- Potassium is an essential Minerals macronutrient in human nutrition; it is the major cation (positive ion) inside animal cells, and it is thus important in maintaining fluid and electrolyte balance in the body.
- Fish such as salmon, cod, flounder, and sardines are good sources of potassium. Various other meats also contain potassium.
- Vegetables including Broccoli, Peas, lima beans, Tomatoes, Potatoes (especially their skins), and leafy green vegetables such as Spinach, Lettuce, and Parsley contain potassium.
- Fruits that contain significant sources of potassium are Citrus fruits, Apples, Bananas, and Apricots. Dried Apricots contain more potassium than fresh Apricots.
- Patients on dialysis for kidney failure should avoid excess consumption of these foods. These patients require specialized diets to avoid excess potassium in the blood (hyperkalemia).
What is potassium?
Potassium, Sodium and chloride comprise the electrolyte family of Minerals. Called electrolytes because they conduct Electricity when dissolved in Water, these Minerals work together closely. About 95% of the potassium in the body is stored within cells, while Sodium and chloride are predominantly located outside the cell.
Potassium is especially important in regulating the activity of muscles and nerves. The frequency and degree to which our muscles contract, and the degree to which our nerves become excitable, both depend heavily on the presence of potassium in the right amount.
 How it Functions
What is the function of potassium?
Muscle contraction and nerve transmission
Potassium plays an important role in muscle contraction and nerve transmission. Many of our muscle and nerve cells have specialized channels for moving potassium in and out of the cell. Sometimes potassium moves freely in and out, and sometimes a special Energy-driven pump is required. When the movement of potassium is blocked, or when potassium is deficient in the diet, activity of both muscles and nerves can become compromised.
Other roles for potassium
Potassium is involved in the storage of Carbohydrates for use by muscles as fuel. It is also important in maintaining the body's proper electrolyte and acid-base (pH) balance. Potassium may also counteract the increased urinary Calcium loss caused by the high-Salt diets typical of most Americans, thus helping to prevent bones from thinning out at a fast rate.
 Food Sources
What foods provide potassium?
 Deficiency Symptoms
Potassium occurs naturally in a wide variety of foods. As a result, dietary deficiency of potassium is uncommon. However, if you experience excessive fluid loss, through vomiting, Diarrhea or sweating, or if you take certain Medications (see section on Drug-Nutrient Interactions below), you may be at risk for potassium deficiency.
In addition, a diet that is high in sodium and low in potassium can negatively impact potassium status. While the typical American diet, which is high in Sodium-containing processed foods and low in fruits and vegetables, contains about two times more sodium than potassium, many health experts recommend taking in at least five times more potassium than sodium.
The symptoms of potassium deficiency include muscle weakness, confusion, irritability, fatigue, and heart disturbances. Athletes with low potassium stores may tire more easily during Exercise, as potassium deficiency causes a decrease in glycogen (the fuel used by exercising muscles) storage.
 Toxicity Symptoms
Elevated blood levels of potassium can be toxic, and may cause an irregular heartbeat or even heart attack. Under most circumstances, the body maintains blood levels of potassium within a tight range, so it is not usually possible to produce symptoms of toxicity through intake of potassium-containing foods and/or supplements.However, high intakes of potassium salts (potassium chloride and potassium bicarbonate) may cause nausea, vomiting, Diarrhea, and/or Ulcers.
In addition, the kidneys play an important role in eliminating excess potassium from the body, so if you suffer from kidney disease, you must severely limit your intake of potassium. To date, the National Academy of Sciences has not established a Tolerable Upper Intake Level (UL) for potassium.
 Impact of Cooking, Storage and Processing
Potassium losses from cooking of high-potassium foods can be significant. In the case of spinach for example, potassium levels have been shown to drop from 6.9 to 3.0 grams in 3 and 1/2 ounces of spinach after blanching for several minutes (a loss of about 56%).
Sometimes this passage of potassium out of foods can be nutritionally beneficial. For example, parsley tea often contains significant amounts of potassium because this mineral is leached out of the parsley leaves and into the hot tea Water.
 Health benefits of potassium
Potassium may be looked upon as an essential health nutrient, due to a number of health benefits of potassium:
Stroke: Potassium plays an important role in keeping the working of brain in normal state. It is of great importance in preventing the occurrence of stroke in human brain. It is a fact that a person suffering from this dreadful disease may be found deficient in this essential body nutrient.
Low blood sugar: Decrease in potassium level causes a drop in blood Sugar level. Decrease in blood sugar level causes sweating, headache, weakness, trembling and nervousness. Intake of potassium chloride and sodium provides immediate relief from such situation.
Muscle disorders: Potassium plays an important role in regular muscle contraction. Right concentration of potassium, is required for the regular contraction and relaxation of the muscle. Most of the potassium ions of the human body are present inside the muscle cells. It maintains muscle function and optimal nerve.
