Potassium is the third most abundant mineral in the body and is classified as an electrolyte; 98 per cent of the body's potassium is intracellular. The mineral can be used to treat high blood pressure and strokes. Excess consumption of potassium can lead to kidney failure.
Potassium is vital in metabolism, transmission of nerve signals, muscle contraction, fluid balance and other cellular activities, making it a necessary component of an individual's everyday diet.
All meats, poultry and fish are sources of potassium. Some fruits and vegetables are high in potassium, including citrus fruits, raisins, prunes, apricots, bananas, melon, sweet potatoes (especially the skin), white potatoes, spinach, greens and squash. Other sources are white and pinto beans, low-fat milk and yoghurt.
No recommended daily allowance (RDA) of potassium exists for adults. A healthy individual is encouraged to consume approximately 3,500 to 4,700 mg (0.00012 to 0.00016 oz) of potassium per day, though more is recommended for pregnant women. Although no upper limit has been established, an excess of potassium may lead to toxicity.
Side-effects and cautions
The kidneys normally remove excess potassium from the body. Too much potassium may create a build-up of the mineral in the bloodstream (hyperkalemia) and poor kidney functioning. Hyperkalemia can cause nausea, fatigue, muscle weakness, numbness or irregular heartbeat. Thus, individuals with damaged kidneys should limit their intake of potassium. Hyperkalemia is treatable and is fairly common, seen in approximately 8 per cent of hospitalised patients.
To avoid overconsumption of potassium, limit dietary intake of fruits, vegetables and dairy, which are generally high in potassium. Use primarily herbs and spices that are deficient in potassium. Avoid salt substitutes (many contain potassium) and consume low-potassium foods such as green beans, cucumbers, raw cabbage, apple sauce and cranberries.