London: Certain types of mouthwash can kill off 'good' bacteria in the mouth, spiking blood pressure and increasing the risk of heart attacks and strokes, scientists, including one of Indian-origin, have warned.
Mouthwashes that contain the chemical chlorhexidine can raise blood pressure by killing off 'good' bacteria that help blood vessels relax, according to a study published in the journal Free Radical Biology And Medicine.
"Killing off all these bugs each day is a disaster when small rises in blood pressure have significant impact on morbidity and mortality from heart disease and stroke," said Professor Amrita Ahluwalia, of Queen Mary, University of London.
"We are not telling people to stop using antiseptic mouthwashes if they have a gum or tooth infection but we would ask why anyone else would want to," Ahluwalia said.
The study tracked the blood pressure of 19 healthy people who started using a mouthwash twice a day. The mouthwash contained 0.2 per cent by volume of the antiseptic chlorhexidine, 'The Daily Express' reported.
Their blood pressure shot up by between 2 and 3.5 units, the study found.
For each two-point rise in blood pressure, the risk of dying from heart disease rises by seven per cent and the risk of dying from stroke by 10 per cent, researchers said.
Chlorhexidine kills microbes needed to help create nitrite, which is essential for blood vessels to dilate properly.
The mouthwash caused nitrite-production in the mouth to fall by over 90 per cent and blood nitrite to fall by 25 per cent.
While not all mouthwashes contain chlorhexidine, Ahluwalia said other mouthwashes could still disrupt the healthy bacteria.
