How high blood pressure works .
High Blood Pressure.

What causes high blood pressure?
Food, medicine, lifestyle, age, and genetics can cause high blood pressure. Your doctor can help you find out what might be causing yours. Common factors that can lead to high blood pressure include:

A diet high in salt, fat, and/or cholesterol
Chronic conditions such as kidney and hormone problems, diabetes, and high cholesterol
Family history, especially if your parents or other close relatives have high blood pressure
Lack of physical activity
Older age (the older you are, the more likely you are to have high blood pressure)
Being overweight or obese
Race (non-Hispanic black people are more likely to have high blood pressure than people of other races)
Some birth control medicines and other medicines
Stress
Tobacco use or drinking too much alcohol
How is high blood pressure diagnosed?
High blood pressure is diagnosed with a blood pressure monitor. This is a common test for all doctor visits. A nurse will place a band (cuff) around your arm. The band is attached to a small pump and a meter. They will squeeze the pump. It will feel tight around your arm. Then they will stop and watch the meter. This provides the nurse with 2 numbers that make up your blood pressure. The top number is your systolic reading (the peak blood pressure when your heart is squeezing blood out). The bottom number is your diastolic reading (the pressure when your heart is filling with blood­). You may also hear the doctor or nurse say a blood pressure is “120 over 80.”

Normal blood pressure is less than 120 on top and less than 80 on the bottom.
Prehypertension levels are 120-139 on top and 80-89 on the bottom.
High blood pressure, stage 1 is 140-159 on top and 90-99 on the bottom.
High blood pressure, stage 2 is 160 or higher on top and 100 and over on the bottom.
The higher your blood pressure is, the more often you need to have it checked. After age 18, have your blood pressure checked at least once every two years. Do it more often if you have had high blood pressure in the past.

Can high blood pressure be prevented or avoided?
If your high blood pressure is caused by lifestyle factors, you can take steps to reduce your risk:

Lose weight
Stop smoking
Eat properly
Exercise
Lower your salt intake
Reduce your alcohol consumption
Learn relaxation methods
If your high blood pressure is caused by disease or the medicine you take, talk to your doctor. They may be able to prescribe a different medicine. Additionally, treating any underlying disease (such as controlling your diabetes) can help reduce your high blood pressure.