|A new study found out that mouthwash use can significantly reduce the benefit of blood pressure-lowering physical exercise / Photo by Andriy Popov via 123RF|
Past studies have already shown that people with poor oral health, such as tooth loss and gum disease, are more at risk for cardiovascular problems, such as stroke and heart attack compared to people who practice good oral hygiene.
The link between heart disease and gum diseases
Harvard Medical School’s associate professor of medicine Robert H. Shmerling, MD published last year various theories on why poor oral health and cardiovascular diseases are connected. For instance, the bacteria that infect a person’s gums can lead to periodontitis or gingivitis can also travel to the blood vessels, as well as other parts of the body. Soon, it will lead to blood vessel inflammation, create tiny blood clots and damage, and stroke or heart attack may follow.
Mouthwash use vs. water: effects on physical exercise
A new study conducted by a team of scientists from the University of Plymouth in England also revealed a link between cardiovascular health and oral bacteria but in a completely different light. They found out that mouthwash use can significantly reduce the benefit of blood pressure-lowering physical exercise.
To come up with such a result, the team asked 23 healthy adults with no oral health conditions to run on a treadmill for half an hour and during two occasions. After which, they asked the subjects to rinse their mouth, either by using placebo water but mint-flavored and a real antibacterial mouthwash. Neither the participants nor the researchers knew which liquid the subjects were rinsing their mouth with at that particular time. The subjects were then monitored for two hours. Before and after running on a treadmill, the researchers measured the blood pressure of the participants and taken blood and saliva samples. During the participants’ recovery period after the exercise, no drink or food was allowed.
Result of the tests
The researchers discovered that the participants who rinsed with placebo showed a -5.2 mmHg reduction in their systolic blood pressure. The effect was only one hour after the physical exercise. On the other hand, participants who used mouthwash after the exercise had an average -2.0 mmHg reduction of their systolic BP.
In blood pressure readings, the systolic pressure is the top number that refers to the amount of pressure in the arteries during the contraction of the heart muscle. It is the level of blood pressure when the heart is pushing blood around the body.
Benefits of exercise diminished by over 60% and totally abolished after two hours
Because of the tests, the team realized that the blood pressure-lowering effect of the physical exercise was reduced by over 60% in the first hour of body recovery. Then, the effect would be erased two hours after the exercise when the subjects were already using the mouthwash.
Previous studies claimed that nitric oxide is formed in the cells (endothelial) that line our blood vessels during the physical exercise. However, the University of Plymouth research challenged those claims. This was because the result of their experiments showed that the level of blood nitrite did not increase after physical exercise when a mouthwash was used. There is only an increase in the nitrate levels in the blood when the participants used water to rinse their mouth after exercise. This showed that oral bacteria is the main source for such a molecule for at least the first period of body recovery.
Co-author Craig Cutler said that nitrite synthesis by the oral bacteria is necessary for kick-starting how the body will react to physical exercise, especially during the recovery period as it promotes muscle oxygenation and lowers the blood pressure. He continued that it is as if the oral bacteria open the blood vessels during the recovery period. If they are removed, the nitrite cannot be produced and so the blood vessels will just remain in their present state.
University of Plymouth’s lecturer in physiology and dietetics Dr. Raul Bescos, who is also the lead author of the study, further explained that the lowering of BP and blood flow supply to the leg muscles as a response to the physical exercise was impaired since the oral bacteria were not able to produce nitrite. Dr. Bescos added that a regular visit to the dentist is important for people who are at high cardiovascular health, such as those with hypertension, diabetes, and obesity. Nevertheless, he wanted people to avoid using an antibacterial mouthwash if not prescribed to treat an oral condition.
|The bacteria that infect a person’s gums can lead to periodontitis or gingivitis can also travel to the blood vessels / Photo by Anton Estrada via 123RF|
The study, which was published in the journal Free Radical Biology and Medicine, was made in collaboration with Spain-based Center of Genomic Regulation. The team shared that they will be doing a large study later on and one that will subject the clinical populations. That way, their findings will be more in-depth. They also believed that long-term study in the area they started will improve the public’s knowledge to efficiently treat high blood pressure.