At the moment, my nose is running like
a faucet, my eyes are red and teary and my throat feels like
it's on fire. Do I have an allergy? No, not this time, I've
got a cold. The symptoms are rather similar but the cause
is quite different.
We often use the term
"allergy" as a shorthand because explaining "adverse
reaction" requires more work, but "allergy"
is a very specific technical term that implies a series of
chemical reactions in your body. Just because you may be experiencing
some of the symptoms that are in common with an allergic reaction
doesn't mean you're having an allergic response.
Food allergies are very rare and often life
threatening. Minute amounts of an allergen can trigger a response
in the body, flooding the blood with chemicals called "histamines'
in response to a misperceived invasion. (This is why we take
"anti-histamines" to combat allergic responses)
In the case of an allergy to pollens, the site of response
is mainly in the nose, sinuses and eyes. In the case of a
food allergy, the response is mainly in the mouth, throat,
stomach and intestines. In cases of severe food allergy, anaphylactic
shock may result, causing death if not treated immediately.
Very few people have true food allergies and when they do
the results are often violent and dramatic, leaving no room
A more accurate term for the reaction that
some people have to food additives would be "food intolerance".
This would include feelings of lightheadedness from eating
food containing MSG or Aspartame to the gassy feeling after
consuming beans or dairy products (hence the term "lactose
intolerant") Food intolerances may range from mild to
severe - from simple feelings of discomfort to vomiting or
diarrhea. While the response may not be pleasant, it's very
rarely life threatening and shouldn't be confused with a true
allergic response. Food Intolerance tends to be dosage related
- you might be able to tolerate small amounts of cheese without
a problem but eating a pizza can be the cause of distress.
Even if you're food intolerant, you may be able to consume
small amounts without any ill effect - this would not be the
case if it were a true food allergy.
What kind of responses can you have from
a food intolerance? Almost any. While an allergic response
produces very specific symptoms (swelling, irritation, shock)
a food intolerance may produce symptoms as diverse as sleepiness,
dizziness, anxiety, restlessness, gas, diarrhea or other discomfort.
In short, "intolerance" is can be used as a catch-all
to describe any negative reaction, while "allergy"
is a more specific medical term that describes an immune response
to an antigen.
Webmaster's note: With that said, I often
use the term "allergy" when describing my food intolerance
to others. It's a convenient shorthand and is accurate enough
for a simple social encounter. For situations that require
a more accurate description (for example, publishing an informational
website) I do my best to stay away from the term.