Magnesium Test

This is a test done to evaluate magnesium level in the blood to determine the cause of abnormal levels of calcium and / or potassium. Magnesium is an electrolyte and any abnormality in its levels affects the electrolyte balance of the body.
Normally, the blood magnesium level is just about 1% of the total magnesium found in our body.
Magnesium forms a part of each body cell and is important for muscle contraction, nerve functions, energy production and maintenance of strong bones.
A large part of body’s magnesium combines with calcium and phosphorous to form bones. It is not unusual to have low calcium and potassium levels if the magnesium levels are low.
Sources of magnesium are green vegetables like spinach and dietary supplements.

Procedure and purpose of magnesium test

Blood sample is drawn by inserting a needle into a vein in the arm.

Magnesium levels in blood, cells and bone are maintained by how much get absorbed from the intestines and how much is excreted by the kidneys. The magnesium levels become imbalanced in conditions or diseases in which either there is excessive or decreased magnesium excretion from the kidneys or there is impaired absorption of magnesium by the intestines.
Therefore, level of magnesium in blood may be checked as a part of diagnosis or evaluation of seriousness of a kidney malfunction or gastrointestinal problems or of out-of-control diabetes.

If magnesium levels remain consistently low over a period of time, they result in low calcium and potassium levels and need to be checked as a part of diagnosis of disorders of conditions relating to calcium, phosphorous, potassium and / or parathyroid hormone.

Magnesium levels need to be checked regularly to monitor response to oral and intravenous magnesium supplements. Magnesium levels may also be recorded along with calcium and phosphorous tests to keep a check on body’s response to calcium supplements.

Magnesium test may be recommended if one suffers symptoms of abnormally low levels of magnesium. The symptoms include tiredness, muscle weakness, twitching and cramping, irritability, nausea, cardiac arrhythmia and seizures and / or diarrhoea.

Magnesium deficiencies are rarely diet-related, however, the doctor can ask you to get a magnesium test to indicate any deficiency in the evaluation of mal-absorption, diarrhoea, excess alcohol intake or malnutrition. Other reasons for getting the test done could be certain drugs and medicines which cause kidneys to excrete more magnesium. If one is required to take dietary supplements for magnesium and/or calcium, frequent tests need to be done to monitor the effects.

Test inference
Condition with low levels of magnesium in blood is called hypomagnesaemia signifies that
Magnesium is lacking in diet
Intestines are not properly absorbing magnesium
Kidneys are excreting excess of magnesium

Deficiencies can be attributed to below factors

• Low magnesium intake in diet (in older, malnourished or alcoholic people)
• Hypoparathyroidism (under-activity of parathyroid gland)
• Prolonged diarrhoea
• Uncontrolled diabetes
• Gastro-intestinal disorders (crohn’s disease)
• Severe burns
• Surgery
• Prolonged use of diuretics.

Rise in magnesium levels are mainly due to excessive supplementation or excretion problem and seldom due to dietary reasons. These reasons are

• Kidney malfunction
• Dehydration
• Hypothyroidism
• Hyperparathyroidism
• Intake of antacids or laxatives containing magnesium
• Addison’s disease
• Diabetic acidosis.