Potassium is an essential mineral needed to regulate water balance, levels of acidity, blood pressure, and neuromuscular function. This
mineral also plays a critical role in the transmission of electrical impulses in the
Where is it found?
Most fruits are excellent sources of
potassium. Beans, milk, and
vegetables contain significant amounts of potassium.
Potassium has been used in
connection with the following conditions (refer to the individual
health concern for complete information):
Who is likely to be deficient?
So-called primitive diets provided much greater levels of potassium than modern diets,
which may provide too little. Gross deficiencies, however, are rare except in cases of
prolonged vomiting, diarrhea, or use of
drugs. People taking one of these drugs are often advised by their doctor to take
supplemental potassium. Prescription amounts of potassium provide more than the amounts sold
over the counter but not more than the amount found in several pieces of fruit.
How much is usually taken?
The best way to obtain extra potassium is to eat several pieces of fruit per day, as well as liberal amounts of vegetables. The amount of potassium found in the diet
ranges from about 2.5 grams to about 5.8 grams per day. The amount allowed in
supplements—99 mg per tablet or capsule—is very low, considering that one banana can contain 500 mg. One should not attempt to
achieve higher potassium levels by taking large numbers of potassium pills. This concentrated
form of potassium can irritate the stomach—a problem not encountered with the potassium
Are there any side effects or interactions?
High potassium intake (several hundred milligrams at one time in tablet form) can produce
stomach irritation. People using potassium-sparing drugs should avoid using potassium
chloride-containing products, such as Morton Salt Substitute®, No Salt®, Lite
Salt®, and others and should not take potassium supplements, except under the supervision
of a doctor. Even eating several pieces of
fruit each day can sometimes cause problems for people taking potassium-sparing drugs, due
to the high potassium content of fruit.
Potassium and sodium work together in the body to maintain muscle tone, blood pressure,
water balance, and other functions. Many researchers believe that part of the blood pressure problem caused by too much salt (which
contains sodium) is made worse by too little dietary potassium.
People with kidney failure should not take potassium supplements, except under careful
Are there any drug
Certain medicines may interact with potassium. Refer to drug interactions for a list of those medicines.