Depression has been called “the common cold of mental illness,” and it affects more than nine million Americans. Anxiety disorders affect millions more. People who suffer from one of these illnesses also have the other more often than not. From 60 to 70% of people with depression also suffer from anxiety. About half of all patients with anxiety disorders also suffer depression. There’s so much overlapping between depression and anxiety that many psychologists are beginning to view them as part of the same disorder.