Not enough bananas
Potassium, the main cation in the cells, is often lost through perspiration, feces and urine (1). A deficit of potassium is called hypokalemia (1). Hypokalemia may occur simply due to inadequate dietary potassium intake, although it is more likely due to a case where there is excessive loss of potassium (1).
Various reasons can cause excessive loss of potassium such as vomiting, heavy sweating or chronic diarrhea (1). It can often result of laxative abuse or drugs such as diuretics (1). It is possible to develop hypokalemia due to inappropriate IV fluid (1).The signs of hypokalemia are weakness, muscle twitching and depressed neuromuscular reflexes (1).
1. Nowak TJ, Handford AG. Pathophysiology: Concepts and Applications for Health Professionals. New York: McGraw-Hill, 2004.