Potassium is one of the vital minerals that the body needs to be supplied in sufficient quantities on a regular basis. In the organism, potassium takes on crucial functions in the regulation of cell growth, blood pressure, neuromuscular activities, the so-called membrane potential and many other processes. In the worst case, a potassium deficiency can lead to fatal impairments of the heart function.
A basic distinction is made between intracellular and extracellular potassium concentrations in the organism. The normal intracellular concentration is approximately 150 millimoles per liter (mmol / l), the extracellular concentration is around four millimoles per liter. In the medical community, potassium deficiency is defined as an insufficient potassium concentration in the blood serum, i.e. the extracellular area. The technical term is hypokalaemia. This is achieved when the concentration falls below a value of 3.5 millimoles per liter.
Symptoms of potassium deficiency
Too low a potassium concentration in the organism can, according to the processes in which potassium is involved, cause a multitude of complaints. At first, those affected usually experience general exhaustion and listlessness, which is also linked to the fact that potassium has a decisive influence on nerve and muscle activity. A pronounced potassium deficiency can lead to paralysis of the muscles for the same reason. These usually manifest in the limbs, but sometimes also affect other muscles. The impairment of nerve activity due to the potassium deficiency also leads to a weakening or sometimes even a lack of reflexes.
Potassium deficiency is also often noticeable in the digestive tract. A typical consequence is constipation, which in turn brings with it further complaints such as stomach pressure, feelings of fullness, bloated stomach and pain during bowel movements. In the worst case, pronounced potassium deficiency can cause a so-called paralytic ileus. This form of intestinal obstruction is due to paralysis of the muscles, which are required for the transport of the intestinal contents. It is a potentially life-threatening event in which the sufferers suffer, among other things, massive abdominal pain and a bloated stomach.
The effects of potassium deficiency on heart function are particularly critical, not only because nerve and muscle activity is generally restricted, but also because potassium has a significant effect on the so-called repolarization of the ventricular tissue according to an action potential. In the case of potassium deficiency, this repolarization can no longer take place appropriately and, in the worst case, the heart chamber remains in systole or the affected person suffers cardiac arrest. Cardiac arrhythmia or stumbling, atrial fibrillation and ventricular fibrillation are also possible consequences of the lack of potassium. Potassium deficiency also leads to heart problems in patients with a pacemaker, since the potassium concentration has a significant influence on the voltage-controlled implants. If the potassium concentration is too low, the action potential of the pacemakers increases, which leads to rapid heartbeat (tachycardia), but usually does not cause as serious problems as potassium deficiency in a healthy heart.
Potassium is generally thought to have a hypotensive effect and a pronounced potassium deficiency is considered to be a possible cause of blood pressure derailments or a risk factor for high blood pressure. However, it is not only the potassium concentration that is crucial, but above all its interaction with the sodium concentration in the organism for the regulation of blood pressure.
There is also a close relationship between the potassium concentration and the acid-base balance. Potassium deficiency is therefore considered to be a possible cause of overacidification of the body, which in turn is associated with a variety of other complaints, especially in naturopathy.
Potassium deficiency is usually caused by an inadequate intake of the mineral through food, with an increased excretion of potassium due to excessive fluid loss. According to the recommendations of the German Society for Nutrition, adults should ingest 4,000 milligrams of potassium per day, for children and adolescents, depending on their age, 1,100 milligrams to 4,000 milligrams are recommended. Since the body excretes a relatively large amount of potassium with the urine, an insufficient potassium intake can quickly lead to a deficiency in the organism.
With increased fluid loss, for example due to diarrhea or vomiting, the deficiency sets in more quickly and can also occur if the recommended daily dose is observed, since significantly more potassium than normal is excreted. This also applies in a similar way to (performance) athletes who lose a lot of fluid when sweating and massively excrete potassium in this way. Certain diuretics (diuretics) and laxatives also result in increased potassium excretion, which can lead to a significant potassium deficiency if taken for a long time. Poisoning with barium can also be mentioned as a possible cause of undersupply.
Furthermore, the so-called Conn syndrome and Gitelman syndrome are known as diseases that are associated with a significant potassium deficiency. Conn's syndrome - also known as primary hyperaldosteronism - is due to an excessive release of the steroid hormone aldosterone, which in turn leads to increased potassium excretion and increased sodium absorption. Among other things, this leads to a significant increase in blood pressure, which can be accompanied by complaints such as headaches, nosebleeds, ringing in the ears, visual disturbances or even tightness in the chest and other complaints.
