By Joy Stephenson-Laws, JD, Founder

One of the great benefits of exercise is that it may help reduce blood pressure. Many Americans exercise in order to reap this benefit. 

But did you know that the bacteria in our mouths may play a role in whether we experience the blood pressure-lowering benefits of exercise? 

Just like our guts, our mouths are home to many different types of bacteria. There are more than 700 different types of bacteria in the human mouth! And, of course, we want to rid our mouths of the bacteria that may give us bad breath or, even worse, gingivitis. We obviously want to keep the bacteria that may be beneficial to us.

Now it appears that some mouthwashes will deplete the oral cavity of bacteria that helps us reap the blood pressure-lowering benefits of exercise. 

(I previously blogged about how some mouthwashes may destroy beneficial bacteria in the mouth and increase the risk of obesity and diabetes by altering blood sugar metabolism).

And now a recent study suggests that “...the blood pressure-lowering effect of exercise is significantly reduced when people rinse their mouths with antibacterial mouthwash, rather than water—showing the importance of oral bacteria in cardiovascular health,” according to this report discussing the study.

When we exercise, our blood vessels open up because the cells produce nitric oxide, which increases the diameter of the blood vessels (a process known as vasodilation). This increases blood flow circulation to active muscles. 

"What has remained a mystery is how blood circulation remains higher after exercise, in turn triggering a blood-pressure lowering response known as post-exercise hypotension,” said one of the lead authors of the study.

"Previous research has suggested that nitric oxide was not involved in this post-exercise response—and only involved during exercise—but the new study challenges these views.”

Nitric oxide breaks down into nitrate, and nitrate can be absorbed by the salivary glands and excreted with saliva in the mouth.

In addition to this, “Some species of bacteria in the mouth can use nitrate and convert into nitrite—a very important molecule that can enhance the production of nitric oxide in the body. And when nitrite in saliva is swallowed, part of this molecule is rapidly absorbed into the circulation and reduced back to nitric oxide. This helps to maintain a widening of blood vessels which leads to a sustained lowering of blood pressure after exercise,” said the lead author of the study.

The goal of the study was to see if using mouthwash would take away oral bacteria that is possibly responsible for the nitrate to nitrite conversion that helps prolong blood pressure-lowering effects after a person is done exercising.

Researchers took 23 healthy adults and asked them to run on a treadmill for 30 minutes during two separate occasions. After each run, participants were monitored for two hours. After each running event, participants were asked to either rinse their mouths with antibacterial mouthwash or just a mint flavored water (the placebo). Participants were asked to rinse one, 30, 60 and 90 minutes after their runs.

Blood pressure was measured and saliva and blood samples were taken into account before the participants exercised and 120 minutes after they exercised. Only water (no food or other beverages) was allowed both before and after exercise. Also note that none of the participants had oral health issues.

What did the results reveal?

The results showed that “...the blood pressure-lowering effect of exercise was diminished by more than 60% over the first hour of recovery, and totally abolished two hours after exercise when participants were given the antibacterial mouthwash.”

This is a pretty big deal if you are someone who is battling hypertension or is at a high risk of developing hypertension.

So does this mean you should kick your mouthwash to the curb?

It’s tricky, because like with most things surrounding your health, there is no one-size-fits-all approach. If you are otherwise healthy and don’t have any existing metabolic issues, like hypertension or diabetes, then mouthwash is probably fine for you. 

But if you are overweight, diabetic, or have high blood pressure, then perhaps mouthwash may not be the best for you. So the best thing you can do is talk to both your dentist and a competent healthcare professional about your concerns.

Obviously, the bigger message here is the importance of having control over our health. There are many external factors that may raise our blood pressure or prevent it from being lowered, but if we are otherwise healthy we may have less risk. 

Finally, never forget the importance of a healthy, nutrient-rich diet when it comes to maintaining a healthy blood pressure. Click here to learn about supplements you may want to look into, specific foods and nutrients best for blood pressure and foods to avoid.

And yes, your blood pressure can be too low!

Enjoy your healthy life!

The pH professional health care team includes recognized experts from a variety of health care and related disciplines, including physicians, attorneys, nutritionists, nurses and certified fitness instructors. This team also includes the members of the pH Medical Advisory Board, which constantly monitors all pH programs, products and services. To learn more about the pH Medical Advisory Board, click here.