In brief
A mineral the body needs for nerves, muscles and the heart to work. It also reduces the effect of sodium on blood pressure.
- Only take a potassium supplement if your doctor prescribes one.
- Some salt substitutes contain potassium, so talk to your doctor before using them.
- Potassium levels are checked with a blood test.
How it works
Potassium lets nerves respond to stimulation and muscles contract, including the heart muscle, and it helps move nutrients into cells. The recommended intake is 3,800 mg a day for adult males and 2,800 mg for adult females.
Low potassium (hypokalaemia) is commonly caused by diuretic medicines and by dehydration from vomiting, diarrhoea or heavy sweating, and can cause weakness, tiredness, muscle cramps, constipation and abnormal heart rhythms. High potassium (hyperkalaemia) is most often caused by kidney disease or by medicines that reduce how much potassium the kidneys remove, and it is serious and potentially life-threatening.
Food sources
- Leafy green vegetables
- Starchy vegetables
- Dried fruits
- Tropical fruits
From the AskBioMap food guide:
Connections
6 connections on the map. Select a topic to read its page.
Potassium is needed for
Potassium lets nerves respond and muscles contract, including the heart muscle.
Potassium helps your nerves, muscles and heart to work.
Potassium can be raised by
Kidney disease is the most common cause of high potassium (hyperkalaemia), which can be life-threatening.
Potassium can lower
Potassium reduces the effect of sodium on blood pressure.
Sources: healthdirect Australia, Potassium; Better Health Channel (Victorian Government), Salt
Potassium is controlled by
The kidneys control electrolyte levels, and kidney disease is the most common cause of high potassium.
Sources: Pathology Tests Explained, Electrolytes; healthdirect Australia, Potassium
Potassium is measured by
The electrolytes blood test measures potassium along with sodium, chloride and bicarbonate.
Sources: Pathology Tests Explained, Electrolytes; healthdirect Australia, Potassium
Medicines and supplements
General education only. Never start, stop or change a medicine without your prescriber.
Sources
Each connection above names its own source. See every source AskBioMap uses.
Summarised from healthdirect. Sources read on 19 October 2026. General education only, not medical advice. Spotted a mistake? Please tell us through the HuBu-Intel contact page.