Potassium is a mineral that your body needs to work properly. It is indicated by the symbol K. The chemical symbol K comes from kalium. It is a type of electrolyte. It is the most important cation of the intracellular fluid (ICF) in the body. It works in conjunction with sodium to maintain electrolyte balance.n in blood the K concentration is 3.5-5 mEq/L and in cells it is 155 mEq/L. Slightest change in the extracellular potassium affects the extracellular : intracellular potassium ratio. This in turn affects the neural transmission, muscle contraction and vascular tone. Almost all of the dietary potassium is absorbed in a healthy person. Potassium is excreted through urine. Excretion increases when intake increases. Small amounts are excreted by feces, sweat and other secretions. Diarrhea causes a large loss of potassium through feces. Since kidneys play a very important role in excretion of potassium, when renal function is compromised more K is retained in the body and its concentration increases in the blood.
Potassium helps our body in varied ways. Being the major cation in the cell, it helps in maintaining the osmotic pressure and controls the entry of Na in the cells. It is a part of the Na/K pump and helps in electrolyte balance. It is present in ionized form, aids in regulating the hydrogen concentration in the bodily fluid and thus the acid base balance. It maintains the membrane potentials, the difference in concentration of K and Na across the membrane creates an electrochemical gradient i.e. membrane potential. Control and maintenance of membrane potential is vital for nerve impulse transmission, cardiac function and muscle concentration. Many studies have shown that potassium-rich diets can lower blood pressure. There is also a relation of potassium-rich diets with a significant lower risk of kidney stones. Both deficiency and excess results in disturbance.
It also regulates muscle activity along with Na and Ca ions, K creates electrochemical impulse and tightly regulates the nerve transmission and excitability. Thus, it plays a key role in contraction of smooth muscles (cardiac muscles) and skeletal muscle. It is important for all muscular functions including digestion. Cardiac functions, electrochemical impulses are dependent upon serum potassium concentration. Slight alterations cause changes in ECG. K is also required in the carbohydrate metabolism and protein synthesis.
The intake of potassium is important in pathological conditions like diarrhea, kidney problems, cardiac problems. It is found in both animal and plant foods. Rich sources include banana, oats, potato, sweet lime, orange, coconut, mackerel, tuna, salmon and roughly also found in fruits, pulses, vegetables. Discarding water used for soaking or boiling results in loss of potassium due to leaching out from foods.
Deficiency of potassium is referred to as hypokalemia. The serum potassium levels are seen to be <3.5 mmol/L. It can occur due to prolonged vomiting, use of diuretics, alcoholism, excessive use of laxatives, metabolic disturbances and renal disorders. Coffee can also increase potassium excretion in urine. Inadequate potassium intake may lead to cardiovascular disease, in particular stroke. Potassium deprivation increases urinary excretion of calcium.
Some of the common deficiency symptoms are muscle cramps, weakness, lack of energy, stomach disturbances (constipation, bloating and abdominal pain) Lack of appetite and mental apathy.
The other moderate deficiency without hypokalemia are elevated blood pressure, increased salt sensitivity, increased bone turnover and high urinary calcium excretion. The severe deficiency includes cardiac arrhythmia, abnormal ECG, irregular pulse rate, rapid heartbeat and muscle paralysis.
Toxicity is referred to as hyperkalemia, which may lead to cardiac arrest and symptoms of which may include tingling of hands and feet, muscle weakness, temporary paralysis,taking too many potassium supplements, kidney disease, prolonged disease, cocaine use, potassium-covering diuretics, chemotherapy, diabetes and severe burns . This condition is rare in people who eat balanced diets. Severe cases can lead to death. It is difficult for a healthy adult to overdose on potassium from foods. However, people with kidney problems, older adults, and those who take medications for blood pressure may need less potassium.
Potassium is an essential mineral and electrolyte involved in heart function, muscle contraction, and water balance. A high intake may help reduce high blood pressure, salt sensitivity, and the risk of stroke. Additionally, it may protect against osteoporosis and kidney stones.
This article is written and submitted to The E Today by Shrushti Mehta.
We thank her for her research and analysis and hope to see the awarenesses about health and nutrition being spread ahead to larger mass of our citizens.