Everyone experiences anxiety from time to time – it is a normal human emotion, after all.  We feel nervous or anxious at work, before a big exam or when making crucial decisions in our life. For some, however, anxiety goes beyond being just a passing feeling. Instead, it causes such great distress that affects their ability to live a normal life.  This is when anxiety becomes a disorder. Anxiety disorders affect about 18 percent of the American population, making them the most common mental illnesses in the country.  That means that at any given time, about 40 million are suffering from some sort of anxiety disorder.