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A Healing Nutrient Profile: Potassium

Nov 9 2020
4 min read
Close-up of hands chopping a banana with a knife on a wooden cutting board.

The mineral potassium is also a type of electrolyte, and is one of the major nutrients involved in...

...maintaining the proper electrical charge in the body. The flow of potassium and sodium in and out of cells supports the normal functioning of the heart, brain, kidney, and skeletal muscles. Without potassium it would be impossible for your body to maintain a regular heartbeat or properly transmit nerve signals to muscles so they can contract. A high-potassium diet offsets some of the harmful effects of too much salt (sodium) on blood pressure, and it seems to be protective against deaths from high blood pressure and stroke. Potassium is also vital for maintaining the balance of water in the body.

How Much Potassium Do You Need?

There’s no recommended daily allowance (RDA) for potassium. To keep blood pressure in check, lessen the risk of kidney stones, and reduce bone loss, aim for 4.7 grams (4,700 milligrams) daily of potassium through food, and 5.1 grams if you’re breastfeeding.

You lose potassium when you sweat. And if you’re vomiting or dealing with diarrhea, beware; both can cause rapid loss of the nutrient.

Potassium depletion can lead to fatigue, overall weakness, confusion, and muscle pains or cramps. If your urine is dark yellow, you have lost too much fluid and electrolytes; replenishing them with water is often sufficient, but if you’re especially depleted from exercise or illness you can also try an electrolyte drink. Look for varieties sold in health food stores, which tend to have fewer chemicals than mainstream brands.

Certain medications such as diuretics, cortisone drugs, and digitalis can also cause you to lose potassium, so your doctor may suggest that you take supplements along with your prescription. Supplements can produce gastrointestinal discomfort and a buildup of toxic levels of potassium in the blood, which can cause irregular heartbeats, so it’s best to only take them with a doctor’s approval.

What Are Good Sources of Potassium?

Bananas are famous for containing lots of potassium, but many fruits and vegetables — especially leafy greens, vine fruits (like tomatoes, cucumbers, and zucchini), root vegetables, and citrus fruits — as well as dairy foods, are excellent sources. A balance of potassium and sodium (as well as calcium) are essential for healthy blood pressure control. The following chart includes these numbers from some of our favorite potassium-rich foods:

Fruit

Apricots, dried
Serving Size: 1/4 cup
Amount of Potassium: 454mg
Amount of Sodium: 3mg

Cantaloupe
Serving Size: 1/4 medium-sized
Amount of Potassium: 412mg
Amount of Sodium: 12mg

Prunes
Serving Size: 1/4 cup
Amount of Potassium: 353mg
Amount of Sodium: 1mg

Banana
Serving Size: 1 small-sized
Amount of Potassium: 338mg
Amount of Sodium: 1mg

Kiwi
Serving Size: 1
Amount of Potassium: 215mg
Amount of Sodium: 2mg

Orange
Serving Size: 1 small-sized
Amount of Potassium: 174mg
Amount of Sodium: 0mg

Dairy

Skim milk
Serving Size: 1 cup
Amount of Potassium: 411mg
Amount of Sodium: 127mg

Cooked Beans

Pinto beans
Serving Size: 1/2 cup
Amount of Potassium: 531mg
Amount of Sodium: 2mg

Kidney beans
Serving Size: 1/2 cup
Amount of Potassium: 452mg
Amount of Sodium: 2mg

Lentils
Serving Size: 1/2 cup
Amount of Potassium: 374mg
Amount of Sodium: 2mg

Black beans
Serving Size: 1/2 cup
Amount of Potassium: 309mg
Amount of Sodium: 1mg

Vegetables

Potato, baked
Serving Size: 1 medium-sized
Amount of Potassium: 593mg
Amount of Sodium: 11mg

Winter squash, baked
Serving Size: 1 cup
Amount of Potassium: 590mg
Amount of Sodium: 8mg

Sweet potato, baked
Serving Size: 3/4 cup
Amount of Potassium: 528mg
Amount of Sodium: 15mg

Tomato, raw
Serving Size: 1/2 cup
Amount of Potassium: 94mg
Amount of Sodium: 3mg

Other

Blackstrap molasses
Serving Size: 2 tbsp
Amount of Potassium: 1218mg
Amount of Sodium: 39mg

You can find the potassium content of other foods by using the USDA FoodData Central database.