Why You Need Plenty of Potassium

Consumer Reports has no financial relationship with advertisers on this site.

When it comes to ­dietary strategies to control blood pressure, sodium gets all the atten­tion. But too little potassium could be just as important as too much salt.

“When you get enough potassium, it helps your body excrete sodium,” says Angie ­Murad, R.D., a nutritionist at the Mayo Clinic Healthy Living Program. “That eases tension in the blood vessel walls, which can help lower blood pressure.”

The mineral also helps blood vessels ­relax inde­pen­dent of the role it plays in sodium balance.

How Much Potassium Do You Need?

The recommended daily dose of potassium is 4,700 mg. But according to a study in The American Journal of Clinical Nutrition, less than 2 percent of Americans consume that much. The Dietary Guidelines Advisory Committee highlighted the lack of potassium in our diets by designating it a “shortfall nutrient.”

So should you take potassium supplements? Not unless your doctor tells you to. A very high intake of the mineral—which is easier to get with supplements than with food—may limit the kidney's ability to eliminate potassium, and that can lead to abnormal heart rhythms. The elderly as well as people with kidney disease or type 2 diabetes, and those who take certain medications (such as ACE inhibitors, beta blockers, and nonsteroidal anti-inflammatories) are most at risk. In addition, the type of potassium found in supplements is actually a different form than the kind that naturally occurs in food and may not provide the same benefits.

Where to Find Potassium

Swiss chard, 1 cup cooked: 961 mg

Acorn squash, 1 cup cubed: 896 mg

Spinach, 1 cup cooked: 839 mg

Baked potato, 1 small w/skin: 738 mg

Lentils, 1 cup cooked: 731 mg

Tempeh, 1 cup: 684 mg

Salmon, 5 ounces: 676 mg

White beans, ½ cup: 502 mg

Yogurt low-fat plain, 1 cup: 531 mg

Sun-dried tomatoes, ¼ cup: 463 mg

Cantaloupe, 1 cup cubed: 427 mg

Banana, 1 medium: 422 mg

Carrots, 1 cup cooked: 367 mg

Crushed canned tomato, ½ cup: 355 mg

Sweet potato, 1 medium w/o skin: 347 mg

Avocado, ½: 345 mg

Raisins, 1 small box (1.5 oz): 322 mg

Quinoa, 1 cup cooked: 318 mg

Pistachios, ¼ cup kernels: 310 mg 

Prunes, 4 whole pitted: 278 mg

Oranges, 1 cup slices: 274 mg

Apricots, dried, 6 halves: 244 mg

Editor's Note: This article also appeared in the September 2017 issue of Consumer Reports on Health.



More from Consumer Reports:
Top pick tires for 2016
Best used cars for $25,000 and less
7 best mattresses for couples

Consumer Reports is an independent, nonprofit organization that works side by side with consumers to create a fairer, safer, and healthier world. CR does not endorse products or services, and does not accept advertising. Copyright © 2017, Consumer Reports, Inc.