Potassium (symbol K) is an essential macromineral in human nutrition and very important mineral for the proper function of all cells, tissues, and organs (heart, kidneys, etc.) in the human body. Potassium plays a crucial role in skeletal and smooth muscle contraction, which makes it important for normal muscular function . It is also important in maintaining fluid and electrolyte balance in the body.
Sources of Potassium
Most of the times people get sufficient potassium quantities from balanced diet (rich in vegetables and fruits). Foods rich in potassium include: bananas, avocados, parsley, dried apricots, chocolate, tomatoes, potatoes, salmon, chicken, and other meats.
Bannanas are a good soruce of potassium.
Potassium and Bodybuilding
When bodybuilders prepare themselves for competition they are often in a state of dehydration and during that phase they also cease to consume sodium and salt. One of the many side effects of sodium deficiency are cramps. In hope to prevent cramping bodybuilders supplement with another electrolyte, potassium. One other reason for potassium supplementation during pre-competition phase is due to the usage of diuretics. Many diuretics (sometimes called water pills) decrease potassium in the blood . Loop diuretics and thiazide diuretics, eliminate sodium and water from the body and have the side effect of also causing potassium loss in urine. . Therefore, supplemental potassium is required.
According to Sheldon G. Sheps from Mayo Clinic , spironolactone (Aldactone), eplerenone (Inspra) and triamterene (Dyrenium) are so-called potassium-sparing diuretics, which means they do not eliminate potassium from the body.
Low Potassium (Hypokalemia) Symptoms
Potassium is most often used to treat the symptoms of (hypokalemia) which include [1,2]:
- Stomach disturbances
- Muscle cramps
- Arrhythmias (abnormal EKG [electrocardiogram])
Hypokalemia can be life threatening and is rarely caused by a lack of potassium in the diet. It is usually caused by the body losing too much potassium in the urine or intestines .
Higher Dietary Potassium Intake may Reduce Stoke Risk
An Italian meta-analysis of prospective studies  has shown that higher dietary potassium intake is associated with lower rates of stroke. This supports the recommendation for higher consumption of potassium-rich foods to prevent vascular diseases. Beneficial effect of potassium ingestion may be due to its hypotensive effect  but because of its small effect  this can not explain reduced stroke risk. Other suggested mechanisms include inhibition of free radical formation by vascular cells , vascular smooth muscle proliferation .
Adverse health effects from consuming large quantities of dietary potassium may occur in those suffering from kidney diseases. Consuming potassium can cause side effects such as diarrhea, stomach irritation, and nausea . Muscle weakness, slowed heart rate, and abnormal heart rhythm may occur at higher doses . Potassium supplements may also be beneficial, but because of potential risks, use should be carefully monitored.
- Steven D. Ehrlich. University of Maryland Medical Center. Retrieved from http://umm.edu/ at 20. Avgust 2013
- Sheldon G. Sheps, M.D. “Diuretics: A cause of low K+?” Mayo Clinic Retrieved from http://www.mayoclinic.com/ at 21. Avgust 2013
D’Elia, Lanfranco, et al. “K Intake, Stroke, and Cardiovascular A Meta-Analysis of Prospective Studies.” Journal of the American College of Cardiology 57.10 (2011): 1210-1219.
Cappuccio, Francesco P., and Graham A. MacGregor. “Does potassium supplementation lower blood pressure? A meta-analysis of published trials.” Journal of hypertension 9.5 (1991): 465-473.
Tobian, L., et al. Journal of hypertension. Supplement: official journal of the International Society of Hypertension 2.3 (1984): S363.
McCabe, Richard D., et al. Hypertension 24.1 (1994): 77-82.
McCabe, Richard D., and David B. Young. “K inhibits cultured vascular smooth muscle cell proliferation.” American journal of hypertension 7.4 Pt 1 (1994): 346-350.