking magnesium can help to reduce blood pressure." Type 2 diabetes is also associated with low magnesium.

Intravenous or injected magnesium is used to treat other conditions, such as eclampsia during pregnancy and severe asthma attacks. Magnesium is also the main ingredient in many antacids and laxatives.

Magnesium deficiency

Experts say that many people do not eat enough magnesium-rich foods. This mild magnesium deficiency could put them at risk of a number of diseases such as:

Symptoms of magnesium deficiency include:

  • Nausea
  • Weakness
  • Irregular heartbeat ( arrhythmia)
  • Muscle twitching
  • Spasms
  • Irritability
  • Convulsions
  • Nystagmus (uncontrolled eye movement)
  • Writhing
  • Abnormal reflexes
  • Aggressive behaviour

Severe magnesium deficiencies are rare.

Low magnesium levels

If low magnesium levels are found, this is called hypomagnesaemia.

Reasons for this can include a lack of magnesium in the diet, the body not taking on board the magnesium from food, or the kidneys disposing of too much magnesium.

Low magnesium levels can be linked to conditions including:

  • Gastrointestinal problems, including Crohn's disease
  • Poorly managed diabetes
  • Underactive parathyroid gland
  • Long-term use of diuretics ('water tablets')
  • Burns
  • Post-operation complications
  • Pregnancy and toxaemia

High magnesium levels

It is unlikely someone would eat too much magnesium-containing food making levels rise, but overuse of supplements is possible.

Conditions linked with higher magnesium levels include:

What is a magnesium test for?

A test to measure magnesium levels in the blood may be arranged by doctors investigating some conditions and symptoms, including those affecting the kidneys and intestines.

Magnesium is a mineral that's important for the body to turn food into energy and for bone health.

If a person's magnesium levels are too high or too low, it may indicate health problems.

The magnesium test may also be recommended to investigate symptoms such as long-term diarrhoea, irregular heartbeat, general weakness, or when diabetes is not well controlled.

Related tests for levels of calcium and potassium may also be arranged.

The magnesium blood test may be carried out in a hospital, clinic, or GP's surgery.

The results will come back through the doctor who requested the test. Any treatment to correct the levels will depend on the underlying cause of the high or low magnesium readings.

WebMD Medical Reference

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