Every two seconds, someone in the world has a stroke. One out of every six people will have a stroke at some point in their lives. Strokes deprive brain cells of oxygen and are one of the most common causes of death, and a leading cause of preventable disability. But what causes strokes in the first place? And what can doctors do to treat them? Vaibhav Goswami takes us into the body to find out.

[TED Ed]