Hypertension (High blood pressure): It is the common disease affecting heart and blood vessels. A blood pressure of 120/ 80 is considered normal, but the increase in blood pressure beyond 140mmHg (systolic) and 90mmHg (diastolic) is called high blood pressure (hypertension). High blood pressure can harm heart, brain, kidneys and eyes. Hypertension can be due to mental stress, tobacco smoking, and intake of diet having high cholesterol.