What does it do?
The quieter partner of the more talked about sodium, potassium plays a key role in maintaining the right balance of fluid and other vital substances inside and outside cells. Put very simply, the sodium-potassium pump is a nifty little mechanism that allows sodium and potassium to move in and out of cells in the correct amounts. It’s therefore important for giving our cells volume, but also for nerve transmission and normal muscle contraction (especially when it comes to the heart).
What’s the story?
Discovered in 1807, the name potassium is from the English word ‘potash’, originally meaning an alkali extracted with water in a pot of ash of burned wood, or tree leaves. So there you go.
Although it’s hard to have too much potassium, an excess can lead to hyperkalaemia, which can cause serious heart problems. Nevertheless, each and every time I see the word ‘hyperkalaemia’ written down, my brain initially tells me it’s a disease you get from eating too much kale.
How much do I need?
Both adult men and women aged over 19 need 3,500 mg per day.
What are good sources?
Both milk and seafood contain good amounts of potassium, along with peanuts and green leafy veg – particularly spinach and watercress, but fruit is really where it’s at for potassium (a mineral after my own heart). Bananas, peaches, mango, passion fruit, figs, papaya and raisins are all high in potassium.
Any ideas for using those ingredients?
Baked figs with hazelnut crumble and yogurt/roast chicken with onions and raisins/walnut, raisin and banana bread/easy guacamole/orange, feta, pistachio and watercress salad
References
British Nutrition Foundation (2021) Nutrition Requirements. Available here.
Martyn, K. (2011) Nutrition: made incredibly easy. London, Lippincott Williams & Wilkins, chp. 6.
The Royal Society of Chemistry (2017). Periodic Table, Potassium. Available here [accessed 6th July 2017].