Now there's yet another reason to keep a sharp eye on those blood-pressure numbers. In addition to increasing risk of stroke or heart attack, hypertension can also damage the kidneys.

High blood pressure damages the blood vessels in the kidneys, reducing the blood supply so that the kidneys are unable to do their job of removing fluids and waste products. Ultimately, this can lead to kidney failure, necessitating dialysis treatment or a transplant. High blood pressure is the cause of kidney failure in about 10 per cent of new patients.

Blood pressure -- the measurement of the force of blood on the walls of the arteries immediately after the heart beats (systolic pressure) and when the heart is at rest (diastolic pressure) -- shows how hard the heart is working and the condition of the blood vessels. The more difficult it is for blood to flow through the arteries, the higher the pressure will be. Numbers over 140/90 are considered "high."

Hypertension can be treated and controlled to reduce the chance of problems occurring. Lifestyle changes, such as healthy eating, exercise, not smoking and learning to relax, may help but medications are often prescribed to keep the pressure at normal levels.