willacethis wrote:
Hi experts,
Can you please help me in understanding why option A, which says that a delay/difficulty in associating a headache with a food allergy, weakens the conclusion "Obviously, some other cause of migraine headaches besides food allergies must exist".
The premise states that "putting patients on diets that eliminate those foods to which the patients have been demonstrated to have allergic migraine reactions frequently does not stop headaches".
Referring to the bold part, if we are eliminating ONLY those foods that do cause an allergic reaction, why do we even care about the duration of allergic response or how difficult it is to "observe links between specific foods patients eat and headaches they develop" as per option A?
To illustrate my point, if we have demonstrated that food B led to migraine and then removed food B from the patient's diet, why do we care about how difficult it was to identify that food B led to migraine? Shouldn't the migraine just stop had food B (or any other food item, the link of which is demonstrated) been the sole cause of the migraine?
Thanks!
The diets in the passage only eliminate foods which have been
demonstrated to cause allergic migraine reactions. These diets were unsuccessful in stopping the patients' migraines, so the author concludes that "some other cause of migraine headaches besides food allergies must exist."
In making this argument, the author is assuming that the only foods that
actually cause migraines have been clearly
demonstrated to cause migraines.
Consider this example: maybe a certain patient gets migraines every time she eats Flaming Hot Cheetos. So, she goes on a diet that eliminates Flaming Hot Cheetos -- but her migraines don't stop! From this, we might be able to conclude that the Cheetos are not the sole cause of her migraines.
But can we say that
all food allergies have been ruled out as the cause? Let's say the patient also eats cucumbers on a regular basis. She is allergic to cucumbers, but doesn't realize this because it take several days for an allergic reaction to appear. By the time she gets a migraine the link to the cucumber is very difficult to observe, as stated in (A).
Cucumbers have not been
demonstrated to give the patient migraines, so she does not eliminate them from her diet. The author's conclusion is now severely weakened, because her migraines are, in fact, caused by a food allergy -- just not the one the patient knew about.
(A) is the correct answer.
I hope that helps!
I want to make sure I eliminated option C by the right reasoning. Could you help me with that?
My thinking is - we don't learn anything new from option C to understand how migraine headaches are caused by factors other than food allergies. If these people (mentioned in option C) stop having these foods and migraine headaches don't stop then we are back to the same question what is causing headaches besides food allergies? Hence, we can't proceed with this option and our confidence doesn't change.