Research is inconsistent as to whether nutritional deficiencies (for example, zinc or magnesium deficiency) may be risk factors for panic disorder. While food additives like aspartame, alone or in combination with food dyes, are suspected to play a role in the development of panic attacks in some people, it has not been confirmed by research so far.
Panic disorder is a diagnosis given to people who experience recurrent unexpected panic attacks— that is, the attack appears to occur from out of the blue. The term recurrent refers to the fact that the individual has had more than one unexpected panic attack. In contrast, expected panic attacks occur when there is an obvious cue or trigger, such as a specific phobia or generalized anxiety disorder. In the U.S., roughly 50% of people with panic disorder experience both unexpected and expected panic attacks.
Anxiety disorders increase one's chances for suffering from other medical illness, such as cardiovascular disorders, including obesity, heart disease and diabetes. More specifically, increased body weight and abdominal fat, high blood pressure, and greater levels of cholesterol, triglycerides, and glucose have all been linked to anxiety. While it is still unclear what causes the high co-morbidity between anxiety and bad physical health outcomes, research suggests that changes in underlying biology that is characteristic of anxiety may also facilitate the emergence for these other physical health outcomes over time. For example, changes in stress hormones, autonomic responses, as well as heightened systemic inflammation are all associated with anxiety disorders and negative health outcomes. These shared physiological states suggest a shared underlying biology and that anxiety maybe a whole-body condition.
Panic attack symptoms and heart attack symptoms can seem similar because their signs and symptoms can be similar. Most medical professionals, however, can quickly tell the difference between their symptoms as heart attacks have distinct symptoms that aren’t panic attack like. If you are unsure of which is panic attack symptoms and which is heart attack symptoms, seek immediate medical advice. If the doctor believes your symptoms are those of a panic attack, you can feel confident his or her diagnosis is correct. Therefore, there is no need to worry about a heart attack.
Generalized anxiety disorder involves persistent and excessive worry that interferes with daily activities. This ongoing worry and tension may be accompanied by physical symptoms, such as restlessness, feeling on edge or easily fatigued, difficulty concentrating, muscle tension or problems sleeping. Often the worries focus on everyday things such as job responsibilities, family health or minor matters such as chores, car repairs, or appointments.
Panic disorder is characterized by uncontrollable, recurrent episodes of panic and fear that peak within minutes. Panic attacks are accompanied by physical manifestations, such as heart palpitations, sweating, and dizziness as well as the fear of dying or becoming insane. Worry about having an attack may lead to additional anxiety and avoidance behaviors or to other problems in functioning.
Psychodynamic theory posits that anxiety is often the result of opposing unconscious wishes or fears that manifest via maladaptive defense mechanisms (such as suppression, repression, anticipation, regression, somatization, passive aggression, dissociation) that develop to adapt to problems with early objects (e.g., caregivers) and empathic failures in childhood. For example, persistent parental discouragement of anger may result in repression/suppression of angry feelings which manifests as gastrointestinal distress (somatization) when provoked by another while the anger remains unconscious and outside the individual's awareness. Such conflicts can be targets for successful treatment with psychodynamic therapy. While psychodynamic therapy tends to explore the underlying roots of anxiety, cognitive behavioral therapy has also been shown to be a successful treatment for anxiety by altering irrational thoughts and unwanted behaviors.
Social Anxiety Disorder;Fear of social situations in which the person is exposed to unfamiliar people or to possible scrutiny by others. The individual fears that he or she will act in a way (or show anxiety symptoms) that will be embarrassing and humiliating, often times leading to avoidance of social situations and severe distress when participation in social situations can't be avoided. 
So how do you know if your anxiety is “normal” or “excessive?” It’s normal to be worried about an upcoming test or wondering how you are going to cope financially when you unexpectedly find out you need major repairs done to your house. If you are suffering from the type of excessive worry that accompanies Generalized Anxiety Disorder, you may see a report on the local news about a new health scare in a different country and stay awake at night worrying about you or your family being affected, even though risks are minimal at best. You will likely spend the next few days and weeks in a constant state of worry about the well-being of your family and experience anxiety that is debilitating, intrusive, excessive, and persistent.
In order to manage threatening situations, humans have evolved to experience a "fight or flight" response. As part of this response, when humans are confronted with a dangerous situation, their body mobilizes by sending blood away from their extremities (e.g. hands and feet) and into the major muscles, producing adrenaline, and increasing heart rate so that we are better equipped to fight off danger.
Before SSRIs and SSNRIs became available, medications from the group known as the tricyclic antidepressants (TCAs) were often used to address panic disorder. Although TCAs have been found to be equally effective in treating panic attacks, SSRIs and SSNRIs have been proven to be safer and better tolerated. Therefore TCAs are used much less often than they were previously.
A helpful approach to distinguishing normal anxiety from an anxiety disorder is to identify the cause of the anxiety, and then assess whether the anxiety symptoms are a proportional response to it. Worries, fears, and intrusive thoughts that are extreme, unrealistic, or exaggerated and interfere with normal life and functioning could constitute an anxiety disorder. For instance, being concerned about getting sick and taking steps to avoid germs, like using hand sanitizer and avoiding touching door handles, does not necessarily constitute an anxiety disorder; however, if the concern about sickness makes it difficult to leave the house, then it is possible that the person suffers from an anxiety or anxiety-related disorder.
Panic attacks, a hallmark of panic disorder, are sudden and repeated bouts of overwhelming fear. These attacks, which often begin in adolescence or early adulthood, are much more intense than normal feelings of anxiety or stress. They usually pass after a few minutes and typically last no longer than an hour, but can continue to recur throughout a day.