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There are different types of allergy. The
immediate or type 1 hypersensitivity is easily recognized because it
involves quick and dramatic symptoms. Hay fever is the most common
expression of allergy and is a prototype of immediate hypersensitivity.
Hay fever is a reaction to airborne plant pollens in the nose. Allergy tests are positive, antihistamines help and allergy shots can reduce the
reactivity over time.
Delayed patterns of allergy are not so obvious and
generally go unrecognized. Allergy skin tests do not show this problem nor do IgE antibody
tests.
Common specific problems obviously related to allergy include hay fever, asthma,
rhinitis, otitis media, atopic dermatitis, urticaria, and anaphylaxis
Shrinking Definition of Allergy
The reason for the definition of "allergy" to shrink toward a
narrowly-defined clinical practice probably was the skin test. If anything distinguished
an allergist from his/her colleagues, it was the skin test. By a practical evolution of
allergy practice, those clinical problems which were diagnosable by skin reactions became
the special property of allergists. Allergy therapy became synonymous with desensitization
(immunotherapy) injections.
However, the original definition of the terms
"allergy" and "atopy" applied to a larger,
ever expanding list of immune-mediated "strange diseases" which plagued us
increasingly in the 20th century of extravagant biological misadventures.
The immune-mediated diseases appear to be increasing into the 21st century
and may become the overwhelming health problems of the future.
For some time, it has been appreciated that food allergy operates in a more complex and
mysterious way than inhaled allergy. Although skin tests were used to test for food
sensitivity, many allergists also prescribed various kinds of low allergy or elimination
diets on clinical grounds with satisfactory results. Allergists generally appreciated that
allergy shots containing food antigens were not helpful. Nevertheless, the IgE model was
the easiest route to follow in the study of food allergy.
Many of the major unsolved diseases of our civilization are either degenerative and/or
inflammatory and many are recognized to be immune-mediated or hypersensitivity diseases.
Asthma, allergy, rheumatic diseases, autoimmune diseases, multiple sclerosis,
diabetes, thyroiditis, psoriasis are examples of hypersensitivity diseases which involve
humoral and cell-mediated immunity. We use celiac disease - wheat allergy- as a prototype
of food allergy which demonstrates the prolific ability of food allergy to produce a wide
range of serious diseases. The major endemic diseases, atherosclerosis,
diabetes 2 and Alzheimer's dementia appear to have common roots that
involve both the food -supply and immune-mediated inflammation. We think
that all alert scientists need to consider at least two features of
the food supply:
1. the metabolic consequences of food
choices
2. the ability of foods to initiate and
sustain immune-mediated disease ( inflammation).
An important concern is the possibility that the chemical soup created by our
civilization drives increasing numbers of individuals into hypersensitivity illness. The
theory is that substances in the air, water and food supply can drive immune
networks into hypersensitive states and produce a variety of diseases. Commonly quoted "expert" opinions tend to minimize the incidence and
importance of food allergy. While the dogma is misleading, it represents vested interests
and is remarkably persistent.
The type 1 model of allergy is attractive to
physicians and researchers, because of its relative simplicity and the ease of testing for
sensitization; but, it selects only a special population of people with IgE-mediated
allergy. While this is an important reaction pattern, some physicians have claimed it is
the only valid form of allergic reactions to food. Their opinion is no
longer acceptable. A
distinction between immediate, obvious allergic reactions and delayed, less obvious,
chronic immune injury is useful.
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