Over 34% of the mouthwash products might stain the teeth
【譯文】Many people will use mouthwash in addition to brushing their teeth in the morning and evening, but have you ever thought that mouthwash with problematic ingredients may cause more and more stains and even temporarily affect your sense of taste? The Consumer Council of Hong Kong tested 32 types of mouthwash available in Hong Kong and found that 11 products (about 34%) contained "cetylpyridinium chloride" or "chlorhexidine", which may cause stains on the teeth and temporarily affect the sense of taste with long-term. Some people have to stop using them for two or three days to regain their sense of taste. The Consumer Council also cited information from the World Health Organization that the alcohol concentration should be as high as 60% to 80% to kill bacteria effectively. The alcohol concentration of mouthwash is far from enough to kill the bacteria. There are ten products with lower fluoride content than toothpaste, so the effectiveness of tooth decay prevention is questionable. The Consumer Council stresses that mouthwash is not the more "spicy", the more effective, the public should not rely on mouthwash; proper brushing and flossing are more effective.
The Consumer Council pointed out in the latest issue of its monthly magazine "CHOICE" that it searched for 32 types of mouthwash in the market in October this year and found that the labelling information of all the samples was unsatisfactory, including the lack of clear instructions on the amount and frequency of daily use and the age of application, etc. More than 30% of the samples (i.e. ten models) were only in Japanese or did not list the mouthwash ingredients. The Consumer Council pointed out that some of the active ingredients of mouthwash have side effects, as well as not suitable for some people to use, and manufacturers have the responsibility to disclose in detail to facilitate consumer selection.
Ten products were found to contain "Cetylpyridinium chloride" (CPC), and one had "Chlorhexidine". Both ingredients help reduce bacteria in the mouth. Still, long-term use may stain teeth, affect the appearance and even temporarily jeopardise the sense of taste, and some people need to stop using the product for two or three days to regain the sense of taste.
At the same time, one product contains "povidone-iodine". The Consumer Council said that this ingredient is commonly used in disinfectants for disinfecting the skin. This ingredient can help reduce the risk of viral and bacterial infections of the mouth and throat. However, since povidone iodine releases free iodine in the process of action, it is not recommended for use by pregnant women or people with thyroid disorders. Also, povidone-iodine may discolour dentures and braces, so it is recommended that dentures and braces be removed before rinsing.
The Consumer Council found that nearly half of the samples contained alcohol in this evaluation. The Consumer Council explained that some mouthwash ingredients are difficult to dissolve in water, so manufacturers will add alcohol as an auxiliary solvent to help mix the different ingredients in the formula to make it taste "smoother". Although alcohol is also a commonly used disinfectant, according to the World Health Organization guidelines, the concentration of alcohol needs to reach 60% to 80% to kill bacteria and viruses effectively. Still, the alcohol content in mouthwash generally does not reach this concentration, so the use of mouthwash containing alcohol does not necessarily have a better bactericidal effect.
In addition, ten samples were labelled as containing fluoride, which helps prevent tooth decay, but the content was much lower than that of ordinary toothpaste. The chairman of the Consumer Council's Publicity and Community Relations Group, Mr Siu King-wai, pointed out, "The plaque attached to the surface of the teeth can only be removed by toothbrush and dental floss, and mouthwash cannot thoroughly and effectively penetrate the plaque, so mouthwash can only be used as an auxiliary product for oral care, and needs to be combined with good cleaning habits to achieve the desired effect."
Many consumers have the myth that the spicier the mouthwash, the more effective. The Consumer Council said that the irritation of mouthwash is not directly related to bactericidal effectiveness. As for eliminating bad breath, some mouthwashes add zinc salt to cover bad breath, but users ignore the real cause of bad breath. In addition, some mouthwash claim to have the function of whitening teeth, adding less than 2% of hydrogen oxide, the concentration is much lower than the dentist whitening treatment, and the effectiveness is also doubtful. The Consumer Council stressed that mouthwash could not replace daily brushing and urged the public not to let children under six years old use mouthwash.◆ 琬琰