High blood pressure alarm: Many people don't have these 23 facts on their radar. High blood pressure starts at 140/90 mmHg (see right).

However, it depends on where and how the measurements are taken. Hypertension can cause severe damage to the retina and even go blind, says Professor Martin Halle from the Munich University Hospital Rechts der Isar. Since high blood pressure is practically a protuberance of the eye, the ophthalmologist can determine whether a patient suffers from high blood Pressure with a simple examination.