A Scientist has warned Listerine may increase the risk of two deadly cancers and that people should not be using it every day. Daily gargling of the Cool Mint flavour was found to increase the level of two bacteria in the mouth in a recent study.
Both bacteria have previously been linked to oesophageal and bowel cancer.
It is believed that the alcohol in the mouthwash interferes with the normal level of bacteria in the mouth.
After three months of Listerine use, two species of bacteria – Fusobacterium nucleatum and Streptococcus anginosus – were found to be at much higher levels.
Scientists from the Institute of Tropical Medicine in Antwerp, Belgium, also saw a decrease in a group of bacteria called Actinobacteria, which have previously been found to contribute to the regulation of blood pressure.
Professor Chris Kenyon, a scientist at the university who worked on the study, told The Telegraph that using the mouthwash “could increase their risk of cancer and various infections”.
He also claimed: “Most people should not be using it and if they do use it, they should use the preparations without alcohol and limit the use to a couple of days.”
Prof Kenyon and his colleagues discovered during an investigation into the impact of daily mouthwash use on STI risk among gay men when they made the finding.
The 59 participants used Listerine every day for three months followed by three months of placebo mouthwash or vice versa.
While the experiment only included Listerine, Prof Kenyon said that similar levels of bacteria would likely be found using other alcohol-based mouthwashes.
Listerine Cool Mint is 20 per cent alcohol but alcohol-free mouthwash alternatives are available in most high street pharmacies and are recommended by the scientists of the latest study.
