This is a common question clinically.
Especially in people who are left with no answer after having had MRI's, CT's, etc that ruled out the big, scary things.
A recent study in 2017 with 115 children ages 3-15 suffering from chronic primary headaches revealed some very reliable connections to food and additive triggers.
Through an elimination of a group of foods. 87% percent received resolution of headaches by elimination of 1-3 of these foods.
Caffeine was the most common implicated trigger , then in order of frequency: monosodium glutamate, cocoa, aspartame, cheese , citrus and nitrites . One patient reported sensitivity to tomatoes.
Realize that some patients needed to eliminate 3 of these food items to reach resolution and others only 1. They eliminated these foods for up to 6 weeks.
Not surprising to me as many of these foods are vasoactive through histamine release. Meaning they can cause micro changes in circulation which is often thought to be the migraine mechanism.