How Potassium Can Help Control High Blood Pressure

Understanding the heart-healthy benefits of potassium

Foods that are rich in potassium are important in managing high blood pressure, also known as hypertension, because potassium lessens the effects of sodium. The more potassium you eat, the more sodium you lose through urine. Potassium also helps to ease tension in your blood vessel walls, which helps further lower blood pressure.

Increasing potassium through diet is recommended in adults with blood pressure above 120/80 mm Hg who are otherwise healthy. Potassium can be harmful in patients with kidney disease, any condition that affects how the body handles potassium or those who take certain medications. The decision of whether to take excess potassium should be discussed with your doctor. 

Potassium and your diet

The recommended potassium intake for an average adult 19-50 years of age is 3,400 milligrams (mg) per day for men and 2,600 mg per day for women.

Many of the elements of the DASH (Dietary Approaches to Stop Hypertension) diet — fruits, vegetables, fat-free or low-fat (1 percent) dairy foods and fish — are good natural sources of potassium. For example, a medium banana has about 226 mg of potassium and half a cup of plain mashed sweet potatoes has 456 mg.

Other potassium-rich foods include:

  • Apricots and apricot juice
  • Avocados
  • Cantaloupe and honeydew melon
  • Fat-free or low-fat (1 percent) milk
  • Fat-free yogurt
  • Grapefruit and grapefruit juice (talk to your health care professional if you’re taking a cholesterol-lowering drug)
  • Greens
  • Halibut
  • Lima beans
  • Molasses 
  • Mushrooms
  • Oranges and orange juice
  • Peas
  • Potatoes
  • Prunes and prune juice
  • Raisins and dates
  • Spinach
  • Tomatoes, tomato juice and tomato sauce
  • Tuna

picnic with grandpa and his grandkids

Potassium is only one component of a well-rounded plan for blood pressure health.

Even though potassium can lessen the blood pressure-raising effects of sodium, eating more potassium should be combined with your efforts to break up with that excess salt and develop other healthy eating and lifestyle habits.

Is it possible to have too much potassium?

Too much potassium can be harmful in people with kidney disorders. As kidneys become less able to remove potassium from your blood, too much potassium may build up.

Often, levels of potassium must be severely high (hyperkalemia) before symptoms occur. Nausea, vomiting, irregular pulse, shortness of breath and chest pain may occur with high levels of potassium. Feeling sick to your stomach, a low, weak or irregular pulse and fainting may occur with high levels of potassium.

Consult with a health care professional before taking any over-the-counter potassium supplement. You should also ask your health care professional before trying salt substitutes, which can raise potassium in people with certain health conditions and those taking ACE inhibitors for high blood pressure.