Many people use mouthwash every day to keep their mouth fresh and clean. It’s known for killing germs, fighting bad breath, and helping to prevent gum disease. But recent studies suggest that mouthwash might be doing more than we thought—and not all of it is good.
Some scientists now believe that mouthwash could have an effect on your blood pressure. At first, this idea might sound strange. After all, what does a mouth rinse have to do with the heart or blood pressure? But when we look more closely at how the body works, the connection starts to make sense.
Blood pressure is the pressure of your blood against the walls of your blood vessels. It’s an important sign of health. If your blood pressure is too high—called hypertension—it can raise your risk of serious health problems like heart disease and stroke.
Researchers have studied many things that can affect blood pressure, such as salt in your food, how much you exercise, how stressed you are, and even your sleep. But they’ve also been paying attention to the body’s microbiome—the many tiny bacteria that live in and on our bodies, including in the mouth.
Some of the bacteria in your mouth are actually helpful. One important job they do is helping your body make a chemical called nitric oxide. Nitric oxide helps relax and widen your blood vessels, which makes it easier for your blood to flow and helps keep your blood pressure down.
Here’s how the process works: When you eat foods high in nitrates—like spinach or beetroot—these nitrates get turned into nitrites by the bacteria in your mouth. Then, the nitrites are turned into nitric oxide in your body. Without those mouth bacteria, the process breaks down.
This is where mouthwash becomes a problem. While mouthwash is great at killing harmful germs, it doesn’t choose which bacteria to kill. It wipes out both the bad and the good bacteria—including the ones that help turn nitrates into nitrites. When this happens, your body might not make enough nitric oxide, and your blood pressure could rise.
A study in the journal Free Radical Biology and Medicine found that people who used mouthwash twice a day had a noticeable rise in their blood pressure in just one week. Another study in the Journal of Blood Pressure found that people who used mouthwash regularly over a longer period also had higher blood pressure than those who didn’t.
These findings don’t mean that mouthwash is dangerous or that no one should use it. Keeping your mouth clean is very important for your health, and mouthwash can be helpful for many people, especially those with gum disease. But if you already have high blood pressure—or are trying to avoid it—it may be worth thinking about how often you use mouthwash.
It’s a good reminder that everything in the body is connected. Sometimes, something we use for one part of our health can have unexpected effects elsewhere. That doesn’t mean we have to stop using helpful products like mouthwash—but it does mean we should use them wisely.
So next time you swish and spit, take a moment to think not just about your teeth and gums, but also about your overall health. If you’re unsure what’s best for you, it’s always a good idea to talk to your doctor or dentist. They can help you find the right balance between keeping your mouth healthy and protecting your heart too.
If you care about high blood pressure, please read studies that early time-restricted eating could help improve blood pressure, and natural coconut sugar could help reduce blood pressure and artery stiffness.
For more health information, please see recent studies about added sugar in your diet linked to higher blood pressure, and results showing vitamin D could improve blood pressure in people with diabetes.
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