In the worst case, the disease leads to a so-called hypertensive crisis, which must be treated as a medical emergency. The causes of the so-called primary Conn syndrome are diseases of the adrenal cortex (usually an adenoma or ulcer) and genetic predispositions, which lead to an excessive release of the steroid hormone aldosterone. Cirrhosis of the liver can be the cause of secondary Conn syndrome, for example.
In Gitelman syndrome, too, those affected show pronounced hypokalaemia, the cause of which has not yet been fully elucidated. The extremely rare hereditary disease can also lead to symptoms such as muscle cramps or even paralysis and massive discomfort in the digestive tract as early as childhood. In addition to the potassium deficiency, those affected also suffer from a pronounced magnesium deficiency, which in turn can cause further complaints.
The possible cause of the potassium deficiency is also the regular consumption of large amounts of cola. The caffeine, glucose and fructose contained in the body excreted more potassium and a potassium deficiency quickly arose with daily consumption of more than two liters of cola, according to a study by Greek scientists from the University of Ioannina in 2009. As soon as the cola The consumption was reduced, but the potassium concentration in the test subject's organism usually returned to normal quickly, the researchers report.
A comprehensive blood test is used to determine the potassium deficiency. If Conn syndrome is suspected, the concentration of the steroid hormone aldosterone can also be determined. If this is elevated, the kidneys are then often examined using imaging methods such as computer tomography or magnetic resonance imaging in order to determine any diseases of the organ. Blood pressure measurements may also be appropriate as part of the diagnosis.
A detected potassium deficiency is usually countered with an increased potassium intake through food. Foods with a potassium content of 0.2 to one gram per 100 grams are considered to be rich in potassium. These include various mushrooms, potatoes, tomatoes, spinach, beans or even fruits such as apricots, bananas and dates. However, it should be noted that foods rich in potassium have a diuretic effect and are therefore not suitable for patients with impaired kidney function who regularly need dialysis. If it is not possible to compensate for the potassium concentration by changing the diet, potassium supplements can be used.
If massive cardiac complaints can be observed due to the lack of potassium, intensive care inpatient treatment is required, in which injections or infusions of potassium aspartate, potassium chloride or potassium malate are used to slowly adjust the potassium level in the blood serum. The rapid administration of high-dose preparations is counterproductive here, since a sudden increase in the potassium concentration in turn can lead to considerable health problems or even cardiac arrest.
Conn's syndrome is treated with medication with drugs that are said to reduce the release of the steroid hormone aldosterone. If an adenoma of the adrenal glands triggers increased hormone release, the affected adrenal gland is usually removed by surgery. In the case of the genetically determined variants, however, those affected only have the option of drug therapy. You must take permanent medication to regulate the release of aldosterone and, if necessary, additional medication to lower blood pressure.
Potassium deficiency in patients with Gitelman syndrome is usually also treated by taking potassium supplements, which, however, can only help to alleviate the symptoms. A cure for the hereditary disease is still not possible, so that the patients usually have to rely on appropriate medicines to balance the potassium level throughout their lives.
Author and source information
This text corresponds to the specifications of the medical literature, medical guidelines and current studies and has been checked by medical doctors.
Dipl. Geogr. Fabian Peters
- James L. Lewis, III: Hypokalaemia, MSD Manual, (accessed October 6, 2019), MSD
- Deutsche Herzstiftung: Cardiac arrhythmias: Potassium and magnesium deficiency can trigger or aggravate them, (accessed October 6, 2019), herzstiftung.de
- MDhealth: Potassium Deficiency Causes and Treatments, (accessed October 6, 2019), MD
- Christian Löser: Malnutrition and malnutrition, Thieme Verlag, 1st edition, 2010
- James L. Lewis: Overview of Potassium Concentration Disorders, MSD Manual, (accessed October 6, 2019), MSD
- German Nutrition Society V .: Reference values potassium, (accessed October 6, 2019), DGE
ICD codes for this disease: E87.6ICD codes are internationally valid encryption codes for medical diagnoses. You can find e.g. in doctor's letters or on disability certificates.