From the NAET website:
Q. "Then my symptoms are real? I'm not just imagining them?"         
A. No. You are not imagining them. Allergies in their mildest forms are merely nuisances. But for some people, accidental contact with an allergen can produce terrifying toxins in the body that result in clearly diagnosed illness just as though that person had taken a poison.

Diagnosis for either is not easy, but the milder the complaint, the harder it is for the patent to get good treatment. For instance, how do you treat a person for "feeling out of sorts, for a slight loss of memory, for a slight but persistent sore throat or cough, for a nagging, dull headache that does not respond to pain medications, for a persistent backache or a tingling feeling in the arms and hands that cannot be diagnosed by a neurologist?" Some of these unfortunate people have seen their physicians so many times that they cannot tell you how many times they have been ignored, diagnosed as suffering from a "nervous disorder" or been labeled a hypochondriac.

Of course, that's not actual hypochondria, that's undiagnosed allergies looking like hypochondria. Maybe hypochondria is an allergy on the psychological level that results in a real symptom from an emotional situation? After all, even emotions are electrochemical reactions in the body. Who knows? *shrug*