Migraine sufferers have a different mix of gut bacteria that could make them more sensitive to certain foods, scientists have found.
The study offers a potential explanation for why some people are more susceptible to debilitating headaches and why some foods appear to act as triggers for migraines.
The research showed that migraine sufferers had higher levels of bacteria that are known to be involved in processing nitrates, which are typically found in processed meats, leafy vegetables, and some wines.
The latest findings raise the possibility that migraines could be triggered when nitrates in food are broken down more efficiently, causing vessels in the brain and scalp to dilate.
Antonio Gonzalez, a programmer analyst at the University of California San Diego and the study’s first author, said: “There is this idea out there that certain foods trigger migraines; chocolate, wine and especially foods containing nitrates. We thought that perhaps there are connections between what people are eating, their microbiomes and their experiences with migraines.”
Dr. Brendan Davies, a consultant neurologist at the University Hospitals of North Midlands and a trustee of the Migraine Trust, said the idea of gut bacteria playing a role in a migraine was medically plausible.
The study, published this past Tuesday in the journal mSystems, sequenced bacteria found in 172 oral samples and 1,996 fecal samples from healthy participants, who had also reported whether they were affected by migraines.
In both oral and fecal samples, people with migraines had slightly higher levels of bacteria linked to breaking down nitrates.
Around one in seven people suffer from migraines, with the majority having an attack more than once a month and about half being severely affected when they get a migraine.
Chocolate is sometimes cited as a migraine trigger, but previous research suggests that often people crave sweet food during a preparatory phase of a migraine before symptoms have started.
The scientists are now planning a controlled diet study of migraine sufferers to see whether nitric oxide levels in the bloodstream are linked to migraine attacks.
In the future, the researchers said, it might be possible to “Have a magical probiotic mouthwash” that would alter the balance of bacteria to help prevent migraines.
For now “If you suspect that nitrates are causing your migraines, you should try to avoid them in your diet,” said Gonzalez.