How Your Mouth, Mouthwash, and Headaches Affect Each Other
Two areas of health that you probably wouldn’t expect to be related are oral health and migraines. What could be the connection between oral hygiene and the number and intensity of migraine attacks you get on a regular basis?
Actually, there is some scientific evidence which suggests that there is a link between bacteria in your digestive tract—including your mouth—and head pain.
Nitrates, Nitrites, and Migraines, Oh My!
The article quotes study author Antonio Gonzalez as explaining, “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.”
Here is how it works:
Your mouth and gut contain bacteria that break nitrates down.
When the nitrates are broken down, they turn into nitric oxide.
Nitric oxide appears to be involved in migraine. Consider this intriguing paper titled, “A nitric oxide donor (nitroglycerin) triggers genuine migraine attacks.”
Researchers wanted to know if they could trigger migraine attacks by using nitroglycerin, which is a nitric oxide donor.
Taking measurements of middle cerebral artery blood velocity using transcranial Doppler as well as noting patients’ reports of symptoms, the researchers noted the following:
“Headache occurred during the nitroglycerin infusion as previously described but peak headache intensity did first occur 5.5 h after infusion. At this time the induced headaches in 8 of 10 completing patients fulfilled the diagnostic criteria for migraine without aura of the International Headache Society. Furthermore, all patients who normally had unilateral spontaneous migraine attacks also had unilateral headaches after nitroglycerin. Only one subject developed migraine after placebo (p < 0.03). The time pattern of headache and estimated middle cerebral artery dilatation corresponded well. The study therefore demonstrates that activation of the nitric oxide cGMP pathway may cause typical migraine attacks.”
It also appears that patients with migraine may be more sensitive to the effects of nitric oxide altogether.
In this study, researchers in a double-blind study tried giving four different doses of nitroglycerin to 17 control participants who didn’t have headaches, 17 patients with migraines, and 17 patients with tension-type headaches. They reported:
“The nitroglycerin-induced headache was significantly more severe in migraine sufferers, lasted longer, and fulfilled diagnostic criteria for migraine more often. Previous reports have shown a similar supersensitivity to histamine, which in human cerebral arteries activates endothelial H₁ receptors and causes endothelial production of nitric oxide. Migraine patients are thus supersensitive to exogenous nitric oxide from nitroglycerin and to endothelially produced nitric oxide. Nitric oxide may be partially or completely responsible for migraine pain.”
You’ll notice these studies were rather small. The study that The Guardian reported on was much larger. It was a cohort study, so the researchers were able to take a look at 1,996 fecal samples and 172 oral samples. Some of the participants had migraines and some did not.
There were elevated levels of nitrate-breaking-down bacteria present in the participants who had migraines. These elevated levels showed up in both types of samples.
So, we can hypothesize based on these study results as well as anecdotal reports concerning nitroglycerin and migraine sufferers:
- There are higher levels of nitrate-converting bacteria present in the mouths and digestive tracts of patients who have migraines.
- Patients with migraines may be extra-sensitive to the negative effects of nitric oxide.
So, that is a double hit. As a person with migraines, you may have more nitric oxide in your body than a healthy control, thanks in part perhaps to your higher bacteria levels. And then just to top it off, you may be supersensitive to the painful effects of said nitric oxide.
Key Point: Some research suggests that people with migraine headaches may have more bacteria which convert nitrates into nitric oxide (including in the mouth). They also may be supersensitive to nitric oxide’s effects.
Can Mouthwash Help Treat Migraines?
This leads to a highly hypothetical question. Could the right mouthwash bring pain relief?
The Guardian article states, “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.”
Obviously, we do not yet have a magical probiotic mouthwash that is being targeted at migraine sufferers.
But you might be wondering, “What about regular mouthwash from the store?”
I investigated this pretty thoroughly in the hopes of giving it a try. The idea of being able to disrupt this pathway via my mouth seemed pretty appealing.
This study investigated the “effects of a commercially available chlorhexidine-containing antibacterial mouthwash.” It concluded the following:
“Rinsing the mouth with the antibacterial mouthwash prior to the nitrate load had no effect on nitrate accumulation in saliva or plasma but abolished its conversion to nitrite in saliva and markedly attenuated the rise in plasma nitrite. We conclude that the acute increase in plasma nitrite seen after a nitrate load is critically dependent on nitrate reduction in the oral cavity by commensal bacteria. The removal of these bacteria with an antibacterial mouthwash will very likely attenuate the NO-dependent biological effects of dietary nitrate.”
This would seem to suggest that rinsing with such a mouthwash would help to mitigate any migraine-related effects tied to an excess of nitric oxide conversion from nitrate-containing food.
After quite a bit of digging, I found a study which was specific about the types of mouthwash investigated—and which compared several alternatives.
The effects of these four substances were compared:
- Water (control)
- Listerine antiseptic mouthwash
- Chlorhexidine (prescription-only, from what I can tell)
- Cepacol antibacterial mouthwash
Beet juice was the nitrate-rich substance that was consumed prior to gargling.
