What is potassium?

Potassium is a mineral that is essential for all of the body's functions. It helps your nerves, muscles and heart function properly, as well as helping move nutrients and waste around your cells.

Read more on potassium and your health.

Where does potassium come from?

Potassium is found in a wide variety of plants, meats and drinks.

Potassium is also an ingredient used in some salt substitutes that people take to replace sodium in their diet. If you have kidney disease or take certain medicines, your potassium levels may be too high, so it is important to talk to your doctor before using a salt substitute.

How much potassium do I need?

The amount of potassium you need depends on your age, stage of life and whether you have any medical conditions.

Having too little or too much potassium in the body can affect your health. This rarely happens only due to your diet. Most healthy people get enough potassium (and not too much) through their diet alone.

Some health problems and medicines (such as diuretics) can cause people to have too little potassium in their body (hypokalaemia).

Some people are at risk of developing potassium levels that are too high. The most common causes of high potassium levels are kidney disease or taking medicines that decrease the amount of potassium the body removes via the kidneys. People with these risk factors may need to limit their dietary potassium intake.

If you're not sure, or if you think you may be at risk of abnormal potassium levels, talk to your doctor about getting a blood test.

What are the best sources of potassium?

Most people get enough potassium from a balanced diet.

There is plenty of potassium in:

• apricots and dried fruit
• tree fruits — such as avocados, apples, oranges and bananas
• leafy greens — such as spinach, kale and silverbeet
• vine fruits — such as tomatoes, cucumbers, zucchini, eggplant and pumpkin
• root vegetables — such as carrots, potatoes and sweet potatoes
• legumes — such as beans and peas
• milk, yoghurt, meat and chicken, as well as fish — such as halibut, tuna, cod, snapper

Should I take a potassium supplement?

If you take certain types of diuretic medicines, you may not get enough potassium from your diet. If you take diuretics, ask your doctor if you need your potassium levels checked.

Having too much potassium in your body can be dangerous, so only take a potassium supplement under medical advice.

Resources and support

• Kidney Australia has information about maintaining a healthy diet, if you have chronic kidney disease.
• Visit Nutrition Australia for information about healthy eating.
• Eat for Health has information and advice about healthy eating.