Clayton's Health Facts: Potassium

Clayton South, SPN (ISSA), is a recognized expert in the fitness industry with over 150 fitness and nutrition publications to his credit.


What are they and where do they come from?

Potassium (K) is a mineral that performs many functions in the body. Dietary sources of fiber include: tomatoes, citrus fruit, beans, vegetables, milk, bananas and watermelon.

What does it do and what scientific studies give evidence to support this?

Potassium is utilized by the autonomic nervous system. The autonomic nervous system (ANS) controls heart beat, brain functions, and other crucial physiological processes. Potassium has been shown to lower blood pressure and kidney stones1, as well as reducing the risk of stroke.2, 3 This reduction may be possible because of potassium's ability to regulate and lower blood pressure.4 Potassium plays a key role in the function of nerve firing [an involuntary physiologic response to stimuli], and the contraction of muscles.

Research has demonstrated that consuming potassium helps in the building of bones.5, 6 This would be consistent with evidence that demonstrates potassium's ability to reduce the potential for the onset of osteoporosis.7

Potassium may help reduce muscle soreness that results from training. Any deficiency in potassium levels may result in decreased strength, and the early onset of exercise induced fatigue. Potassium helps to regulate water balance and is also needed for the synthesis of dietary proteins.

For individuals using diuretics, supplemental potassium can help ensure adequate levels exist within the body for use in the above mentioned processes. Stable potassium levels are also associated with lower occurrences of type 2 diabetes.8

Who needs it and what are some symptoms of deficiency?

Everyone. Signs of deficiency include a weak and disease susceptible immune system, susceptibility to overtraining, and an increased need for supplemental glutamine.

Populations that may benefit most from the consumption of potassium include: diabetics, the overweight or obese, and athletes.

How much should be taken? Are there any side effects?

If you are currently supplementing with potassium, or are considering supplementing with potassium, pay careful attention to how much fruit you are eating daily. Fruit contains a high amount of potassium and if you are supplementing with potassium, overdose is a possibility. Taking too much potassium can result in an upset stomach, flatulence, abdominal pain, diarrhea, vomiting, and burping. An excessive amount of potassium can result in a heart attack.

Diabetics and persons with kidney failure should consult a qualified medical practitioner prior to the use of potassium supplements. Follow the directions as prescribed on the products label.

Where can I get it?

There are different brand names that manufacture supplemental potassium.


  1. Gurhan GC, Willett WC, Rimm EB, Stampfer MJ. A prospective study of dietary calcium and other nutrients and the risk of symptomatic kidney stones. N Engl J Med 1993; 328: 833-838.
  2. Iso H, Stampfer MJ, Manson JE, Rexrode K, Hennekens CH, Colditz GA, et al. Prospective study of calcium, potassium, and magnesium intake and risk of stroke in women. Stroke 1999; 30: 1772-1779.
  3. Tobian L. High-potassium diets markedly protect against stroke deaths and kidney disease in hypertensive rats: an echo from prehistoric days. J Hypertens 1986; 4(suppl 4): S67-S76.
  4. He FJ, MacGregor GA. Potassium intake and blood pressure. Am J Hypertens 1999; 12: 849-851.
  5. New SA, Bolton-Smith C, Crubb DA, Reid DM. Nutritional influences on bone mineral density: a cross-sectional study in premenopausal women. Am J Clin Nutr 1997; 65: 183-189.
  6. Sebastian A, Harris ST, Ottaway JH, Todd KM, Morris RC. Improved mineral balance and skeletal metabolism in postmenopausal women treated with potassium bicarbonate. N Engl J Med 1994; 330: 1776-1781.
  7. New SA, Robins SP, Campbell MK, Martin JC, Garton MK, Bolton-Smith C, et al. Dietary influences on bone mass and bone metabolism: further evidence of a positive link between fruit and vegetable consumption and bone health. Am J Clin Nutr 2000; 71: 142-151.
  8. Colditz GA, Manson JE, Stampfer MJ, Rosner B, Willett WC, Speizer FE. Diet and risk of clinical diabetes in women. Am J Clin Nutr 1992; 55: 1018-1023.