Brain function: Potassium channels play a key role in maintaining the electrical conductivity of brain and affect the brain function. It is also involved in higher brain function like memory and learning. In addition to it, serious ailments like epilepsy are related to the functioning of potassium channels.
Blood Pressure: Potassium is helpful in reversing the role of sodium in unbalancing the normal blood pressure. Thus, it acts as a vital component, which maintains the normality of blood pressure in human body. This further abolishes the possibilities of Heart diseases and hypertension. Regulation of blood pressure is an important function of this mineral.
Anxiety and Stress: Potassium is of great importance for people suffering from undesirable mental states like anxiety and stress. It is considered as a perfect stress buster and thus it ensures efficient mental performance of human body.
Muscular Strength: This is in fact, one of the most appreciable benefits of potassium, as it ensures proper growth of muscle tissues and proper utilization of energy released during metabolism to add significant worth to muscular strength. The muscles, together with cardiac muscle, are prone to paralysis due to deficiency of potassium in diet.
Metabolism: It assists in metabolic process of various nutrients like fats, proteins and Carbohydrates. Thus, potassium is of great value in extracting the energy out of nutrients consumed by man.
Heart and Kidney Disorders: The health benefits of potassium ensure good health for heart as well as kidneys. It plays an irreplaceable role in regulating the functions of potassium. Apart from this, this Minerals assists kidneys to remove waste by the process of excretion. However, it is strictly advisable to consult your doctor to get recommendations about dosage.
Water Balance: Potassium has another significant role to play in maintaining the desirable water balance in human body. There are different types of cells, which require having proper water balance for proper functioning and potassium aids these cells in regulating this balance.
Electrolyte: Potassium plays the significant role as an electrolyte in human body. It helps in regulating the level of fluids in human body and thus performs a number of critical body functions.
Nervous System: Potassium helps in boosting the spirit of nerve reflexes to transmit message from one body part to another. This in turn helps in muscle contraction to perform various activities every day.
Most potassium (95 %) goes into fertilizers and the rest goes mainly into making potassium hydroxide (KOH), by the electrolysis of potassium chloride solution, and then converting this to potassium carbonate (K2CO3). Potassium carbonate goes into glass manufacture, expecially the glass used to make televisions, while potassium hydroxide is used to make liquid soaps and detergents. A little potassium chloride goes into pharmaceuticals, medical drips and saline injections. Other potassium Salts are used in baking, photography and tanning leather, and to make iodize salts. In all cases it is the negative anion, not the potassium, which is the key to their use.
 Potassium in the Environment
Most potassium occurs in the Earth's crust as Minerals, such as feldspars and clays. Potassium is leached from these by weathering, which explains why there is quite a lot of this element in the sea (0.75 g/liter).
Minerals mined for their potassium are pinkish and sylvite, carnallite and alunite. The main mining area used to be Germany, which had a monopoly of potassium before the first World War. Today most potassium minerals come from Canada, USA and Chile. The world production of potassim ores is about 50 million tonnes, and reserves are vast (more than 10 billion tonnes).
Potassium is a key plant element. Although it is soluble in Water, little is lost from undisturbed soils because as it is released from dead plants and animal excrements, it quickly become strongly bound to clay particles, and it is retained ready to be readsorbed by the roots of other plants.
 Health effects of potassium
Potassium can be found in vegetables, fruit, Potatoes, meat, bread, Milk and nuts. It plays an important role in the physical fluid system of humans and it assists nerve functions. Potassium, as the ion K+, concnetrate inside cells, and 95% of the body's potassium is so located. When our kidneys are somehow malfunctioning an accumulation of potassium will consist. This can lead to disturbing heartbeats.
Potassium can effect you when breathed in. Inhalation of dust or mists can irritate the eyes, nose, throat, lungs with sneezing, coughing and sore throat. Higher exposures may cause a build up of fluid in the lungs, this can cause death. Skin and eye contact can cause severe burns leading to permanent damage.
 Environmental effects of potassium
Together with Nitrogen and Phosphorous, potassium is one of the essential Macrominerals for plant survival. Its presence is of great importance for Soil health, plant growth and animal nutrition. Its primary function in the plant is its role in the maintenance of osmotic pressure and cell size, thereby influencing photosynthesis and Energy production as well as stomatal opening and carbon dioxide supply, plant turgor and translocation of nutrients. As such, the element is required in relatively large proportions by the growing plant.
The consequences of low potassium levels are apparent in a variety of symptoms: restricted growth, reduced flowering, lower yields and lower quality produce.
High water soluble levels of potassium cause damage to germinating seedlings, inhibits the uptake of other Minerals and reduces the quality of the crop.