A balanced diet normally provides the body with sufficient quantities of magnesium. If someone has a magnesium deficiency, they do not have enough magnesium in their blood. Magnesium is a mineral that is important for the functioning of muscles and nerves, as well as for preserving bones and teeth.
At a glance
- Magnesium is important for muscle, nerve and bone metabolism.
- It is an essential mineral. This means that the body is unable to produce magnesium itself and must absorb it from food.
- A deficiency can occur as a result of a restrictive diet or due to diseases of the kidneys.
- Pregnant and breastfeeding women, athletes and people with certain pre-existing illnesses have an increased requirement for magnesium.
- Muscle cramps, a tingling sensation or numbness in the arms and legs are typical signs of a magnesium deficiency.
- Eating green vegetables, pulses (legumes) and wholegrain products regularly can prevent a magnesium deficiency.
Note: The information in this article cannot and should not replace a medical consultation and must not be used for self-diagnosis or treatment.
What is a magnesium deficiency?
Magnesium is a mineral that has some important functions in the body. For example, it is important for the functioning of the muscles and therefore also of the heart. Magnesium also plays a role in building bones and teeth and in regulating the body’s calcium and potassium levels.
Eating a balanced diet normally ensures that the body gets enough magnesium to meet its needs. The mineral is present in many plant-based foods. There are large quantities in nuts and oil seeds, green vegetables, pulses/legumes and whole grains.
If the level of magnesium in the blood drops below a certain value, doctors refer to this as hypomagnesemia or magnesium deficiency.
A magnesium deficiency needs to be treated in order to prevent damage to health. If a deficiency is diagnosed, supplements of the mineral can be taken in the form of tablets or infusions.
What are the symptoms of a magnesium deficiency?
A magnesium deficiency may go unnoticed for a long time. Often, symptoms only begin to appear once the deficiency has become pronounced. In most cases, the symptoms are ambiguous and could be attributed to other illnesses or conditions.
Signs of a magnesium deficiency include, for example, frequent muscle cramps in the calf muscles, as well as tingling sensations and numbness in the arms and legs. Body temperature may also drop, leading the patient to feel cold frequently.
Symptoms such as headache, heart palpitations, cardiac arrhythmias (irregular heartbeat) or digestive problems may also occur.
In addition, some people become listless and lethargic, lose interest in things and begin to show apathetic and passive behavior.
What causes a magnesium deficiency?
A magnesium deficiency occurs because a person absorbs too little or excretes too much of the mineral. The body has mechanisms that prevent too much magnesium from being excreted.
In a very small number of people, however, this regulation mechanism doesn’t work correctly due to a genetic defect – for example, in the case of Gitelman syndrome, a rare, inherited kidney disorder.
In most other cases, a magnesium deficiency occurs for a different reason, for example:
- eating a restrictive diet, as can occur with eating disorders or extreme weight-loss diets
- high levels of alcohol consumption
- an increased need for magnesium due to stress, sport or pregnancy
- severe diarrhea and frequent vomiting
Certain diseases may also have a negative impact on magnesium levels in the body. These include:
- chronic kidney diseases
- diabetes mellitus
- inflammation of the pancreas (pancreatitis)
- chronic bowel diseases, such as Crohn’s disease and ulcerative colitis
- thyroid diseases, such as under-active parathyroid glands
A magnesium deficiency may also occur following a kidney transplant or surgical procedures involving the small intestine. In addition, certain diuretic medication to promote urine production and some antibiotics used to treat bacterial infections can increase the risk of a magnesium deficiency.
How common is magnesium deficiency?
Around 2 percent of all people have too little magnesium in their blood.
Pregnant women, people with diabetes and those who consume large amounts of alcohol are much more likely than others to have a magnesium deficiency.
What are the potential effects of a magnesium deficiency?
A magnesium deficiency is often associated with a deficiency of calcium (hypocalcemia) and potassium (hypokalemia, also known as hypopotassemia). These deficiencies, in turn, affect bone density and heartbeat. Calcium is important for bone stability. If there is too little magnesium in the blood, this makes it harder for calcium to be stored in the bones. A very severe magnesium deficiency can also cause serious cardiac arrhythmias.
How can a magnesium deficiency be prevented?
Eating a varied and balanced diet normally ensures that the body gets all the magnesium it needs.
In the case of an increased magnesium requirement due to certain pre-existing diseases or life circumstances, intake of magnesium-rich foods can be increased. These include, for example:
- green vegetables like spinach
- pulses/legumes such as beans and peas
- wholegrain foods
- seeds such as poppy seeds or sesame seeds
How is a magnesium deficiency diagnosed?
A family doctor can diagnose a magnesium deficiency by taking a detailed patient history and performing a specific blood test.
If the patient is experiencing symptoms such as heart palpitations or skipped heartbeats, doctors can also check the functioning of the heart with an electrocardiogram (ECG).
How is a magnesium deficiency treated?
The treatment of a magnesium deficiency depends on its causes and on any possible pre-existing diseases the patient may have. If the deficiency is mild with few symptoms, it is usually sufficient to modify the diet to include more magnesium.
For example, it can help to cook meals using fresh produce. Vegetables should also be eaten every day. In addition, a handful of magnesium-rich nuts contains lots of unsaturated fatty acids, which have a positive effect on the metabolism. Oil seeds such as sunflower seeds or linseeds can be lightly sprinkled over muesli and salads.
A pronounced magnesium deficiency can be resolved within a short space of time by taking magnesium tablets. However, these should only be taken following consultation with a doctor because prescription-free food supplements from drugstores or pharmacies may not contain the correct dosage.
People with kidney diseases or other illnesses that cause a magnesium deficiency, as well as people with symptoms of a severe deficiency can have the mineral administered into the veins by means of an infusion.
- UpToDate (Internet). Hypomagnesemia: Evaluation and treatment. Wolters Kluwer 2021. Aufgerufen am 14.10.2021.
- UpToDate (Internet). Hypomagnesemia: Clinical manifestations of magnesium depletion. Wolters Kluwer 2021. Aufgerufen am 14.10.2021.
- UpToDate (Internet). Hypomagnesemia: Causes of hypomagnesemia. Wolters Kluwer 2021. Aufgerufen am 14.10.2021.
- Gragossian A, Bashir K, Friede R. Hypomagnesemia. [Updated 2021 Sep 6]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Aufgerufen am 14.10.2021.
- National Institute for Health and Care Excellence (Internet). Preventing recurrent hypomagnesaemia: oral magnesium glycerophosphate. Aufgerufen am 14.10.2021.
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