Matcha, the finely ground powder of green tea leaves, is a popular daily beverage. A concern for drinkers is its potential to cause teeth discoloration. Like all teas, matcha contains compounds that lead to extrinsic staining (surface discoloration on the enamel). However, staining is generally less severe than that associated with darker beverages such as coffee or black tea.
The Staining Culprits in Matcha
Teeth staining from matcha is rooted in specific plant compounds known as chromogens, which are color molecules. Matcha, a concentrated form of green tea, contains a significant amount of polyphenols, including tannins and catechins. These compounds bind to the pellicle, a thin protein film that constantly forms on the tooth enamel.
Tannins adhere to the tooth surface, making it easier for pigmented molecules to cause discoloration. The green color of matcha is due to its high content of chlorophyll, another chromogen. If not promptly removed, this green pigment can bind to plaque, leading to subtle discoloration.
The staining potential is also influenced by the fine, particulate nature of the powder. Because the entire tea leaf is consumed, the concentration of these pigments is higher compared to steeped green tea. While these compounds contribute to discoloration over time, the health of the tooth enamel plays a large part in how susceptible a person is to staining.
Comparing Matcha Staining to Common Beverages
Matcha’s staining effect is generally considered moderate when compared against other popular pigmented drinks. The primary reason it stains less than black tea or coffee is its substantially lower concentration of dark-colored tannins. Black tea, for example, undergoes an oxidation process that converts its lighter catechins into dark theaflavins and thearubigins, which are potent, dark-brown chromogens.
Coffee also contains high levels of dark chromogens and is often more acidic than matcha, which can temporarily soften the tooth enamel and make it more vulnerable to staining. While matcha can cause a subtle greenish or grayish hue on the teeth, the stains from coffee and black tea tend to be a more noticeable yellow or dark brown. Red wine, which is highly pigmented and very acidic, causes more immediate and severe discoloration than matcha. Switching to matcha from a daily habit of coffee or black tea can result in less surface staining.
Practical Steps to Prevent Teeth Staining
To enjoy matcha without compromising your smile, several steps can minimize its staining potential. The most effective action after finishing your matcha is to rinse your mouth thoroughly with plain water. Swishing water around helps wash away pigment molecules before they fully adhere to the enamel or the pellicle.
Another simple technique is to use a straw, especially when consuming iced matcha or matcha lattes. A straw can help bypass the front surfaces of the teeth, significantly reducing the contact time between the pigmented liquid and the enamel. It is also beneficial to consume your matcha relatively quickly rather than sipping it over a long period, which repeatedly exposes your teeth to the staining agents and acidity.
A common mistake is brushing immediately after consumption, which should be avoided. The polyphenols and any mild acidity in the drink can temporarily soften the outer layer of the enamel. Dentists recommend waiting a minimum of 30 minutes after drinking matcha before brushing your teeth. This waiting period allows your saliva to naturally remineralize and reharden the enamel, preventing abrasive brushing from causing damage.
Saliva is a natural defense against staining and decay because it helps neutralize acids and wash away particles. Stimulating saliva flow can be achieved by chewing sugar-free gum or eating fibrous foods like celery or apples after your drink. Maintaining excellent daily oral hygiene, including brushing twice a day with a fluoride toothpaste and flossing, is the foundational defense, as it removes the plaque that the chromogens primarily bind to.