Hepatitis B, or viral hepatitis B, is a systemic infectious disease caused by the hepatitis B virus (HBV), with liver damage as the main cause. The main transmission routes include mother-to-child transmission, blood and body fluid transmission, and sexual transmission. Hepatitis B virus may be present in the blood, semen, saliva and breast milk of hepatitis B patients, but the content of hepatitis B virus is highest in blood and very low in saliva, so eating together and other behaviors generally do not lead to the transmission of hepatitis B. However, if the hepatitis B virus is actively replicating in the body of the hepatitis B patient who eats together, and the patient has mouth ulcers and bleeding gums, the risk of transmitting hepatitis B through eating together will increase. However, there is no need to overly panic because hepatitis B vaccination is a reliable way to prevent hepatitis B. The hepatitis B vaccination stimulates the body to produce hepatitis B surface antibodies, which protects the body from being infected by the hepatitis B virus. Therefore, if one of your close contacts, such as family members, has hepatitis B, it is recommended to check the hepatitis B two-to-one half. If the hepatitis B surface antibody is positive, it indicates that you have developed immunity to the hepatitis B virus and the risk of infection is extremely low; if the hepatitis B surface antibody is negative, it is recommended to get the hepatitis B vaccine in time to prevent infection. Therefore, hepatitis B is mainly transmitted through mother-to-child transmission, blood and body fluids transmission, and sexual transmission. Generally, eating together will not transmit hepatitis B. However, to prevent hepatitis B virus infection, early vaccination against hepatitis B is still recommended.