Trigger Confusion

Hi.  I've had migraines for about four years now and until the past few months they were extremely predictable. They pretty much always felt the same, and while I never knew when one was coming or what would set one off I knew how to handle it.  But now all of a sudden things that never bothered me are all of a sudden causing me to get migraines, particularly sleep and soda.  Both triggers suddenly showed up about three months ago, probably within a week or two of each other.  I noticed the sleep problem first.  I used to be an 8-9 hours girl.  I can function on a few hours, but to be truly rested and feel good I need 8-9.  Now if I go any more than 6-7 I wake up with a horrible migraine and stabbing pain behind my right eye.  And I'm absolutely exhausted.  I feel like a zombie.
     However, my main confusion is with food triggers.  Ever since I've had these headaches, each doctor I've had has tried to figure out a food trigger and we've never been able to find one, even with food diaries.  Then out of nowhere, about three months ago I had a Pepsi with lunch one day and within twenty minutes had a pretty intense headache across the whole front of my forehead.  It wasn't quite a usual migraine for me, but it really got my attention, and I had some pretty intense light sensitivity my whole way home that night.  The next day the same thing happened, and every time I've had a caffeinated brown soda ever since.  However, that same first week I decided to do an experiment and went and got a coffee.  I didn't get a headache from it then or after. In fact, coffee seems to help my migrianes sometimes.  I don't understand the difference.  At this moment I am trying another little experiment and drinking a caffeine free rootbeer.  It's been over an hour since I started, and so far so good.  I don't know if there's something in the caffeinated sodas.  The only different ingredient between two rootbeers I've found (one caffeinated and one not) was something called acacia, and I have no idea what that is.  I really just don't understand why that would become a trigger so suddenly, what would change in my body/brain.  I drank soda fairly frequently, not everyday but often enough that this was a shock.  I guess I just don't understand how these things can just change so suddenly and at the same time.  It just seems like overnight, like a switch was flicked somewhere.

[DrNoopurMD]

Hi,

Thanks for writing in.
It is important to realize that migraines change in character and intensity over a period of time. The triggers also keep changing. The exact reason is not understood till now.
Soft drink contains caffeine which is a definite migraine trigger. Coffee also contains caffeine but is sometimes found to relieve migraines. This is just a short term effect and is due to the fact that it contains caffeine in amounts sufficient to constrict blood vessels in the brain and relieve migraine.
Hope this helps.