Mouthwash could reduce the benefits of exercise

USING antibacterial mouthwash could reduce the benefits of exercise, a study has found.

Physical exertion is known to lower blood pressure, but the effects are significantly reduced when people use mouthwash instead of water.

A team of international scientists said the results showed the importance of oral bacteria in cardiovascular health.

The study was led by the University of Plymouth in collaboration with the Centre of Genomic Regulation in Barcelona.

Researchers asked 23 healthy adults to run on a treadmill for 30 minutes on two separate occasions, after which they were monitored for two hours.

At one, 30, 60 and 90 minutes after exercise they were asked to rinse their mouths – either with antibacterial mouthwash or a placebo of mint-flavoured water.

Their blood pressure was measured and saliva and blood samples were taken before exercise and at 120 minutes after exercise.

The study found that when participants rinsed with the placebo, the average reduction in systolic blood pressure was minus 5.2mmhg at one hour after.

When participants rinsed with the antibacterial mouthwash, the average systolic blood pressure was minus 2mmhg at the same time point.

The results show the blood pressurelowering effect of exercise was diminished by more than 60 per cent over the first hour of recovery, and totally eradicated two hours after exercise when participants were given the mouthwash.

Dr Raul Bescos, the lead author from the University of Plymouth, said: “Scientists already know that blood vessels open up during exercise.

“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.”