What is anxiety?

Anxiety starts in brain areas such as the amygdala, which trigger the fight-or-flight response and flood the body with adrenaline and cortisol. In short bursts this is useful, sharpening focus before an exam or helping us react to danger. Anxiety disorders occur when the alarm fires too often, too strongly or without a real threat, and they include generalised anxiety disorder, panic disorder and phobias. The World Health Organization estimates that about 301 million people had an anxiety disorder in 2019, making them the most common mental disorders in the world. They are highly treatable with talking therapies such as cognitive behavioural therapy, lifestyle changes and, in some cases, medication.