Most of us do not think twice before gargling our mouth with oral antibacterial mouthwash solution to ensure that our breath stays fresh throughout the day. However, this seemingly harmless practice could take a serious toll on your vascular and heart health in the long run.
“Mouthwash is generally prescribed — and often used — as part of the daily oral hygiene routine along with brushing and flossing. In addition, most over-the-counter mouthwash have antibacterial ingredients such as alcohol and cetylperidinium chloride,” shares Prof Dr Kaumudi Joshipura, Dean, School of Public Health, Ahmedabad University and Adjunct Faculty, Harvard TH Chan School of Public Health, Boston, in an email interaction with Happiest Health. Cetylperidinium chloride is an ammonium-based compound used in some mouthwashes, toothpaste, breath sprays and the like.
Research using the San Juan Overweight Adults Longitudinal Study (SOALS) has proven that prolonged use of mouthwash more than twice a day for over a year increases the risk of developing hypertension by 85 per cent as compared to those using mouthwash less frequently. These people also have twice the risk of hypertension than those who never used mouthwash. The study also suggests that people often use over-the-counter mouthwash with fluoride and anti-bacterial agents longer than prescription mouthwash with chlorohexidine.
How mouthwash can negate the benefits of a healthy diet
In the mouth, benign oral microbes convert dietary nitrates into nitrites and then to nitric oxide, to be absorbed by the body. Nitric oxide is your body’s natural blood pressure regulator that keeps your heart healthy. Antibacterial mouthwash can completely kill these oral microbes.
“This process is an essential part of nitric oxide metabolism. It is only conducted by oral bacteria and not gut bacteria. Hence, frequent mouthwash use reduces nitric oxide production and levels in the body,” Prof Dr Joshipura explains.
Green leafy vegetables have high nitrate content that is converted into nitric oxide after consumption. Hence, they are considered good for heart health. So, it could be said that daily mouthwash usage ends up negating the benefits of a healthy vegetarian diet.
“Most mouthwash has antibacterial constituents and is likely to have a detrimental impact on nitric oxide production, which could increase hypertension and cardiac risk,” Prof Joshipura adds.
Oral microbe and hypertension regulation link
“The vascular endothelium lining our arteries can produce nitric oxide but it is mostly broken down by the oral bacteria from nitrate-rich food. This doesn’t happen in the gut — it is mostly done by the oral microbes,” Dr Sunil Dwivedi, consultant, cardiology, Manipal Hospitals, Millers Road, Bengaluru, explains.
Dr Dwivedi adds that nitric oxide dilates the arteries and blood vessels. It also plays a major role in regulating your blood pressure and ensuring smooth blood circulation in your body.
Mouthwash increases the risk of hypertension
The researchers used SOALS to find the link between mouthwash and hypertension. The basis of their study and baseline observations were recorded in 2011. Subsequent follow-up processes were completed in 2016. Out of the 1351 participants included in the study, 630 were excluded due to medical reasons including pre-existing hypertension and diabetes. Another 176 did not complete the follow-up procedure and data collected from five more were found to be incomplete.
The study concluded that using antibacterial mouthwash increased the risk of hypertension by 85 per cent. Interestingly, this was consistent even among the non-smokers, indicating that the findings were independent of such factors. The findings were published in the peer-reviewed journal Blood Pressure in May 2020.
Prof Dr Joshipura explains, “Mouthwash with chlorohexidine should generally be prescribed only for a couple of weeks. However, people use over-the-counter mouthwash for months or even years. Fluoride also has some antibacterial properties and should have similar but perhaps weaker effects. Fluoride mouthwash also should generally be prescribed for two weeks at a time, although people tend to use it longer.”
Are mouthwash users also at high diabetes risk?
Prof Dr Joshipura and her team also carried out another study, in which they concluded that over-the-counter antiseptic mouthwash could also lead to an increased risk of diabetes. This indirectly suggests that oral nitrate metabolism and nitric oxide may play a role in diabetes.
“Low levels of nitric oxide are associated with inflammation, which could lead to increased glucose intolerance, insulin resistance and a higher risk of diabetes. Nitric oxide has also been associated with endothelial dysfunction,” she adds.
“However, the direct evidence relating nitric oxide and diabetes is very limited. While evidence does link nitric oxide with hypertension and cardiovascular conditions, its role in diabetes is controversial. It can both increase as well as inhibit insulin secretion, depending on its source and concentration,” Prof Dr Joshipura says.
Experts point out that unnecessary usage of antibacterial mouthwash should be regulated to ensure that beneficial oral microbes are retained.
Takeaways
- Antibacterial mouthwash will kill benign oral bacteria in saliva that metabolise dietary nitrate into nitrite and nitric oxide.
- As nitric oxide is a natural regulator of blood pressure, destroying the bacteria leads to a dip in its level. This considerably increases the risk of hypertension and heart health.
- People using over-the-counter mouthwash twice a day or more for over two years have 85 per cent more risk of developing hypertension.
