Potassium is one of the electrolyte minerals. It is important in maintaining the body's acid-base and fluid balance. .
Potassium is abundant in the diet. It is found in most fruitsvegetablesdairy productsfishlean meatsgrainspoultry
Bananas, potatoes, avocados, cantaloupe and orange juice are especially good sources of potassium. Other good sources include apricots, orange juice, and cooked or dried beans and peas.
Potassium is found inside the cells, where it works with sodium, on the outside of the cells, to keep fluids balanced correctly. Working with sodium, potassium assists in the smooth working of muscles, such as the heart. This role is critical to basic heart function and blood pressure. Nerve impulses, that is signals, are transmitted using a mechanism whereby sodium and potassium flow past each other in and out of the cells.
A deficiency of potassium in the diet is unlikely and generally rare. Potassium deficiency can occur because of vomiting, diarrhea and long-term laxative and diuretic use. Low potassium levels can also be caused by chronic disease and the aging process. Kidney problems can cause a severe loss of potassium.
Common problems associated with low potassium levels include: weaknessappetite lossnauseafatiguehigh blood pressure or hypertensionirregular heart rhythms called cardiac arrhythmias
People taking medication for high blood pressure, such as diuretics, may need to take a potassium supplement. These individuals should consult their healthcare professionals. The body protects itself from potassium toxicity by dissolving and excreting the mineral. In severe cases, a person will vomit, to keep blood levels within safe limits.
When blood levels of potassium start to rise measurably, it is called hyperkalemia. This is usually due to a specific cause such as reduced kidney function, increased protein breakdown or severe infection. If excess potassium cannot be excreted, it can cause the heart to beat irregularly or stop.
People with kidney failure may not be able to excrete excess amounts. They may be put on a potassium-restricted diet. They need to be careful of salt-substitutes, because many of them contain potassium chloride, in contrast to regular salt, which is sodium chloride.
There is no Recommended Daily Allowance (RDA) for potassium. The minimum amount suggested for adults is 2,000 milligrams (mg) per day. Some experts suggest a level of about 3,500 mg per day to help protect against high blood pressure. The typical American adult gets between 800 mg and 1,500 mg per day. Following the Food Guide Pyramid should ensure a safe amount of daily potassium.
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Murray, M., ND. (1996). Encyclopedia of Nutritional Supplements. California: Prima Publishing.