According to the American Heart Association, nearly one in three adults in the United States has high blood pressure. But nearly one-third of those people don't know they have high blood pressure, because it's a silent disease. People can have high blood pressure for years without experiencing symptoms or knowing they have it.
The upper or first number in a blood pressure reading is the systolic pressure and the lower or second number is called the diastolic pressure. According to National Heart, Lung, and Blood Institute guidelines:
- Normal blood pressure is below 120/80 mmHg.
- Prehypertension is systolic pressure that's between 120 to 139 or diastolic pressure between 80 and 89.
- Stage 1 hypertension is systolic pressure between 140 to 159 or diastolic pressure between 90 and 99.
- Stage 2 hypertension is systolic pressure higher than 160 or diastolic pressure of 100 or higher.
