Everybody has heard that hypertension (high blood pressure) is one of the main causes of stroke and cardiovascular disease, which, in turn, can lead to death. But not so many people know what causes hypertension.
As blood flows through the body, it pushes against the walls of the arteries. This force in the arteries is what is called "blood pressure." Essentially, blood pressure represents the relationship between the volume of blood and the area of a cross-section of the artery at any given point. Blood pressure measurements include systolic pressure, which is read when the heart is constricted, and diastolic pressure, which is read when the heart is dilated. Normal systolic blood pressure is less than 130 mmHg and normal diastolic blood pressure is less than 90 mmHg.
If obesity and/or hyperlipidemia (high cholesterol or triglyceride fat levels in the blood) cause the wall of the artery to become narrow and atherosclelotic (hardened), blood pressure becomes high. Blood pressure also rises when there is an increase in blood volume caused by excess water retention in the body. For example, high salt intake increases blood volume and thereby leads to hypertension.