Too much versus too little POTASSIUM (K)

Potassium is important for supporting the activity of the heart (it speeds up the heart rate) and indispensable for protein synthesis and thus for the growth process. Together with phosphorus it promotes the supply of oxygen to the brain, and the ratio between potassium and sodium has to be 1/0.7, otherwise disorders of the heart and the adrenal glands as well as spasmophilia occur. Potassium prevents the loss of calcium, keeps bone density within its parameters, has a diuretic effect, favours the excretion of water and sodium chloride, takes part in digestive processes, occurs in the composition of pancreatic and intestinal juice and increases neuromuscular excitability.

A lack of potassium often occurs together with appetite disorders and can be due to a weight-loss diet, an increased consumption of coffee or sweets, frequent use of laxatives or long-term use of steroids. The clinical symptoms are vomiting, thirst, nausea, irritability, restlessness, muscle weakness, cramps, tiredness, muscle pain, hypoglycaemia, acne, obesity, early senility and heart rhythm disorders.

An excess of potassium does not occur on a normal diet, but hyperkalaemia can be the result of kidney and adrenal disease, severe infections and muscle trauma. In this case the clinical signs are mental confusion, constipation, bloating, muscle weakness, low blood pressure and disturbances in the supply of oxygen to the lungs.

The main sources of potassium are vegetables and fruit. Large amounts are contained in beans, spinach, potatoes, mushrooms, all green leafy vegetables, tomatoes, sunflower and pumpkin seeds, citrus fruits, melons, pears, bananas, grapes, hazelnuts, almonds, dates, cocoa, chocolate and coconut . Animal products also contain potassium: eggs, meat, fish and dairy products. Alcoholic and sugary products are low in potassium or free of it.

The body loses potassium through the consumption of alcohol, tobacco, coffee, sugar and diuretics and during physical and mental strain. Treatments with prednisolone cause large losses of potassium and considerable retention of sodium in the body.