If you suffer from migraine, you might be having significantly more bacteria in your mouth than usual, says a study published by mSystems.
Migraines hurt like hell— says (mostly) every sufferer of the throbbing headaches. What causes them, one might ask. A theory states that migraines might be the result of the type of food consumed. Researchers from University of California San Diego School of Medicine, the authors of the new study, therefore, set out to investigate the link (if any) between the two.
“There is this idea out there that certain foods trigger migraines—chocolate, wine and especially foods containing nitrates,” says study first author, Antonio Gonzalez. “We thought that perhaps there are connections between what people are eating, their microbiomes and their experiences with migraines.”
What do nitrates have in special? When consumed (they are found in foods like leafy vegetables), they are subjected to a number of processes that change them into other compounds, and here is where mouth bacteria come into play. Microbes in the mouth turn nitrates into nitrites which can then be converted into nitric oxide under specific conditions. Nitric oxide is not all that harmful. It can, instead, enhance blood flow, thereby decreasing blood pressure. However, it can come with unpleasant side effects: previous studies show that cardiac patients taking drugs with some levels of nitrates will often experience severe headaches. Furthermore, many who suffer from migraines have reported that they consume nitrates.
To shed light on possible associations between the variables, Gonzalez and his team analysed and sequenced bacteria from 172 oral samples and 1,996 fecal samples. This revealed different amounts of bacterial species in people who get migraines and those who don’t. Digging further, the researchers found that, relative to the bacterial species present, genes encoding for enzymes dealing with nitrate, nitrite, and nitric oxide were significantly more abundant in the oral samples of migraineurs.
“We know for a fact that nitrate-reducing bacteria are found in the oral cavity,” said co-author, Embriette 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.”
Now, the team looks forward to categorising migraineurs themselves, in terms of the different types of migraineurs, to find out whether their oral bacteria actually express the nitrate-reducing genes, and if there is any real correlation between this and migraines.