Prehypertension is being recognized as the early warning sign of cardiovascular disease. It was recognized officially 10 year ago in The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC7)(1), which is a guideline for physicians who treat hypertension. However, many people do not realize they have hypertension or prehypertension.


Prehypertension is systolic blood pressure between 139 and 120, and diastolic blood pressure between 89 and 80. It is associated with an increased risk of stroke and cardiovascular disease (CVD) (1,2,3). The risk is not as much as when systolic is over 140 or diastolic over 90, but it is twice as much as those who are below the prehypertensive levels.

Giving these blood pressure levels a name and recognizing that there is greater risk with these levels is a step forward. But as pointed out in the last post, for diastolic blood pressure, lower is better to at least 70.

For those between ages 40 and 70 every increase of 20 mm Hg in systolic blood pressure or every increase of 10 mm Hg diastolic will increase the risk of CVD twofold (2). This is true for all blood pressure between 115/75 and 185/115. So if your blood pressure is 135/85, you have twice the risk of getting CVD than if your blood pressure is 115/75. If your blood pressure is 155/95, it is 4 times as much risk. If 175/105, it is 8 times as much.

Why Prevention Is Important

One problem is that if the blood pressure gets to the point it requires treatment, the treatment is not all that effective. By the year 2000, only 34% of patients had achieved adequate control of their blood pressure. This was mostly because patients did not change lifestyle or because the medications failed. Many times medication failure is related to medication side effects.

In both lifestyle change and medication failure, motivation plays a big part. If the medications make you feel weak, feel dizzy, lose mental focus or lose sexual response, you lose motivation to prevent a stroke in the distant future. It is difficult to maintain motivation for the months on end it takes to see blood pressure changes from exercise and weight loss.

If You Are Hypertensive, You Must Stay On Your Medications

There is no question that if you are on medications you must stay on them. Only as your blood pressure improves and your doctor decides to reduce your medications should you change medications. The reduction in stroke and cardiovascular disease in those with lowered blood pressure from medication is dramatic.

But if medications can be reduced, side effects should improve. And if medications can be stopped, it would be best of all. For my wife's osteoporosis (another disease that can be improved by a high potassium diet), it took several months for her physician to lower my wife's thiazide diuretic and then take her off it. Expect your physician to be cautious.

How To Prevent Hypertension And Prehypertension

It would be far better to prevent hypertension and prehypertension in the first place. This can be done through lifestyle changes. Lack of lifestyle changes play a big part in hypertensive medication failure. Control of weight, alcohol consumption, physical activity and diet are as important for prevention as they are for treatment.

If your blood pressure is “normal” or prehypertensive, begin to incorporate high potassium foods into your diet. It is the easiest way to begin reducing your blood pressure. A high ratio of potassium to sodium in your diet is the quickest way to see results.

Other lifestyle changes will add even more improvement, but will take longer to show results. Keeping alcohol consumption under 1 to 2 drinks per day, losing weight and increasing physical activity are lifestyle changes that will help most hypertensives.

Reducing weight and increasing physical activity both should be done slowly to allow the body to adapt. If you are overweight, reducing weight will improve systolic blood pressure 5 to 20 mm Hg for every 22 pounds you lose above normal (3). Increasing your physical activity can reduce systolic blood pressure by 4 to 9 mm Hg.

If on the usual American diet, a high potassium foods diet can be expected to reduce blood pressure by 5 to 22 mm Hg.

Tables Of High Potassium Foods

To find tables that have potassium and sodium content of foods in various food groups, click here. It lists many of the posts on this website. Those with tables have “table” in the link. Or you can have a PDF with tables sent to you by signing up below.

The Seventh Report of the Joint National Committee on
Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC7)

1. full report

2. short report

3. physician card