Chocolate is often cited as a trigger for headaches and also Migraines. Research points to a combination of ingredients in Chocolate that may cause an attack. Cocoa and Caffeine are key ingredients in chocolate and have potential to irritate or change the excitability of the central nervous system. Also Chocolate often contains high levels of sugars, which can interfere with normal blood sugar level regulation, leading to secretion of the hormones that affect blood vessels in and around the head and face.
Other Top suspects according to the National Headache Foundation in the US in 2013 (applies to Australia)
Most common Food Triggers according to National Headache Foundation (US)
Note: Other foods can also act as triggers, so best to keep a diary of foods before an attack.
• Ripened cheeses (such as cheddar, Emmentaler, Stilton, Brie, and Camembert)
• Marinated, pickled, or fermented food
• Foods that contain nitrites or nitrates (bacon, hot dogs) or MSG (soy sauce, meat tenderizers, seasoned salt)
• Sour cream
• Nuts, peanut butter
• Sourdough bread
• Broad beans, lima beans, fava beans, snow peas
• Figs, raisins, papayas, avocados, red plums
• Citrus fruits
• Excessive amounts (more than 2 cups total) of caffeinated beverages such as tea, coffee, or cola
• Alcohol (including red wine and beer)
This list represents a number of food types/classes.