Potassium is an important electrolyte for our bodies. Its functions are alongside and balancing to sodium, another important electrolyte. Because potassium and sodium are connected functionally in the body, we look for proper balance of them in the diet, but dietary potassium isn’t something people think about much… besides maybe eating a banana during muscle cramps.
Potassium function
Our nerves being able to send signals, us being able to move our muscles, and our bodies conducting proper fluid balance, such as blood pressure regulation, are just a few of the major things we rely on both potassium and sodium for. Increasing potassium can help elevated blood pressure, or hypertension, but research shows that this is moreso for folks who have high blood pressure due to eating a diet high in sodium.
Potassium in the diet
In 2014, Jackson et al conducted the first national representation study of dietary sodium and potassium intake using 24-hour urine collections (instead of relying on wrought-with-error,-misrepresentation,-and-variable 24-hour diet recalls, as was previously the custom). They reported that the average sodium intake for a US adult was well over the federally recommended <2,300 mg of sodium/day, with a more specific reported average for hypertensive US adults around 3,746 mg/day. On the other hand, dietary potassium intake was well below the federally recommended 4,700 mg of potassium/day*, with a reported average of 1,997 mg of potassium/day.
*Adequate intake for potassium was updated in 2019 to 2,600 mg-3,400 mg for US adults.
This finding makes sense for standard US dietary patterns though. Very little of the dietary sodium we consume is naturally occurring in foods. Our dietary sodium is coming from us adding salt to the food we cook or the food that is served to us, or in processed/ultra-processed foods that we eat. Potassium on the other hand, isn’t getting added to foods… this is an electrolyte that is found in high amounts in naturally occurring foods. All of the highest potassium foods will be plant foods–many greens, legumes, and root vegetables contain between 500 and 1,000 mg per serving. Fruits (e.g., bananas) can contain up to 500 mg per serving, but many other fruits are well below this amount. Among animal foods, seafood items tend to have more potassium than land animal meats. This simplifies (or does it make incredibly more difficult) the method of decreasing sodium while increasing potassium in the diet: prioritize naturally occurring foods (unprocessed or minimally processed), control the amount of salt that you add to your own cooking or cooking that is served to you, and minimize processed and ultra-processed foods in the diet as much as possible. (By the way, if you’re looking to read more about the seemingly arbitrary labels of “minimally processed”, “processed”, and “ultra-processed”, check out our most recent blog!: https://www.atlanticnaturopathic.com/post/what-are-processed-foods)
Here are some common foods with their potassium content (mg) listed:
Food Item | Potassium (mg) |
Fruit | |
Apricots, dried, 1/2 cup | 755 |
Prunes, dried, 1/2 cup | 635 |
Banana, 1 medium | 422 |
Orange, 1 medium | 237 |
Cantaloupe, cubed, 1/2 cup | 214 |
Apple with skin, 1 medium | 195 |
Vegetable | |
Acorn Squash, mashed, 1 cup | 644 |
Potato, baked, flesh only, 1 medium | 610 |
Sweet potato, 1 baked | 540 |
Spinach, raw, 2 cups | 334 |
Tomato, raw, 1 medium | 292 |
Broccoli, cooked, chopped, 1/2 cup | 229 |
Asparagus, cooked, 1/2 cup | 202 |
Kale, cooked, 1/2 cup | 150 |
Lettuce, iceberg, shredded, 1 cup | 102 |
Nuts, seeds, legumes | |
Lentils, cooked, 1 cup | 731 |
Kidney beans, canned, 1 cup | 607 |
Soybeans, mature seeds, boiled, 1/2 cup | 443 |
Cashew nuts, 1 ounce | 187 |
Peanut butter, 1 tablespoon | 90 |
Flaxseed, whole, 1 tablespoon | 84 |
Dairy and dairy alternative products | |
Milk, 1%, 1 cup | 366 |
Yogurt, fruit variety, nonfat, 6 ounces | 330 |
Soymilk, 1 cup | 287 |
Yogurt, Greek plain nonfat, 6 ounces | 240 |
Mozzarella cheese, part skin, 1.5 ounces | 36 |
Animal proteins | |
Pork tenderloin, 3 ounces | 370 |
Chicken breast, boneless, grilled, 3 ounces | 326 |
Salmon, Atlantic, farmed, cooked, 3 ounces | 326 |
Beef, top sirloin, grilled, 3 ounces | 315 |
Turkey breast, roasted, 3 ounces | 212 |
Tuna, light, canned in water, drained, 3 ounces | 153 |
Potassium supplementation
What about just supplementing with potassium? Overall, supplemental potassium is reserved for specific conditions like calcium oxalate kidney stones, postural hypotension in elderly adults, and bone mineral density support. Supplemental or high intake of potassium can cause uncomfortable and even severe or life-threatening side effects, so focusing on increasing dietary intake of potassium is the sensible and safer way of approaching this electrolyte. Supplemental or even prescriptive potassium is something that should be managed by a doctor.
Main takeaways
US adults consume well over the federally recommended limit of <2,300 mg of sodium/day, but well under the federally recommended minimum of 4,700 mg of potassium/day.
Diets high in sodium can cause high blood pressure, and increasing potassium in those diets can help lower blood pressure.
Regardless of blood pressure status, it is safe to say that all US residents could benefit from decreasing dietary sodium and increasing dietary potassium.
Written by: Olivia Froehlich, N.D.
References:
Jackson, S. L., Cogswell, M. E., Zhao, L., Terry, A. L., Wang, C. Y., Wright, J., Coleman King, S. M., Bowman, B., Chen, T. C., Merritt, R., & Loria, C. M. (2018). Association Between Urinary Sodium and Potassium Excretion and Blood Pressure Among Adults in the United States: National Health and Nutrition Examination Survey, 2014. Circulation, 137(3), 237–246. https://doi.org/10.1161/CIRCULATIONAHA.117.029193
Whelton P. K. (2018). Sodium and Potassium Intake in US Adults. Circulation, 137(3), 247–249. https://doi.org/10.1161/CIRCULATIONAHA.117.031371