What is potassium?

Potassium is an essential mineral and electrolyte that plays a central role in fluid balance, muscle function, nerve conduction, and heart health. It is the counterion to sodium and ensures that the distribution of fluid between the cells and the blood remains balanced.

Approximately 98% of potassium is found inside the body's cells, where it is crucial for the electrical stability of cell membranes. Particularly high concentrations are found in the muscles, liver, heart, and kidneys.

Since the body cannot store potassium, it must be obtained regularly through the diet - especially from plant-based foods such as fruit, vegetables, and legumes.

How does potassium work in the body?

1. Regulation of fluid balance:
Potassium and sodium work closely together to control the distribution of water between cells and the blood. While sodium binds water in the extracellular space (outside the cells), potassium draws water into the cells. This balance is crucial for stable cell function.

2. Nerve conduction and muscle function:
Potassium is necessary for transmitting electrical impulses along the nerves and muscles. Without sufficient potassium, the muscles - including the heart muscle - could not contract properly. A potassium deficiency can therefore lead to muscle weakness, cramps, or cardiac arrhythmias.

3. Cardiovascular system:
Potassium lowers blood pressure by promoting the excretion of sodium through the kidneys and relaxing the blood vessels. A potassium-rich diet is associated with a lower risk of high blood pressure, stroke, and heart disease.

4. Acid-base balance:
Potassium contributes to the neutralization of excess acids in the body and helps maintain the pH value within the physiological range.

5. Energy metabolism:
Potassium activates enzymes involved in carbohydrate metabolism and protein synthesis, thereby supporting energy production in cells.

Benefits of adequate potassium intake

  • Supports normal heart function

  • Regulates blood pressure

  • Promotes nerve and muscle function

  • Helps balance fluid and electrolyte levels

  • Supports energy production and cell regeneration

  • Contributes to a healthy acid-base balance

  • Protects against high blood pressure and stroke

Potassium-rich foods

Vegetables: spinach, broccoli, avocado, sweet potatoes, tomatoes, pumpkin
Fruit: bananas, apricots, oranges, kiwis, dates
Legumes: lentils, beans, peas
Nuts & seeds: almonds, pistachios, sunflower seeds
Whole-grain products & potatoes: particularly good sources of potassium

Recommended daily intake

According to the German Nutrition Society (DGE):

  • Adults: 4000 mg of potassium per day

  • Adolescents, pregnant women, and breastfeeding women: somewhat higher requirements

A balanced, plant-based meal plan usually meets this need without difficulty.

Potassium-to-sodium ratio

A healthy balance between potassium and sodium is crucial for blood pressure and cell function.

  • Ideally, the ratio should be at least 2:1 in favor of potassium.

  • In the Western diet, this ratio is often reversed because highly processed foods are very high in sodium but low in potassium.

Deficiency symptoms (hypokalemia)

Potassium deficiency can result from heavy sweating, diarrhea, vomiting, diuretics (water pills)or an unbalanced diet.
Typical symptoms:

  • Muscle weakness or cramps

  • Cardiac arrhythmias

  • Fatigue, irritability

  • Constipation

  • Low blood pressure

Severe potassium deficiency can be life-threatening and must be treated medically.

Overdose (hyperkalemia)

Excessive potassium intake through food is hardly possible for healthy people, as excess potassium is excreted through the kidneys.
It becomes dangerous in cases of impaired kidney function or excessive intake of potassium supplements - this can lead to cardiac arrhythmias or cardiac arrest.

Conclusion

Potassium is an essential mineral for the heart, muscles, nerves, and fluid balance. It helps regulate blood pressure, supports cell function, and protects the cardiovascular system. A potassium-rich diet with plenty of fruit, vegetables, legumes, and minimally processed foods ensures an optimal balance between sodium and potassium - the foundation for health, performance, and vitality.

Sources

  1. German Nutrition Society (DGE). (2020): Potassium - Reference values for nutrient intake.

  2. WHO (World Health Organization). (2012): Guideline: Potassium intake for adults and children.

  3. Aburto NJ, et al. (2013): Effect of increased potassium intake on cardiovascular risk factors and disease. BMJ, 346, f1378.

  4. He FJ, MacGregor GA. (2008): Beneficial effects of potassium on human health. Physiol Plant, 133(4), 725–735.