Anxiety is an unpleasant mental state experienced by millions of men, women, and children worldwide. Though it is generally harmless, it can lead to more severe complications. Generally, symptoms are very minor, such as nervous pacing, difficulty sleeping, or the appearance of a nervous tick. However, in more serious cases, anxiety can lead to heart palpitations, nausea and vomiting, dizziness and headaches, even stroke and cardiac arrest. Fortunately, anxiety can be controlled by means of breathing exercises, meditation or yoga, and other simple relaxation techniques.