What is potassium?

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

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

Since the body cannot store potassium, it must be regularly ingested through food – primarily through plant-based foods such as fruits, vegetables and legumes.

How does potassium work in the body?

1. Regulation of fluid balance:
Potassium and sodium work closely together to regulate 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 the transmission of electrical impulses along nerves and muscles. Without sufficient potassium, muscles—including the heart muscle —could not contract properly. A potassium deficiency can therefore lead to muscle weakness, cramps, or heart rhythm disturbances .

3. Cardiovascular system:
Potassium has a blood pressure-lowering effect because it promotes the excretion of sodium via the kidneys and relaxes 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 to maintain the pH level within the physiological range.

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

Benefits of adequate potassium intake

  • Supports normal heart function

  • Regulates blood pressure

  • Promotes nerve and muscle function

  • Helps to 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 potassium per day

  • Adolescents, pregnant women and breastfeeding mothers: slightly higher need

A balanced, plant-based diet usually covers this need without any problems.

Potassium and sodium ratio

A healthy ratio 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, as highly processed foods are very high in sodium but low in potassium.

Deficiency symptoms (hypokalemia)

A potassium deficiency can be caused by excessive sweating, diarrhea, vomiting, diuretics (water pills) or a one-sided 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 via 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, strengthens cell function, and protects the cardiovascular system. A potassium-rich diet with plenty of fruits, 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. Hey FJ, MacGregor GA. (2008): Beneficial effects of potassium on human health. Physiol Plant , 133(4), 725–735.