Banana vs. Potassium Pills

Potassium is essential for nerve and muscle function and maintaining healthy blood pressure levels. Many Americans don't get enough of this essential mineral, according to Colorado State University Extension. This is compounded by the high intakes of sodium typical in the U.S., which further increase the need for potassium. Potassium helps your body get rid of the extra sodium to maintain the proper balance of water in the body. It is better to get your potassium from food, however, than from supplements.

A medium banana has about 422 milligrams of potassium, or 12 percent of the daily value for potassium. You'd have to eat more than eight bananas to get a full day's worth of potassium. Potassium pills make it easier to consume higher doses of potassium, which is why there can be a risk of potassium toxicity when taking these supplements. Over-the-counter potassium supplements, however, only contain 3 percent of the daily value for potassium in each pill, which is equal to 99 milligrams or 2.5 milliequivalents, which limits the risk of overdoses. Prescription pills, on the other hand, can have much higher levels of potassium. The most common prescription potassium supplements contain either 8 or 10 milliequivalents of potassium per pill.

Potassium pills only provide potassium, but bananas also provide a variety of other nutrients. Each medium banana contains 12 percent of the daily value for fiber, 17 percent of the DV for vitamin C, 22 percent of the DV for vitamin B-6 and 16 percent of the DV for manganese. Fiber can help lower your risk for constipation, high cholesterol and heart disease, and both vitamin C and manganese act as antioxidants to help prevent cell damage from substances called free radicals. Vitamin B-6 is essential for forming red blood cells and proper immune function.

Bananas aren't likely to cause any adverse effects. Potassium supplements, however, can cause side effects such as nausea, diarrhea, stomach irritation, slowed heart rate, muscle weakness and abnormal heart rhythms. If your kidneys aren't working properly, consuming too much potassium from supplements could cause sudden death. Potassium supplements aren't recommended unless you are under the supervision of a doctor.

Potassium pills may also interact with other medications, including ACE inhibitors, NSAIDs, angiotensin receptor blockers, beta-blockers, cyclosporine, heparin and an antibiotic commonly called Bactrim or Septra. These medications can increase the risk of your blood potassium levels becoming too high, a condition called hyperkalemia. These supplements may also increase the risk of dangerous side effects when taking digoxin, which is used to treat heart failure and abnormal heart rhythm.