not sure that there are ones that are worse when you already have a migraine, but there are ones that are common triggers for people that will give them one. Keep in mind not everyone reacts the same

The commonest foods which can cause difficulty (but sometimes what affects one person is fine for another) include

* peanuts and peanut butter
* caffeine in all products, not just coffee
* dairy products
* yeast
* some beans (which includes peanut), as well as broad, lima, Italian, lentil, soy, peas
* avocados
* dried meats
* sauerkraut
* pickled herrings
* canned soups and packet soup mixes
* chicken livers
* ripe banana
* soya products as well as the bean itself
* sodium nitrate, which is used to preserve hot dogs, bacon and cured meats
* the preservative benzoic acid and its associated compounds
* MSG, common name for monosodium glutamate, a flavor enhancer which is now in almost universal use in almost all processed foods
* nuts
* sourdough breads
* cheeses which have been aged, i.e. cheddar
* red wines, beer, champagne, vermouth
* chocolate
* anchovies

gave this some thought... the reason i can't think of any foods to avoid during a migraine is because i do not eat and barely drink during a migraine