Potassium DESCRIPTION: Potassium is essential in maintaining nerve and muscle function. FUNCTIONS 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. DEFICIENCY 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. Back to Top   REQUIREMENTS There is no EC C Recommended Daily Allowance for potassium. The British RNI (Reference Nutrient Intake) for adults is 3500mg. Back to Top   SUPPLEMENTAL USES 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. Back to Top   SAFETY 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. Back to Top   INTERACTIONS AND CONTRA-INDICATIONS 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 SOURCES - Sodium 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. REFERENCES: 1. Haris A and Radó 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. Back to Top   Related News Stories   Keeping Osteoporosis At Bay The buffering effect of essential minerals is illustrated. Back to Top