Blood pressure is sort of like the weather. Everyone talks about it, but not enough people do anything about it. It’s often called the silent killer because, for the most part, it has no symptoms. Headaches associated with blood pressure are relatively rare. Blood pressure is the force of our blood pushing against the walls of our arteries. As our hearts beat, typically 60 to 70 times a minute when we’re sitting or lying down, blood is forced into and through the arteries. Blood pressure is highest when the heartbeats, pumping that blood. That’s the systolic pressure. Between beats, when the heart is at rest, blood pressure falls. That’s the dias-tolic pressure.

Blood pressure is expressed as the systolic pressure over the diastolic pressure, as in 120 over 80, written as 120/80. Blood pressure is the force with which the blood presses against the arterial walls as it circulates. In a person with high blood pressure, or hypertension, this force is greater than normal and causes the arterial walls to narrow and thicken, putting extra strain on the heart. Blood pressure fluctuates even in healthy individuals. It tends to increase with physical activity, excitement, fear, or emotional stress, but such elevations are usually transient. Most physicians will not make the diagnosis of hypertension unless the pressure is high on at least three separate occasions, obesity, alcohol and sugar intake, and hereditary and ethnic factors all contribute, as will diabetes, kidney disease, and pregnancy. It is usually only when the secondary complications—damage to the arteries, brain, eyes, or elsewhere in the body—have developed that symptoms occur, by which time the condition is serious

Symptoms

Mild hypertension has no symptoms.
Severe hypertension: headaches, shortness of breath, visual disturbances, giddiness In Nigeria at least 25 million people have hypertension.
Hypertension is usually described as being a systolic pressure greater than 139, or a diastolic pressure greater than 89, or both. The World Health Organization defines it as being consistently above 160mm. Hg. systolic, and 95mm. Hg. Diastolic.
In the U.K. high blood pressure is extremely common, affecting 10–20 percent of the
adult population.
High blood pressure is more frequent and more severe in African than white
population. It is uncommon in children and adolescents.
In societies that consume little or no salt the incidence of hypertension is extremely low