Suffering from migraine headaches?

Better check what's in your mouth.

This is a little convoluted, so take it slowly. Drugs that contain nitrates promise severe headaches as a side effect. Pharamcists create nitrate-containing drugs primarily for people with cardiovascular issues as nitric oxide can aid cardiovascular health by improving blood flow and reducing blood pressure. Nitrites in your system get converted into nitric oxide while circulating in your bloodstream under the right conditions. And leafy green vegetables and certain processed meats get reduced into nitrites by bacteria found in your mouth.

Research from the University of California San Diego School of Medicine supports the notion that the mouths of migraine sufferers harbor significantly more microbes with the ability to modify nitrates than people who do not get migraine headaches.

“There is this idea out there that certain foods trigger migraines — chocolate, wine and especially foods containing nitrates,” said first author Antonio Gonzalez. “We thought that perhaps there are connections between what people are eating, their microbiomes and their experiences with migraines.”

Gonzalez and colleague Embriette Hyde, PhD, used publicly available data from the American Gut Project, a crowd-funded citizen science effort. They sequenced bacteria found in 172 oral samples and 1,996 fecal samples from healthy participants. Previously, the participants had indicated whether they suffered from migraines.

The researchers noticed that bacterial species were found in different volumes between people who get migraines and those who do not. And it was just the bacteria in the mouth that mattered: no significant differences in either fecal or oral samples were discovered between the migraine sufferers and the non-migraine group.

“We know for a fact that nitrate-reducing bacteria are found in the oral cavity,” said Hyde. “We definitely think this pathway is advantageous to cardiovascular health. We now also have a potential connection to migraines, though it remains to be seen whether these bacteria are a cause or result of migraines, or are indirectly linked in some other way.”

The next steps for Gonzalez and Hyde include reaching out to a more defined group of patients, delineated by the types of migraines they normally suffer from. They then can determine whether their oral microbes actually express those nitrate-reducing genes, measure their levels of circulating nitric oxide, and determine how they correlate with migraine status.

The research was published in mSystems, a magazine distributed by theAmerican Society for Microbiology.