New Food Label Spotlight: Potassium on your plate

Ask anyone at your next workshop to name a food that’s high in potassium and they’ll likely say, “Bananas”. Why is it that bananas get all the credit for this important nutrient? You’ll be surprised to know that several other foods contain more potassium than bananas. This week we’ll explore why potassium is the next hot nutrient to be included on the new food label.

Potassium is actually a metal that is very light in nature. Plants and animals require potassium to survive and when levels drop too low or become elevated for any reason, they wreak havoc on the system. Right now, potassium is a voluntary nutrient on the nutrition facts label unless a nutrition claim has been made about it on the product’s package.¹

The role of potassium in our bodies is complex. Potassium resides in all cells and is necessary for normal cell function. Its role in keeping intracellular fluid volume and electrical signals that impact our nervous and cardiovascular system require a delicate balance. The majority of potassium in our bodies is intracellular with a smaller amount living in extracellular fluid. Because the intracellular concentration is 30 times higher than the extracellular, the difference creates a transmembrane gradient in electrochemical charges between two points, also known as the sodium-potassium pump. This gradient is needed for nerve transmission, muscle contraction and normal kidney function.²Potassium is absorbed in the small intestine via passive diffusion and can drop dramatically when someone experiences diarrhea, vomiting, excessive sweating or a side effect of medication. It may become elevated due to kidney dysfunction, certain medications or excessive supplemental use. Potassium will be added to the new food label because of its role in blood pressure reduction. The FDA decided in 2016 that potassium was one of four nutrients that impact public health. A deficiency in potassium may raise the risk of chronic disease (hypertension). ²As mentioned above, there are other foods beyond bananas that contain potassium. An easy way to tell your clients to get more potassium in their diets is to include more green leafy vegetables such as kale, collard and mustard greens, spinach, Brussels sprouts and broccoli. Dark orange and red fruits and vegetables are also good sources of potassium and include sweet potatoes, acorn and butternut squash, cantaloupe, peaches, mango, watermelon, tomatoes and citrus fruit. Kiwi, potatoes and avocado are also good sources of potassium. ³Fruits and vegetables are not labeled, but other foods that require Nutrition Facts labels may contain potassium. Bran cereal, for example, is a source of potassium as are dried fruits such as apricots, dates, prunes and raisins. Yogurt, milk, beans and lentils also provide a decent dose of this important mineral. ³Potassium recommendations are provided by the experts at the National Academies of Science, Engineering and Medicine (NASEM) through the Dietary Reference Intakes. The values include the RDA, Adequate Intake (AI), Estimated Average Requirement (EAR) and Upper Tolerable Limit (UL). ⁴NASEM updated the requirement for potassium and sodium in 2019 but did not find enough data to support Estimated Average Requirement. Instead, AIs were determined for all ages using the highest median potassium intakes in healthy children and adults. For infants, breast milk and complementary foods are used for estimates of potassium. ⁴Most Americans consume about 2700 mg of potassium per day, which is well below the Institute of Medicine’s recommendation of 4700 mg per day. The addition of potassium on the Nutrition Facts label should make it easier for people to obtain enough of this vital nutrient in their diet. It will also simplify meal planning for those individuals requiring a potassium restriction, as in chronic kidney disease. ⁴Teaching activity idea: Make a treasure hunt in your classroom to find potassium. Could it be hidden in foods that are good sources of potassium and come with a food label? Or could it be hidden in fruits and vegetables that are good sources and do not come with a label? Hide photos and packages of many items that are good sources of potassium all around and have people find them. Have everyone guess what they would need to eat in a day to get to 4700 mg.Here is one example (food and mg of potassium):

• Baked potato with skin, 925
• 1 banana, 425
• 1 cup cooked beans, 400
• 2 cups of milk, 700
• 1/2 papaya, 390
• 1 cup orange juice, 470
• 1 pear, 200

References:

1. http://www.rsc.org/periodic-table/element/19/potassium
2. https://ods.od.nih.gov/factsheets/Potassium-HealthProfessional/
3. https://health.gov/dietaryguidelines/2015/guidelines/appendix-10/
4. https://www.esha.com/potassium-spotlight/

Submitted by Lisa Andrews, MEd, RD, LDDownload a potassium handout here.[shopify embed_type="collection" shop="nutrition-education-store.myshopify.com" product_handle="food-label-new-food-label-display"]