>It seems either someone has  a "food allergy" with allergy symptoms such as
hives,
>anaphylatic shock, rash, etc.   Others seem to have stomach upset
"Intollerances"
>to foods.  I have never met anyone that has both.
        I'm one! :)  I'm extremely allergic to dairy proteins (casein being
the worst offender) and to pineapple. I'm intolerant to soy in a big way and
can't handle animal source proteins either--eggs, meat of all kinds.

> One is digestive and one is
>immune system.  That is the general observation.
        From what I've studied (medical journals, trade journals, talks with
researchers in the dairy industry) I understand this a bit differently.
Dairy allergy is an inability to properly digest dairy-protein...where as
lactose intolerance is an inability to digest dairy-sugars. The following is
a brief summary of what I've learned in this process.
         In a those who are not allergic, the digestive process transpires
something along the lines of this: protein is eaten, the stomach digests, it
is broken down in the stomach and in the intestinal system where the body
absorbs the components in useable portions. In the protein allergic
individual this "normal" digestive process does not function 100% as it is
"intended."  The result is that instead of having amino acids(the building
blocks of protein)/usable strings of amino acids enter the blood stream,
larger "chunks (a.k.a. peptides)" enter. This is where the immune system
comes into play. You see, the body doesn't view these peptides as useful
strings of amino acids that the cells can use (as is the normal case)...and
instead these components are viewed as invaders in the body. The immune
system fuels up an all out attack to remove these "foreign" components and
in the process other cells can be damaged as the immune system in effect
becomes "over aggressive" (this is the way an allergic person might see it
but if these foreign components were a virus or other infectious agent, the
immune system is the unsung hero worth of praise). This is what causes the
"pain" associate with allergy and with prolonged exposure to the allergin
(those peptides in the blood stream) can cause heart damage, vital organ
damage, arthritis symptoms, and so on. The other thing that makes this
difficult is that opiate-like substance is released in this process...which
makes the allergic person very "addicted" to the very process that is
damaging them and accounts for the "fog" that comes with these kinds of
protein based allergies (dairy, soy, gluten). Many adults who are allergic
to dairy products feel they "could never give them up" and this is partially
due to the opiate-like secretions. So the allergy to protein isn't exactly
"non-digestive" and isn't exactly exclusively an immune "problem"--in fact
the immune system is doing exactly what it designed to do.
        Is there some research I missed? Please point me in the right
direction. :)