Potassium

Potassium

DEFINITION
Potassium is an essential mineral that is contained in every
body cell.
DESCRIPTION
Most of the Potassium in the body is found inside, rather than
outside, the cells. Potassium has a small, positive electric charge
and it helps to regulate the electrical activity in the cells,
which is important for transmitting impulses between nerves and
allowing muscles to contract. Potassium is also important for
controlling the fluid levels in the body as well as the acidity
(pH) of the body fluids. Potassium, together with sodium, helps to
regulate the blood pressure and is important for the proper
function of the heart and kidneys. Potassium is excreted mainly by
the kidneys through urination and through the skin by perspiration.
Potassium may play a role in reducing high blood pressure.
Prolonged diarrhoea, vomiting, sweating and the use of some
diuretics deplete the Potassium level. The Potassium in food is
easily destroyed if food is soaked or boiled. If the levels of
Potassium in the body are too high (Potassium toxicity), the heart
cannot work normally and there is a risk of death from cardiac
arrest (heart attack). Potassium is available in supplement form
and is often found in combination with other minerals e.g. calcium,
magnesium and potassium.
DEFICIENCY
Symptoms of Potassium deficiency include nervous disorders,
insomnia, hypertension (high blood pressure), constipation, a slow
and irregular heartbeat and muscle damage. People with diabetes are
often deficient in this mineral. Diuretics, fluid tablets and other
heart disease medications tend to deplete the body of Potassium.
Other symptoms of Potassium deficiency include muscle fatigue, poor
appetite, mental apathy and general tiredness.
SOURCES
The best food sources of Potassium are prunes, raisins,
tomatoes, bananas, vegetables, skim milk, beef and pork. Fresh
fruit juices also contain large amounts of Potassium.
DOSAGE
The recommended dietary intake (RDI) for Potassium is 1950 to
5460 mg (50 to 140 mmol) per day for adults. People with high blood
pressure who are taking diuretic medications may be advised by
their Doctor to eat Potassium-rich foods or take Potassium
supplements. This is because diuretic drugs increase the amount of
Potassium that is lost from the body.