The Power of Potassium: How to Get Enough
Elisa Zied, MS, RD, CDN
It’s that unsung hero that has myriad functions in the body. Potassium helps balance fluid and mineral levels, supports muscle contraction (it helps the heart beat steadily), and transmits nerve impulses. It also helps blunt the blood pressure-raising effects of a high sodium diet, and may even help prevent future bone loss. While it may not inspire water-cooler conversation, potassium—a key mineral found most notably in leafy greens, fruits from vines, and root vegetables—truly deserves star status in our diets.
The problem is, most Americans fail to get enough. Less than 3 percent of us currently meet recommended intake levels. Average intake for adults 20 and older is an estimated 2,770 milligrams—only about 59 percent of what’s recommended.
So why do we pass on potassium? Our love affair with and over-reliance on convenience foods and beverages (including salty and baked snacks, and sugar-sweetened beverages) not to mention fast food and take out foods (like burgers, fries, and other high-calorie, nutrient poor fare) are definitely contributors. Our intake of fruits, vegetables, beans, and low fat dairy products—packed with potassium (not to mention other vitamins, minerals, and beneficial substances) — also tends to fall short of current dietary guidelines.
In 2004, the Institute of Medicine set Dietary Reference Intakes (DRIs) for potassium, expressed as Adequate Intake (AI) levels; these new levels were based on those shown to reduce blood pressure and salt sensitivity, and lower the risk of developing kidney stones. The AI for males and females aged 14 and older is 4,700 milligrams per day. AIs for others include the following:
- Infants, 0 to 6 months: 400 mg
- Infants, 7 to 12 months: 700 mg
- Children, 1 to 3 years: 3,000 mg
- Children, 4 to 8 years: 3,800 mg
- Children, 9 to 13 years: 4,600 mg
- Children, 14 and older: 4,700 mg
- Pregnancy, 14-50 years: 4,700 mg
- Lactation, 14-50 years: 5,100 mg
Although the Daily Value (DV) for potassium—3,500 milligrams—is still used on food labels, current AIs are a better benchmark for optimal potassium intake.
Too little potassium in the diet can disrupt acid/base balance in the body, contribute to bone loss and kidney stones, and increase high blood pressure risk; a deficiency can cause muscle cramps, weakness, confusion, and/or reduced appetite. If blood levels of potassium drop too quickly, that can cause heart problems and in some cases, be fatal.
Although it’s tough to take in too much potassium, excesses (especially from supplements) can cause cardiac arrest and possibly death; those with kidney problems and anyone with certain medical conditions who take potassium supplements are most at risk for high blood levels. Be sure to consult with a physician before taking potassium supplements.
Focusing on your overall dietary pattern—consuming a balanced, nutrient-rich diet with foods and beverages from all the key food groups as outlined by the Dietary Guidelines for Americans—is an important first step to not only increase your potassium intake, but meet all your nutrient needs. But knowing which foods pack in potassium can also help—here are some top picks:
- Fresh, dried, and canned and dried fruit picks including papaya (a summer favorite), bananas, plantains, dried fruit (dates, raisins, and plums), and canned pumpkin; look for dried or canned fruit made with no sugar added.
- Fresh, canned, or frozen vegetables; spinach, sweet or white potatoes, beet greens, mushrooms, bok choy, parsnips, and tomato products (paste, sauce, or pureed); look for canned products made with no added sugar.
- Beans (white, green soybeans, red kidney, pinto, refried); choose bagged varieties or canned varieties that contain little or no sodium and no added sugar often.
- Low fat milk and yogurt; look for no sugar added options.
- Fish: halibut, haddock, and sockeye salmon.
Do you eat enough potassium everyday?
Elisa Zied, MS, RD, CDN, is a nationally recognized registered dietitian and author of Nutrition At Your Fingertips, Feed Your Family Right!, and So What Can I Eat?!. She is also a national media spokesperson for the American Dietetic Association. For more information, go to www.elisazied.com, and www.nutritionatyourfingertips.com. Follow Elisa on Twitter and Elisa on Facebook.