People with anxiety problems are usually split into two camps: One side is convinced that they're nuts; the other thinks that they have major medical problems that will attack their brain, heart, or some other organ they can't live without. And you know what? The second camp might be on to something. But don't freak out. Although there are medical problems that do in fact cause anxiety, they're not all incurable nightmares. For instance... Thyroid Problems Most anxious people like to think big in terms of what might be ailing them. You