The effects of Listerine antiseptic mouthwash were found to be comparable to the water (control).
The researchers further reported, “Use of chlorhexidine and antibacterial rinses eliminated the beneficial effects of nitrate dosing on [blood pressure] BP. Chlorhexidine almost completely eliminated any nitrate-nitrite conversion.”
Take special note of the reference to blood pressure.
Some people load up on nitrates on purpose in an attempt to reduce blood pressure.
You can see that certain mouthwashes can counteract those efforts.
This is something which many people are unaware of when making oral care decisions.
Here is an excerpt providing further insights differentiating the effects of the chlorhexidine vs. the Cepacol antibacterial mouthwash:
“Conversely, the antibacterial mouthwash treatment partially inhibited the response (z220 nM increase from baseline) and Chlorhexidine almost completely eliminated any conversion (z60 nM increase from baseline). This is also logical, given that Cetylpyridinium chloride (in Cepacol ®) and Chlorhexidine both target the negatively charged bacterial membrane walls to cause disruption and cell death (both causing some brown staining of the teeth). The Chlorhexidine mouthwash also appears to have a greater concentration of the active chemical. Previous studies using a single mild chlorhexidine-based treatment mouthwash treatment (Corsodyl) in an acute dose  and for 7 days consecutively  showed a similar plasma nitrite response.”
This seems to be a relatively new area of research, so more studies are needed to be conclusive about the effects of various kinds of mouthwash on both nitric oxide levels and blood pressure.
And to my knowledge, nobody has studied mouthwash and migraine headaches.
Key Point: While there does not seem to be any research at all on a mouthwash and migraine headaches specifically, there is some research which shows that Chlorhexidine and Cepacol may kill nitrate-converting bacteria in the mouth.
After reading this study, I went to the store and picked up some Cepacol.
I have no blood pressure concerns, and it seemed worth a try since the worst-case result would simply be rinsing out my teeth and gums a bit.
For a couple of months, I have been rinsing with this stuff once a day. Though admittedly, I have skipped days, so it has not been the most consistent trial.
Have I had any results?
The jury is still out, particularly given my inconsistency. But at this point, I do not think I have had any improvements in my head pain which correlate with the mouthwash.
There could be any number of possible explanations for why it doesn’t seem to be doing any good.
Regardless, it is merely an anecdote, and not even a conclusive one at that. But hey, at least I don’t have bad breath, right?
Key Point: Can using the right type of mouthwash help combat severe headaches? I have no idea based on my experience.
What Foods Contain Nitrates?
One thing you can theoretically do for yourself as a migraine sufferer is try not to overindulge in foods which contain nitrates in the first place.
If you do not feed these nitrates to the bacteria in your body, they will not have those extra resources to break down into additional nitric oxide.
Here are some foods which are high in nitrate content:
- Certain cured and processed meats
- Dark chocolate
- Beets and beet juice
- Argula lettuce
- Bok choy
… Of course. Wouldn’t you just expect a list of healthy foods like this?
I’m definitely not suggesting you avoid anything on this list—just moderate these high-nitrate foods.
Actually, with the cured meats, look at the packaging before you buy. You can actually find meats that do not contain this high nitrate content.
As for the other things on this list, clearly you don’t want to give up on healthy vegetables like these, but if you eat them in moderation and put more of an emphasis on veggies which are lower in nitrates (and there are plenty of them) that could be one way to balance out your diet a bit.
I will also mention at this point that researchers still are not certain whether foods like chocolate and wine which are traditionally considered to be migraine triggers for some patients really are triggers.
It is possible that experiencing pain during or after eating such foods could simply be symptomatic of already being in the early stages of a migraine attack. This is an idea which has been gaining more traction lately.
Or, perhaps something can be both a trigger and a symptom.
More research is needed in this area.
Key Point: If you want, you can try moderating your intake of nitrate-rich foods and beverages.
Mind Your Blood Pressure
A word of caution if you have high blood pressure. As we talked about, nitric oxide plays a role in keeping blood pressure down. So, if you do manage to decrease your nitric oxide levels, your blood pressure can increase.
This certainly isn’t something you should mess around with. So if you have any concerns about your blood pressure, talk to a healthcare provider before reducing nitrates in your diet or using a mouthwash which might reduce nitric oxide production in your body.
Key Point: It is vital to support healthy blood pressure. Take that into account when making decisions about nitrates.
Conclusion: Mouthwash for Migraines is an Intriguing Prospect, But Research is Required
As a medical condition, migraines can very stubbornly resist treatment, particularly when they are chronic.
There does seem to be some interesting new research coming to light which could point towards the nitric oxide channel as a means for combating head pain.
Maybe someday there will be a “magical mouthwash” for migraines.
But as of right now, what we really need is more research into nitrates, nitric oxide, oral health and migraines.