Potassium is an essential mineral in human nutrition
and is one of the body's three major electrolytes.
Potassium is the principal intracellular cation.
Approximately 98% of the body's potassium is in intracellular fluid.
Both supplementary and dietary potassium is more than
90% absorbed from the gastrointestinal tract.
Intake of potassium ranges from 1.56 - 4.68 g/day in
the United States. A dietary intake of about 3.5 gm of potassium is considered
to be a desirable intake of potassium for adults.
Potassium is lost from the body via urine and
gastrointestinal secretions. Minimal amounts are excreted in sweat.
The kidney has a major role in regulating potassium
balance.
Potassium and sodium work together to maintain osmolarity within cells.
Potassium, an extremely important electrolyte, functions in maintenance of:
Water balance and distribution via the
'sodium-potassium' pump
Acid-base balance
Muscle and nerve cell function
Energy production
Prevention and treatment of hypertension by
regulating normal blood pressure, maintaining proper calcium balance, and
minimizing the pressure-raising effects of a high sodium intake.
Potassium deficiency typically occurs as a result of
extended use of oral diuretics, severe diarrhea, hyperaldosteronism, diabetic
ketoacidosis or those on long-term TPN receiving inadequate potassium.
Estimated safe and adequate daily dietary intake of
potassium is 1.9 gm to 5.6 gm.1
Some causes of hyperkalemia include diminished renal potassium excretion, metabolic acidosis, hyperglycemia in the presence of insulin deficiency, moderately heavy exercise and digitalis intoxication.
Hyperkalemia familial periodic paralysis is a rare inherited disorder characterized by episodic hyperkalemia due to unexpected movement of potassium out of cells, usually precipitated by exercise.
Hyperkalemia from total body potassium excess is especially common when there is reduced urine excretion as in acute renal failure.
Hyperkalemia is uncommon in chronic renal failure until the glomerular filtration rate falls below 10-15 mL/min unless other sources of potassium load are present, such as diet.
Oral doses greater than 18 g of potassium taken at one time may lead to severe hyperkalemia in those with normal renal function.
Trimethoprim/sulfamethoxazole [Bactrimâ, Septraâ],
antimicrobial agents used to treat urinary tract infections, may increase
concentrations of potassium in the body. Symptoms of hyperkalemia include
irregular heart rhythm, muscle weakness, nausea, vomiting, and diarrhea.
People on long-term treatment with this antibiotic, should not take potassium
supplements except on advice of a physician or pharmacist. Besides potassium
supplements, other sources of potassium such as high-potassium diets and salt
substitutes containing potassium should be avoided.
Concurrent use of an ACE inhibitor and potassium may
result in elevated serum potassium concentrations. Monitoring serum potassium
concentration is necessary.
Potassium-sparing diuretics, such as amiloride
[Midamorâ] and triamterene [Dyreniumâ] that are used to treat edema, increase
potassium retention and can produce severe hyperkalemia. It is not advised to
increase the potassium intake except on the advice of a doctor or pharmacist.
Hypokalemia is sometimes seen in patients who take
digoxin [Lanoxinâ], a cardiac drug. Therefore, use caution before
discontinuation of a potassium preparation in these patients.
Cisplatin [Platinolâ] is a chemotherapeutic agent used with other drugs to treat various cancers. Cisplatin-induced kidney damage leads to the loss of minerals from the body, including potassium. Supplementation should be supervised by a physician or pharmacist.
Information on the relationship between substances and disease is provided for general information, in order to convey a balanced review of the scientific literature. In many cases the relationship between a substance and a disease is tentative and additional research is needed to confirm such a relationship.
Cardiovascular disease:
For the last 10 years, numerous studies have shown that proper intake of
minerals such as calcium, magnesium and potassium is a factor in maintaining
blood pressure in humans. 5
Ascherio and colleagues6 studied the effect of
potassium, magnesium, calcium, and fiber on stroke risk among men (n=
43,738)participating in the
Health Professionals Follow-Up Study. During 8 years of follow-up, the
findings suggested that consumption of a diet rich in potassium (top fifth of
potassium intake median of 4.3 g/day), magnesium and fiber (especially from
cereals) is protective against stroke mortality in men at all levels of blood
pressure, but particularly in hypertensive subjects.
Bone
Density: Tucker and
colleagues7 supported the hypothesis that alkaline-producing dietary
components, specifically potassium, magnesium, fruit and vegetables, may help
maintain bone mineral density (BMD). 1,164 subjects from the Framingham Heart
Study were investigated for associations between dietary components contributing
to alkaline environment and BMD in elderly subjects. Food frequency
questionnaires were used to evaluate nutrient intake. Four years of follow-up
showed that higher potassium intake was significantly associated with greater
BMD.
The dietary supplement information contained on this site has been compiled from published sources thought to be reliable, but it cannot be guaranteed. Efforts have been made to assure this information is accurate and current. However, some of this information may be purported or outdated due to ongoing research or discoveries. The authors, editors and publishers cannot accept responsibility for errors or omissions or for any consequences from applications of the information in this site and make no warranty, expressed or implied, with respect to the contents herein.
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