1. Overnight tea helps stop bleeding. Overnight tea contains acid, which can promote blood clotting. If oral bleeding occurs, you can drink overnight tea to rinse your mouth. If the skin bleeds, you can also use overnight tea to cleanse. 2. Eye-improving effect In addition to acid, overnight tea also contains tea polyphenols, and tea polyphenols have anti-inflammatory effects. If you have red eyes, you can use overnight tea to cleanse it, which will have a good effect. 3. Clean and strengthen teeth. The fluorine in overnight tea will calcify with the enamel of teeth, and after calcification, it will strengthen the resistance of teeth to acidic substances and prevent tooth decay. In addition, fluoride can also remove dental plaque. It is recommended to take a sip of overnight tea to rinse your mouth two or three minutes after a meal. Therefore, chewing gum is not as good as rinsing with tea to clean your teeth. 4. Eliminate bad breath. Overnight tea contains essential oils and is fragrant. If you use tea to rinse your mouth regularly, it can help eliminate bad breath. Bad breath is a headache and it is easier to feel embarrassed in social places. Try to rinse your mouth with tea.