What is potassium good for?
Potassium is one of several essential minerals that your body needs in order to function correctly. It is actually the third most abundant mineral in the human body, after calcium and phosphorous.
Role as an electrolyte
Potassium, and also sodium, are of particular importance due to their roles as electrolytes, meaning that when they are dissolved in water, they produce positively charged ions, and it is this particular property that allows our nerves to conduct electrical impulses throughout the body. This is essential not only for heart function and other muscle contractions, but also several other bodily processes.
Nerve impulses are actually generated by sodium ions moving into cells and potassium ions moving out of cells. The movement of these ions changes the voltage of the cell, which triggers the corresponding nerve impulse.
Of course, this means that it is extremely important that we have an optimal amount of both potassium and sodium in our body. If we have either too much or too little potassium for example, this can affect our ability to properly generate nerve signals, resulting in weakened muscle contractions, an affected heartbeat, and potentially other health complications.
Role in hydration
Potassium also plays a fundamental role in our hydration. We all learned at school that the human body is roughly two thirds water, but approximately 40% of this water is actually found inside your cells, in a substance that is called intracellular fluid, or ICF. The other 60% is found outside your cells, such as in your blood, spinal fluid and between the cells. This is called extracellular fluid, or ECF.
The actual amount of water found in either ICF or ECF is determined by their concentration of electrolytes, especially potassium and sodium. Potassium is the primary electrolyte for the ICF, which means that it determines how much water is inside the cells, while sodium is the primary electrolyte for the ECF, and it determines how much water is outside the cells.
And that concludes today's biology lesson!
Aside from it's fundamental role in how our body operates, let's comment briefly on a few of the added health benefits of taking a decent amount of potassium.
Benefits for blood pressure
Research shows that a diet rich in potassium could potentially reduce blood pressure by facilitating the removal of excess sodium from the body, and we know that high levels of sodium can cause high blood pressure.
Reducing the risk of stroke
Many clinical studies have found that a potassium-rich diet is directly associated to a reduced risk of suffering a stroke, with several studies involving hundreds of thousands of participants showing that those who had the most potassium-rich diets showed up to a 24% reduction in the risk of suffering a stroke, together with a reduced risk of developing heart disease, when compared to those participants with the least amount of potassium in their diets.
Benefits for bone health
It has also been demonstrated that a potassium-rich diet can help prevent osteoporosis by reducing how much calcium is excreted in our urine. For example, a study in 62 middle-aged women found that participants who consumed the most potassium also had the greatest total bone mass. Another study of 994 healthy pre-menopausal women reached the same conclusion.
Potassium for kidney stones
On a related note, potassium's ability to reduce the amount of calcium that is excreted through our urine also means that it has the ability to reduce the risk of developing kidney stones, specifically when potassium is taken in the form of potassium citrate. Potassium citrate is one of the most popular formulations for potassium supplements, and fortunately this is the same form of potassium that is also found naturally in many fruits and vegetables.
When should I take potassium?
Potassium is best taken with a meal, and research suggests that taking it early in the day together with other supplements could offer the most benefits, so taking it with breakfast would be the ideal moment.
What are natural sources of potassium?
If you are interested in achieving your daily potassium intake through your diet, rich sources of potassium include:
- Avocados
- Sweet potatoes
- Potatoes
- Butternut squash
- Spinach
- Bananas
- Apricots
- Raisins
- Pomegranates
- Watermelons
- Oranges
Potassium data sources & further reading
Last updated by Asklepios on 30th January, 2025