Vital for fluid balance and reducing high blood pressure.

Good food sources include tomato products, orange juice and dates. Deficiencies are commonly associated with a high salt intake. Diarrhoea and prolonged sweating also deplete levels.

RDA of potassium is 3,500mg.

Avoid supplements in old age due to declining kidney function. High doses can also cause vomiting, nausea and abdominal pain.