Research is increasingly pointing towards the importance of the gut-brain axis in regulating our health. Not only has the health of our gut bacteria, or microbiome, been linked to neurodegenerative diseases such as Parkinson’s and Alzheimer’s disease, it has also been linked to mental health conditions such as depression and anxiety, and autoimmune disorder multiple sclerosis. Now, on top of this, it seems to influence migraines too.
In a study from 2016, researchers found that people who have migraines tend to have more bacteria, particularly in the mouth, that emits nitric oxide. A known trigger for migraines, this finding may offer an explanation as to why migraines occur more frequently in some rather than others, and how certain foods may trigger them in the first place.
In the study, Antoni Gonzalez from the University of California San Diego and his team used high-throughput RNA sequencing technology to analyze bacteria from 172 oral samples and 1,996 fecal samples from healthy participants both with and without a history of migraines. They ultimately found that those who suffered from migraines tend to have higher amounts of bacteria that produce nitrates than those who do not suffer from them.
These findings correspond with another study conducted in 2019 in which researchers found a link between probiotic usage and migraines. For the study, they recruited 50 people either suffering from chronic or episodic varities of the headache. Receiving either a placebo or a probiotic containing 14 strains of bacteria including Bacillus subtilis and Lactobacillus, they found that after 8-10 weeks of usage, those on probiotics saw significant decreases in migraine attacks than those on placebos.
In total, the frequency of migraines fell by 45% for those with chronic migraines, and 40% for those with the episodic variety. Moreover, those with chronic migraines saw the intensity of their headaches drop by 31%, while those with episodic migraines saw an average drop of 29%.
Suggestive findings, headache specialist at the National Migraine Center, Katy Munroe, believes that there is therefore most likely a link between migraines and the microbiome health. However, due to small sample sizes, further research is needed before conclusions can be made that this link is more than just a correlation.