Powerful Potassium: Sources, Guidelines and Cautions
Just about everyone knows that sodium can raise blood pressure, but fewer people know that potassium helps lower it. Unlike sodium, potassium is mostly found in very nutritious foods, so it's not surprising that a high-potassium diet has a host of beneficial cardiovascular effects. In fact, the higher the potassium level of your diet, the better your diet tends to be, period. That's why the new Dietary Guidelines for Americans emphasize potassium-rich foods.
Good news about potassium comes from an analysis in the Journal of the American College of Cardiology, which included data from 11 studies and 250,000 people. It found that an average increase of 1,540 milligrams of dietary potassium a day is linked to a 21 percent reduced risk of stroke. That works out to about three extra servings of high-potassium foods a day.
How much you need: The government recommends at least 4,700 milligrams of potassium a day—two or three times as much as sodium. The anti-hypertension DASH diet supplies about that much potassium. Most Americans get half that much.
Where to get potassium: Vegetables, fruits and beans are rich in potassium. Dairy products, fish and nuts are also good sources. These foods help keep us healthy in many ways. And by choosing more potassium-rich foods, you'll almost automatically cut down on sodium.
Who should be cautious: People who have impaired kidney function or are taking certain drugs may need to limit their potassium intake in order to prevent dangerous heart rhythm problems. This is especially true if you take hypertension medications that can increase potassium retention, such as ACE inhibitors and potassium-sparing diuretics. Don't take potassium supplements or use high-potassium salt substitutes, unless your doctor has recommended them.
Souces of Potassium
- Potato, baked, with skin, medium—925 mg
- Spinach, cooked, 1 cup—800 mg
- Avocado, cubed, 1 cup—730 mg
- Prune juice, 1 cup—710 mg
- Halibut or yellowfin tuna, cooked, 4 oz—600 mg
- White beans, canned, 1/2 cup—595 mg
- Yogurt, plain, 8 oz—580 mg
- Sweet potato, baked, with skin, medium—540 mg
- Orange juice, 1 cup—500 mg
- Brussels sprouts, cooked, 1 cup—495 mg
- Squash, winter, cooked, 1 cup—495 mg
- Lima beans, cooked, from dry, 1/2 cup—480 mg
- Broccoli, cooked, 1 cup—460 mg
- Cantaloupe, cubed, 1 cup—430 mg
- Tomatoes, chopped, 1 cup—430 mg
- Banana, medium—420 mg
- Carrots, chopped, 1 cup—410 mg
- Tomato sauce, 1/2 cup—405 mg
- Apricots, dried, 1/4 cup—380 mg
- Milk, nonfat, 1 cup—380 mg
- Corn, 1 cup—380 mg
- Lentils, cooked, 1/2 cup —365 mg
Source: Originally published in The University of California, Berkeley Wellness Letter (August 2011)