Millions of people incorporate mouthwash into their daily hygiene routines, often believing it essential for fresh breath and cavity prevention. However, dental professionals are increasingly advising against its regular use, suggesting it is unnecessary for most and could potentially cause harm.
Researchers have found limited evidence that mouthwash is more effective than tooth brushing in preventing cavities or eliminating bad breath. Conversely, some studies have raised concerns that it may lead to elevated blood pressure and, in some cases, a higher risk of cancer.
Dentists recommend brushing teeth at least twice daily with fluoride toothpaste as the primary method for maintaining oral health. The physical action of brushing removes bacteria and food particles, while fluoride strengthens tooth enamel. The foam generated during brushing also helps fluoride adhere to teeth more effectively than when used in mouthwash.
Mouthwashes are broadly categorized into therapeutic and cosmetic types. Cosmetic mouthwashes offer temporary relief from bad breath and a pleasant taste but do not address underlying issues. Therapeutic mouthwashes contain active ingredients designed to kill bacteria and combat problems like gum disease and tooth decay. However, experts warn that these can disrupt the delicate balance of the oral microbiome.
The mouth harbors billions of bacteria, many of which are beneficial. Therapeutic mouthwashes can indiscriminately eliminate both harmful and beneficial bacteria. This disruption can have broader health implications, particularly concerning blood pressure regulation.
According to public health experts, oral bacteria play a role in managing blood pressure. They convert nitrates from food into nitrites, which are then transformed into nitric oxide, a compound crucial for dilating blood vessels and lowering blood pressure. When these bacteria are depleted by mouthwash, this process can be impaired.
Small studies have indicated a correlation between mouthwash use and changes in blood pressure. One trial involving healthy adults showed a significant reduction in blood pressure-regulating bacteria after a week of rinsing twice daily with a therapeutic mouthwash. Another study observed a slight increase in blood pressure and decreased nitrite levels in adults using mouthwash for seven days. A separate trial with individuals already experiencing high blood pressure found that three days of mouthwash use further elevated their blood pressure. These studies often involved mouthwashes containing chlorhexidine, a potent antiseptic typically recommended for short-term use.
Concerns also extend to potential links with heart disease, as high blood pressure is a known risk factor for cardiovascular problems. Additionally, some mouthwashes contain up to 27 percent alcohol. While alcohol helps kill bacteria, it is also a known carcinogen. A 2014 study linked mouthwash use to oral cancer, specifically in individuals using it more than three times daily.
Experts emphasize that mouthwash should not be seen as a substitute for treating the root cause of bad breath, which could be indicative of underlying dental issues like gum disease. Using mouthwash in such instances is akin to masking a symptom without addressing the problem.
While occasional use, such as once a week or month, is unlikely to cause significant harm, daily use over extended periods could lead to complications. Oral medicine experts suggest that while keeping mouthwash on hand is acceptable, daily application is not advisable for maintaining optimal oral and overall health.