Potassium is one of a special group of minerals called electrolytes which includes calcium, magnesium, sodium and phosphorous. Electrolytes occur in the blood in an ionic form, meaning they carry an electric charge and are not attached to anything. Electrolytes affect the acidity of the blood (pH), the amount of water in the blood (and therefore blood pressure), and muscle function (including the heart). Potassium is essential for bone growth, proper nerve transmission, heart and kidney function, and adrenal function.
The role of potassium in regulating blood pressure is often overlooked. Potassium deficiency is at least as important, and possibly more so, than excess sodium (see my column #129 Salt in Balance, 29 August 2011). Other signs of potassium deficiency include:
• water retention
• muscle weakness and cramps
• heart arrhythmia
Our diets are often deficient in potassium. The Paleolithic diet was estimated to contain 11,000 mg potassium and 700 mg sodium. Compare that with our modern diet with 2,500 mg potassium and over 4,000 mg sodium. (Not that the Paleolithic diet ratio was necessarily ideal; the point here is that the ratio has flipped). The Health Canada “Adequate Intake” amount for potassium is 4,700 mg for adults.
Good dietary sources of potassium include vegetables like lima beans, squash, spinach, broccoli, sweet potatoes, avocados and asparagus, and fruits including papaya, prunes, cantaloupe and bananas. Don’t overdo the bananas, though, as they are high in sugar and have only half the potassium of the green vegetables. Unrefined sea salts with a pink color are another source of potassium. Potassium is also available as a supplement, usually in citrate form.
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.
Mercola: The Guilty Pleasure that Could Save you From Heart Disease, 5 March 2012
"Paleolithic Nutrition – A Consideration of Its Nature and Current Implications", New England Journal of Medicine, January 31, 1985: 312; 283-289, S. Boyd Eaton, M.D. and Melvin Konner, Ph.D.