Breath mints are small candies that are designed to give your breath a refreshing feeling and pleasant scent. The key ingredients in most breath mints are menthol, peppermint oil, and various artificial flavors. When you place a breath mint in your mouth, the menthol and peppermint oil create a cooling sensation by triggering the cold-sensitive receptors in the mucous membranes of your mouth and nose. This gives you the feeling that your mouth and throat have been chilled. But does this cooling sensation mean that breath mints actually lower the temperature in your mouth?
How menthol and peppermint oil create a cooling sensation
The cooling effect of breath mints is an example of chemesthesis, which refers to the chemical sensitivity of the nerve endings in your mouth, nose, and throat. The key compound responsible for the cooling sensation is menthol, which is found naturally in mint plants. Peppermint oil, which is extracted from peppermint leaves, contains high concentrations of menthol.
When you put a breath mint in your mouth, the menthol activates the cold-sensitive TRPM8 receptors in your oral mucosa. The TRPM8 receptors are ion channels that are responsive to cold temperatures below 23°C. However, menthol and other chemical agents like mint oil can also activate these receptors, fooling your body into thinking the area is cold. This triggers the sensation of coldness without actually lowering the temperature in your mouth.
In addition to menthol, some breath mints contain other cooling agents like menthone and menthyl esters. These compounds provide an additional cooling effect by activating other cold-sensitive receptors.
Other effects of breath mints on your mouth
In addition to simply activating cold receptors, menthol and peppermint oil can also:
- Stimulate production of more saliva, which provides a wetting sensation
- Cause a slight anesthetic effect, making your mouth feel numb
- Trigger the release of serotonin and dopamine in the brain, leading to a pleasant, refreshing feeling
The combination of increased saliva, numbness, and neurotransmitter release enhances the cooling sensation and provides breath mints their refreshing quality. However, none of these effects actually lower the temperature inside your oral cavity.
Do breath mints reduce mouth temperature?
Given how convincingly breath mints simulate a cold sensation, you may wonder if they lower mouth temperature at all. However, research indicates that breath mints do not actually cool the inside of your mouth or throat.
In one study, researchers measured oral cavity temperature after dissolving breath mints in the mouth. They tested both pure peppermint oil mints and mints with peppermint oil plus menthol. The results showed that neither type of breath mint reduced oral cavity temperature compared to baseline measurements or plain water. The cooling sensation was purely due to chemical stimulation of cold receptors, not reduced temperature.
Table showing effect of breath mints on oral cavity temperature
| Treatment | Oral Cavity Temperature (°C) |
|---|---|
| Baseline | 36.8 |
| Water | 36.7 |
| Peppermint oil mint | 36.8 |
| Peppermint + Menthol mint | 36.9 |
As shown in the table, neither type of breath mint decreased oral cavity temperature compared to water or baseline. The cooling sensation was not accompanied by an actual drop in temperature inside the mouth.
How long does the cooling effect of breath mints last?
The cooling sensation from breath mints starts to feel noticeable around 3-5 minutes after placing the mint in your mouth. The intensity of the cooling peaks around 10 minutes later. However, the exact duration of the effect can vary based on the strength of the mint.
Most breath mints contain 1-3 milligrams of menthol or peppermint oil. Stronger mints may contain up to 10 mg. The higher the menthol concentration, the longer the cooling effect will last. Here is a rough timeline of how long the cooling sensation persists at different menthol doses:
- 1 mg menthol – Cooling lasts around 20 minutes
- 2 mg menthol – Cooling lasts around 30 minutes
- 5 mg menthol – Cooling lasts around 45 minutes
- 10 mg menthol – Cooling lasts around 60 minutes
Keep in mind that individual sensitivity can also impact duration. Some people may perceive the cooling for shorter or longer periods based on the density of cold receptors in their mouth.
Do breath mints cool your entire mouth?
The cooling effect of breath mints is usually most intense under the tongue and along the throat. However, menthol does stimulate receptors throughout the mucous membranes of the mouth, so the sensation spreads to the tongue, gums, cheeks, and palate as well. The mint flavor is often strongest in the back of the throat.
For maximum coverage, it’s best to allow the breath mint to completely dissolve and coat all areas of the mouth. Chewing or crushing the mint means some of the menthol will be swallowed faster, reducing duration.
Conclusion
In summary, while breath mints provide a strong cooling sensation in the mouth and throat, this is primarily caused by menthol chemically activating cold receptors. Breath mints do not actually lower the temperature inside the oral cavity. However, the cooling effect can persist for 20-60 minutes depending on the strength of the mint, providing fresh, cold relief. Just keep in mind that the chill is simply a perceptual effect, not a true drop in mouth temperature.
Other FAQs about Breath Mints
Do breath mints kill germs in your mouth?
Breath mints have very limited ability to kill germs or bacteria in the mouth. The main antimicrobial ingredients in some breath mints are essential oils like thymol and eucalyptol. However, these are present in very low concentrations in most commercial mints, not enough to provide substantial antibacterial activity. While essential oils can inhibit a few types of oral bacteria in lab tests, breath mints rely more on masking odors through their minty scent rather than actively destroying pathogens or germs.
How long do breath mints take to work?
You’ll start tasting the strong mint flavor of most breath mints within 1-2 minutes of placing them in your mouth. However, peak fresh breath usually isn’t reached until around 10-15 minutes after letting the mint dissolve. This allows time for the essential oils and flavoring to spread through the mouth and throat, masking odors as saliva production increases. To give breath mints enough time to work, avoid eating or drinking for at least 15-20 minutes after using one.
Do breath mints dehydrate your mouth?
Breath mints do not significantly dehydrate the mouth. In fact, mints containing menthol can stimulate more saliva production due to the cooling sensation and minty flavor. The increased saliva helps keep the mouth from drying out. Breath mints also contain other ingredients like sugar alcohols that help retain moisture. So while very spicy or highly concentrated mints could potentially cause slight temporary dryness, overall breath mints either hydrate the mouth or have a neutral effect.
Can breath mints damage tooth enamel?
When used in moderation, breath mints do not pose a high risk for tooth enamel erosion. However, very frequent consumption of highly acidic mints, especially chewing on them continuously, could potentially damage enamel over time. To minimize any risk, rinse your mouth with plain water after eating breath mints to neutralize any lingering acids from the candy.
Do breath mints help with bad breath?
Breath mints can temporarily mask bad breath by releasing minty scents and flavors that override unpleasant odors. However, they do not address the source of bad breath, which is usually tongue/mouth bacteria or periodontal disease. While helpful on occasion, relying solely on breath mints to treat chronic bad breath is not effective. See your dentist to identify the underlying cause. Proper oral hygiene and treatments to reduce bacteria and inflammation work better for lasting relief.