We know that some foods can be migraine triggers for some people. It differs from one person to the next. Some people have migraines that can be triggered by several foods or beverages while some of us have no food or beverage triggers. We also have known for some time that certain foods such as hot dogs, lunch meats, other preserved foods, and leafy green vegetables can be triggers because of the nitrates in them. What we don't know is exactly why nitrates can trigger migraine attacks.
Study results published in mSystems, the journal of the American Society for Microbiology suggest that certain bacteria found in the mouths of people with migraine may be responsible for nitrates being a migraine trigger. People who experience migraine attacks have more of this bacteria in their mouths than people who do not experience migraine attacks. The bacteria reduces nitrates to nitrite, which increases levels of nitric oxide. Higher levels of nitric oxide have been related to migraine in other research.
The study authors concluded:
"These results show for the first time a potential link between bacterial nitrate, nitrite, and nitric oxide reducers and migraines, by reporting their higher abundances in the oral cavities of people with migraines than in the oral cavities of those who do not suffer from migraines. Future studies should focus on further characterizing the connection between oral bacterial nitrate, nitrite, and nitric oxide reducers and migraines."
In a CNN interview, Embriette Hyde, Ph.D., assistant project scientist at the University of California, San Diego School of Medicine and a coauthor of the study, said:
"One can imagine a targeted treatment, such as mouthwash or the introduction of a probiotic species. However, this will be really complex. It's certainly a complicated puzzle."
"While the link between migraines and nitrates has been known for a while, researchers still aren't sure about the nature of this link. We know it depends on eventual formation of nitric oxide, but the exact mechanism hasn't been established yet. This study is very preliminary, and while the findings are exciting, we need to confirm them in a larger, targeted cohort."
William B. Young, MD, a migraine and headache specialist at the Jefferson Headache Center, also commented in the CNN interview, saying:
"You're not just the person you are, you're also, medically speaking, the bugs that live in your gastrointestinal system, and that could play a part in a lot of medical diseases and possibly, according to the study, migraine. The problem with the study is correlation is not causation. It could well be other reasons why people with migraine have different gut bacteria."
Comments and implications for patients:
While the information from this study is interesting, it is very preliminary. As Dr. Young noted in his comments, the study shows a correlation between migraine and an increased amount of certain bacteria in the mouths of migraineurs, but it doesn't prove the bacteria to be the cause for foods containing nitrates to be migraine triggers.
This study has no immediate implications for patients. If future research shows the bacteria to indeed be a cause in nitrates triggering migraine, the long-term implications could be the development of a treatment to reduce the amount of bacteria and counteract the effect of nitrates in triggering migraine.
More helpful articles:
Managing Migraine — Migraine Trigger Foods
Migraine and Food Choices
Gonzalez A, Hyde E, Sangwan N, et al. Migraines Are Correlated with Higher Levels of Nitrate-, Nitrite-, and Nitric Oxide-Reducing Oral Microbes in the American Gut Project Cohort. mSystems. 2016;1(5):
Howard, Jacqueline. How your mouth is linked to your migraines. CNN.com. October 20, 2016.