"My family's food choices have always been pretty good. We eat a lot of fruit, vegetables, and low-fat yogurt." — Lily Kramer
Blood pressure is the force of blood against artery walls. It is measured in millimeters of mercury (mmHg) and recorded as two numbers—systolic pressure (when the heart beats) over diastolic pressure (when the heart relaxes between beats). Both numbers are important. (See box 1)
Blood pressure rises and falls during the day. But when it stays elevated over time, then it's called high blood pressure. High blood pressure is dangerous because it makes the heart work too hard, and the high force of the blood flow can harm arteries and organs such as the heart, kidneys, brain, and eyes. High blood pressure often has no warning signs or symptoms. Once it occurs, it usually lasts a lifetime. If uncontrolled, it can lead to heart and kidney disease, stroke, and blindness.
High blood pressure affects more than 65 million—or 1 in 3— American adults. About 28 percent of American adults ages 18 and older, or about 59 million people, have prehypertension, a condition that also increases the chance of heart disease and stroke. High blood pressure is especially common among African Americans, who tend to develop it at an earlier age and more often than Whites. It is also common among older Americans—individuals with normal blood pressure at age 55 have a 90 percent lifetime risk for developing high blood pressure.
High blood pressure can be controlled if you take these steps:
- Maintain a healthy weight.
- Be moderately physically active on most days of the week.
- Follow a healthy eating plan, which includes foods lower in sodium.
- If you drink alcoholic beverages, do so in moderation.
- If you have high blood pressure and are prescribed medication, take it as directed.
All steps but the last also help to prevent high blood pressure.
Box 1: Blood Pressure Levels for Adults*
|Category||Systolic** (mmHg)***||Diastolic** (mmHg)***||Result|
|Normal||Less than 120 and||Less than 80||Good for you!|
|Prehypertension||120-139 or||80-89||Your blood pressure could be a problem. Make changes in what you eat and drink, be physically active, and lose extra weight. If you also have diabetes, see your doctor.|
|Hypertension||140 or higher or||90 or higher||You have high blood pressure. Ask your doctor or nurse how to control it.|
* For adults ages 18 and older who are not on medicine for high blood pressure and do not have a short-term serious illness. Source: The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure; NIH Publication No. 03-5230, National High Blood Pressure Education Program, May 2003.
** If systolic and diastolic pressures fall into different categories, overall status is the higher category.
*** Millimeters of mercury.