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Fitness & Health

05th Sep 2019

Using mouthwash could reduce the benefits of working out, study says

According to scientists, the blood pressure-lowering effect of exercise is reduced when you rinse your mouth with antibacterial mouthwash, rather than water

Alex Roberts


Freshening up after your gym session is essential, but don’t overdo it

Excessive mouthwash use could blunt the positive effects of exercise. The headline might surprise you, but there’s logic behind it.

How do you explain the results? Exercise reduces your blood pressure, which is why your doctor will always tell you to stay active. However, for you to make the most out of your workout, you need a certain level of bacteria present in the body – your mouth included.

According to scientists at the University of Plymouth, the blood pressure-lowering effect of exercise is significantly reduced when you rinse your mouth out with antibacterial mouthwash, rather than water.

This study shows the importance of oral bacteria to heart health.

Why excessive mouthwash use blunts the benefits of exercise

As part of the study, 23 healthy adults were asked to run on a treadmill for a total of 30 minutes on two separate occasions, after which they were monitored for two hours.

On each occasion, they rinsed their mouths out after training with either mint-flavoured water or antibacterial mouthwash.

These rinses were done one minute after working out, and then again at 30, 60 and 90 minutes after. Participants did not know whether they were rinsing with the water or mouthwash.

Their blood pressure was measured and saliva and blood samples were taken before and after exercise.

What did the evidence show?

For people given antibacterial mouthwash, the blood pressure-lowering effect of exercise was lower by more than 60% in the first hour after training, and totally abolished two hours after exercise.

What the scientists say

Craig Cutler, study co-author, said: “In effect, it’s like oral bacteria are the ‘key’ to opening up the blood vessels. If they are removed, nitrite can’t be produced and the vessels remain in their current state.

“Existing studies show that, exercise aside, antibacterial mouthwash can actually raise blood pressure under resting conditions, so this study followed up and showed the mouthwash impact on the effects of exercise.”

The difference between good and bad bacteria

Remember, not all bacteria is bad. Your body needs a degree of bacteria present. When you’ve got an infection and take antibiotics to clear it, you often feel unwell for a period afterwards. This is because the antibiotics have absolutely wiped your body of all bacteria. It’s a scattergun approach that works for curing illness, but for long term health and longevity, you need healthy bacteria too.

This is definitely the case when it comes to your oral health.

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