Grapefruit and grapefruit juice is nutritious and contains many important nutrients, including vitamin C, soluble fiber and potassium. In some cases, not getting enough potassium can cause your blood pressure to rise, so eating grapefruit may help you lower your blood pressure. People taking prescription medications should be careful about consuming grapefruit, however, as grapefruit can interfere with the clearance of some drugs, including those used for high blood pressure, increasing the side effects of these medications.
Talk to your doctor before you start any new medications if you consume grapefruit. Some of the substances in grapefruit can interfere with the liver's ability to break down medications, causing higher than normal blood levels of these drugs. This includes calcium channel blockers, which are often prescribed for the treatment of hypertension.
Consume grapefruit or grapefruit juice every day. According to Colorado State University, 1 cup of grapefruit juice contains 360mg of potassium and a half of a pink grapefruit contains 135mg of potassium. The University of Maryland Medical Center recommends that you get 2,000 mg of potassium each day, which will help you prevent high blood pressure, and consuming grapefruit can be a part of this plan.
Limit your sodium intake. Increasing your potassium intake may not be as effective at lowering your blood pressure if you also consume high amounts of sodium. Keep your sodium intake between 1,500 and 2,300mg per day.