Potassium is a mineral that most of us get every day through the foods we regularly eat — and that's a good thing. "Potassium is a mineral necessary for good health," explains Alexa Schmitt, a clinical nutritionist at Massachusetts General Hospital. "It aids in maintaining heart health by helping to regulate the fluid balance in the body." 

Potassium is classified as an electrolyte, which means that it carries an electric charge in your body. The body needs balanced amounts of electrolytes — including potassium, sodium, magnesium, and others — to keep the blood chemistry at the right levels so that your body can function at its best. Potassium also helps your body put the protein you eat to work, building muscle, bones, and other cells. 

Who Needs to Pay Attention to Potassium?
Even though potassium helps our bodies in many ways, Schmitt says she cannot simply make a blanket recommendation about eating more potassium. That's because different people need different amounts of potassium, depending on their overall health.
So who needs to watch their potassium intake?
  • People with kidney disease are at risk of having too much potassium in the blood. They tend to retain potassium because their kidneys don't get rid of extra potassium as normal kidneys would. Hyperkalemia, or high levels of potassium in the blood, can be caused by a number of things (including certain medications and hormonal deficiencies), but kidney disease is the most common culprit. High levels of potassium can lead to irregular heartbeats. Therefore, your doctor may periodically check your potassium levels, especially if you have kidney disease.
  • People with high blood pressure are at increased risk for having low potassium levels (hypokalemia) because some high blood pressure medications can deplete potassium levels in the blood. Other conditions that can cause low potassium include vomiting, diarrhea, and eating disorders. Certain laxatives and diuretics have been found to cause low potassium as well. Low potassium is characterized by weakness, fatigue, constipation, and muscle cramps. If your potassium level becomes too low, it can also affect your heartbeat. Talk with your doctor about monitoring your potassium levels if you take high blood pressure medication or have a condition that may cause low potassium.
Foods High in Potassium
Though a lot of people associate bananas with potassium, there are a number of other foods that are high in potassium, which Schmitt defines as having at least 350 milligrams of potassium per serving.
In addition to bananas, Schmitt’s high-potassium food favorites include dried apricots, cantaloupe, beets, figs, honeydew melon, and orange juice. "Cantaloupe and honeydew are great [for potassium] because people tend to eat more cantaloupe in one sitting than they would bananas or dried apricots,” she says. Other foods that are high in potassium include potatoes (with the skin on), soy products, dairy products, and meats.
Many of us already enjoy foods that are high in potassium, but if you’re worried about your potassium intake because of conditions such as high blood pressure or kidney disease, talk to your doctor or see a nutritionist. They can help you plan a healthy diet.