The Nutrition Source

Most Americans consume far too much sodium and far too little potassium, an eating pattern that puts them at higher risk of heart disease and death. (1) Making a few changes in food choices can help shift the balance. Potassium levels are naturally high in vegetables and fruits, and sodium levels are naturally low. Large amounts of sodium are often added to foods during processing. So choosing produce that is fresh or frozen, or choosing foods that have not had salt added in processing, can help curb dietary sodium and boost potassium.

Currently, Nutrition Facts labels are not required to list the potassium content of foods. But often foods that are highest in potassium are those that don’t carry a label: Good sources include vegetables and fruits, especially leafy green vegetables (spinach, collards, and the like), orange vegetables (sweet potato, winter squash), and citrus fruits (oranges and grapefruits), as well as dried beans. Canned beans can be quite a bit higher in sodium, so make sure to choose low-salt varieties.

Potatoes and milk are often cited as examples of potassium-rich foods. But it’s important to look at the whole food, not just a single nutrient: Potatoes do have good amount of potassium, yet they are also high in rapidly-digested carbohydrate—the scientific term for it is that they have a high “glycemic index” and “glycemic load.” Regularly eating potatoes and other high glycemic foods can make it hard to control weight and, over time, can increase the risk of diabetes and heart disease; that’s why the Healthy Eating Pyramid recommends using potatoes and similar foods sparingly. Milk, too, has a fair amount of potassium (366 milligrams per cup), but it also contains a fair amount of sodium (107 milligrams per cup); high intakes of dairy products are linked to an increased risk of prostate cancer in men, as well as to other health concerns, so it’s best to limit dairy to one to two servings a day and choose other food sources of potassium.

Switching from table salt to a potassium-based salt substitute is another way to shift your sodium-potassium balance, and some preliminary research suggests that making this switch may have benefits for the heart. (2) But these potassium-based salt substitutes are not for everyone: Extra potassium can be dangerous for people who have kidney disease  or who are taking medications that can increase potassium levels in the bloodstream. So check with your doctor before trying a potassium-based salt substitute. 

Sodium and Potassium Amounts in Fresh and Processed Foods

*Note: Values on fresh foods assume no added salt in cooking or at the table

Source: USDA National Nutrient Database for Standard Reference

References

1. Yang Q, Liu T, Kuklina EV, et al. Sodium and Potassium Intake and Mortality Among US Adults: Prospective Data From the Third National Health and Nutrition Examination Survey. Arch Intern Med. 2011;171:1183–91.

2. Chang HY, Hu YW, Yue CS, et al. Effect of potassium-enriched salt on cardiovascular mortality and medical expenses of elderly men. Am J Clin Nutr. 2006;83:1289–96.

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