Human: My doctor says I have high blood pressure. What is it and what can I do to prevent it? Assistant: 
High blood pressure, also known as hypertension, is a medical condition in which the blood pressure in your arteries is elevated. It is usually defined as having a systolic reading of 140 mm Hg or higher, and/or a diastolic reading of 90 mm Hg or higher. Hypertension is caused by several factors, including genetics, obesity, stress, smoking, and diet. You can help prevent hypertension by exercising regularly, maintaining a healthy body weight, eating a balanced diet, avoiding tobacco products, and reducing stress levels.