[JohnKemeny]

Note that there are theories that migraines start long before an actual attack, and that with this migraine comes certain cravings.

I'm other words, one might crave chocolate and coffee due to the migraine, and only later get symptoms, thereby causing us to believe that there's a causation.

Post hoc ergo propter hoc.

[balder1991]

I’ve read enough people say they went coffee free and it helped that I don’t think the craving thing holds up, but I can see it happening in a different symptom: some people say the trigger is like bright lights, but I actually think the upcoming headache may be the one causing the light sensitivity, which would lead us to “remember” the bright lights.