Blood pressure is given as a reading of two numbers, such as 110/70. The higher number (systolic) is the pressure when the heart beats. The diastolic, or lower number shows the pressure between the heartbeats, while the relaxed heart is refilling with blood. Normal blood pressure readings are lower than 120/80. The cause of most hypertension is unknown. Occasionally, conditions of the kidney or adrenal gland are the cause of high blood pressure.

Although it's most common in older adults, hypertension can also affect children. The normal blood pressure for a child is dependent upon the child's age, gender, and height. Your doctor can tell if your child's blood pressure is abnormal. Children are at higher risk for hypertension if they are overweight, African-American, or if they have a family history of the condition. Children with high blood pressure may benefit from the DASH diet and taking medications. Children with high blood pressure should also maintain a healthy weight and avoid tobacco smoke.
The cause for hypertension is not always known, although it can develop as a result of other health conditions including: sleep apnea, kidney problems, and thyroid issues. Beyond chronic health conditions, risk factors for hypertension include age, the amount of salt you eat, being overweight or obese, using tobacco, drinking excessively, not exercising, and having too little potassium in your diet.
Unchecked, high blood pressure can lead to a myriad of serious health problems, such as heart attacks, strokes, and other forms of heart disease and kidney disease. It is extremely dangerous during pregnancy because it contributes to devastating and even deadly problems for moms and babies. Other impacts of hypertension include vision problems and sexual dysfunction.
Stress reduction techniques such as biofeedback or transcendental meditation may be considered as an add-on to other treatments to reduce hypertension, but do not have evidence for preventing cardiovascular disease on their own.[125][126][127] Self-monitoring and appointment reminders might support the use of other strategies to improve blood pressure control, but need further evaluation.[128]