Blood Pressure

Blood pressure is the force of the blood on the artery walls as the heart pumps blood through the body. The arteries are the blood vessels that carry blood from the heart to the rest of the body.

The heart pumps blood through the blood vessels by contracting. Each time the heart contracts, the blood pushes harder against the walls of the arteries than it does when it rests between beats. This means that the pressure of the blood on the artery walls is greatest each time the heart contracts. This is the systolic pressure, the higher (upper) number in a blood pressure reading.

When the heart rests between beats, the pressure of blood on artery walls is lower. This is the diastolic pressure, the lower number in a blood pressure reading.

These 2 levels of blood pressure--systolic and diastolic--are measured when someone takes your blood pressure. For example, in the blood pressure reading of 120/80, 120 is the systolic pressure (the pumping pressure) and 80 is the diastolic pressure (the resting pressure). The pressures are measured in millimeters of mercury.

Normal, healthy blood pressure is less than 120/80 ("120 over 80"). The upper number (120) is the pressure when the heart pushes blood out to the rest of the body (systolic pressure). The bottom number (80) is the pressure when the heart rests between beats (diastolic pressure).

Blood pressure can rise and fall with exercise, rest, emotions, or pain. However, if you have several measurements over 120/80, you probably have pre-high or high blood pressure.

• Pre-high blood pressure (prehypertension) is between 120/80 and 139/89.
• Stage I high blood pressure ranges from 140/90 to 159/99.
• Stage II high blood pressure is over 160/100.

The higher your blood pressure, the greater your risk of having a stroke and other serious medical problems.

You can do the following things to help keep your blood pressure under control:

• Maintain a healthy body weight. Avoid being overweight.
• Follow the DASH diet. This diet is low in fat, cholesterol, red meat, and sweets. It emphasizes fruits, vegetables, and low-fat dairy foods. The DASH diet also includes whole-grain products, fish, poultry, and nuts.

  For more information, see DASH diet.

• Use less salt. Check the levels of sodium listed on food labels. Avoid canned and prepared foods unless the label says no salt is added.
• Try not to have too much caffeine in your diet.
• Include regular physical activity in your schedule, after checking with your healthcare provider.
• If you are a woman, do not have more than 1 drink of alcohol a day. Men should not have more than 2 drinks a day. (Alcohol raises your blood pressure.)
• Try to reduce the amount of stress in your life, or learn techniques to help you relax and cope with stress better.
• If you take medicine for high blood pressure, always follow your healthcare provider's instructions. Don't take less medicine or stop taking medicine without talking to your provider first. It can be dangerous to suddenly stop taking blood pressure medicine. Also, do not increase your dosage of any medicine without first talking with your provider.

If your blood pressure is normal, check it once a year. If it's above normal, follow the schedule for checkups recommended by your healthcare provider.