Based on a review of the literature the authors discuss the role of nutrition in the precipitation of migraine and tension-type headache (TTH). The available information relies largely on the subjective assessment of the patients. Controlled trials suggest that alcohol and caffeine withdrawal are the most important nutritional precipitating factors of migraine and TTH. In addition, there is some evidence that missing meals is also an important factor. Dehydration seems to deserve more attention. A selective sensitivity to red wine has been shown in some patients, the importance of chocolate has been doubted seriously, and scientific evidence for cheese as a precipitating factor is lacking. Despite a series of experimental studies demonstrating that NO donors such as nitroglycerin and parenteral histamine cause headache the role of histamine, nitrates, and nitrites in food remains unclear. Similarly, other biogenic amines and aspartame have not been proven to precipitate headache. Sodium glutamate causes adverse reactions including headache probably at large doses ingested on an empty stomach. Therefore, patients should be advised that food plays a limited role as a precipitating factor of migraine and TTH. Subjective sensitivity to certain foods should be examined critically, and proven precipitating factors should be avoided. General dietary restrictions have not been proven to be useful.