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Quest Vitamins LTD,
8 Venture Way,
Aston Science Park,
B7 4AP.

Tel: 0121 359 0056
Fax: 0121 359 0313
Registered in England No. 2530437



Potassium is essential in maintaining nerve and muscle function.


Potassium is an electrolyte mineral which means that it has a part in controlling the fluid level and acid/alkaline balance of the body and its billions of cells. Potassium is kept inside the cell and is counter-balanced by Sodium that remains outside the cell.

As well as maintaining fluid and acid/alkaline balance, potassium (with sodium is important in maintaining the electrical potential that is so vital to the transmission of nerve impulses and functioning of the muscles.


Potassium deficiency causes weakness of the muscles and adversely affects the heart, causing heart arrhythmias (irregular beats). Acute potassium loss may even cause cardiac arrest. Mental confusion and Depression can also result from potassium deficiency and there may be an inability to concentrate urine. However, deficiency is uncommon in normal situations, arising only from excessive blood loss, sweating or Diarrhoea.


There is no EC C Recommended Daily Allowance for potassium. The British RNI (Reference Nutrient Intake) for adults is 3500mg.


Potassium may be deficient in people who take certain diuretic medications, corticosteroids, colchicine, and haloperidol. Such individuals may need to take a potassium supplement. However, a doctor?s advice should be sought first. Not all diuretics deplete potassium and some may indeed encourage its retention within the body.

Athletes or manual workers can also lose significant amounts of potassium through sweat (2,3) and may benefit from a potassium supplement together with other minerals (such as Calcium, Magnesium, etc.).

Long term use of certain antibiotics (especially penicillin) may deplete potassium and make a supplement advisable.

For people in general good health and for whom the above situations do not apply, supplementation with potassium is not normally advised except as part of a full spectrum multivitamin and mineral tablet.

N.B. Most potassium supplements provide little potassium in comparison with the recommended daily requirement of 3500mg.


An intake of potassium above 17.6g daily has been shown to induce symptoms of potassium overload in some individuals. This level represents a threshold for acute toxicity.


Those with impaired kidney or heart function, untreated Addison?s disease or taking digitalis-type drugs should not take high-level potassium supplements without medical supervision.

If taking ACE inhibitors, avoid taking potassium without medical supervision.

FOOD SOURCES - Potassium

Food (mg/100g)
Instant coffee 3780
Potato crisps 1190
Raisins 860
Potatoes 360
Pork 360
Cauliflower 350
Tomatoes 290
Chicken 290
Bread, wholemeal 230
Peas, frozen 190
Streaky bacon 183
Oranges 180
Milk, whole 140
Eggs 136
Cheese, cheddar 120


Food (mg/100g)
Instant coffee 81
Potato crisps 550
Raisins 52
Potatoes 8
Pork 65
Cauliflower 8
Tomatoes 3
Chicken 75
Bread, wholemeal 560
Peas, frozen 3
Streaky bacon 1245
Oranges 2
Milk, whole 50
Eggs 140
Cheese, cheddar 610

The sodium contents are also given above so as to indicate which foods are most suitable for those on low sodium/high potassium diets. It is particularly of note that fruits and vegetables have very high potassium to sodium ratios.


1. Haris A and Rad? J. [Potassium - sparing diuretics (spironolactone, triamterene, amylorid)]. Orv Hetil, 137;35:1907-1914, 1996.
2. McKenna MJ et al. Effects of training on potassium, calcium and hydrogen. Iron regulation in skeletal muscle and blood during exercise .Acta Physiol Scand, 156;3:335-346, 1996.
3. Otukonyong EE and Oyebola DD. Electrolyte loss during exercise in apparently healthy Nigerians. Cent Afr J Med, 40;3:74-77, 1994.

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