Potassium has been identified as a “shortfall nutrient” for which most individuals should strive to achieve higher intakes. There is a substantial body of evidence that suggests high potassium intakes can help decrease blood pressure in adults, which in turn may decrease the risk of stroke and coronary heart disease. There is also accumulating evidence to suggest that diets rich in potassium have a protective effect on age-related bone loss. Western diets have led to decreased potassium intakes and increased sodium intakes, because of the reduced consumption of fruits and vegetables. Low potassium to sodium intake ratios is more strongly related to cardiovascular disease than high sodium intake alone. Potatoes contain the highest amount of dietary potassium, however, other foods such as white beans, tomatoes, dates, bananas and low/non-fat yogurt are also good sources.
The Linus Pauling Micronutrient Information Center at Oregon State University has additional information regarding the health benefits of potassium.