Saliva (commonly known as saliva) is the key to food digestion, helps prevent tooth decay and infection, and ensures chewing and swallowing. Without saliva, the body cannot break down and digest food properly. Saliva is also one of the best health indicators. 1. Saliva measurement can detect many diseases. Saliva maintains the balance in the body, and once an imbalance occurs in the body, saliva will have a direct reflection. By testing a half-drop of eyedrop-sized saliva, doctors can reveal a series of biological secrets about the human body. British researchers have found that the measurement of a specific protein in saliva can assess a patient’s risk of heart disease. A saliva test developed by Keio University and the University of California in Japan can detect 99% of pancreatic cancers, 95% of breast cancers and 80% of oral cancers. 2.Saliva reflects stressful emotions. Once a person is stressed, salivary glands will secrete saliva alpha-amylase into the mouth. Through the measurement of this amylase, doctors can measure the stress produced by pregnant women to the fetus. Researchers explain that the imbalance of the stress hormone cortisol in saliva makes people very sensitive to stressful events. 3, saliva is six times more effective than morphine for pain relief. The British journal “Nature” published a French study found that saliva not only contains 72 different types of bacteria, but also contains a natural painkilling substance opiorphin, the analgesic effect of this substance is six times that of morphine, which helps prevent enkephalin pain signals from reaching the brain. 4, saliva secretion around the clock. Human saliva secretion 24 hours a day, from eating every bite of food to experience stressful events, salivary glands will increase secretion. A person secretes an average of 2 to 4 pints of saliva per day (about 1137 to 2273 ml). 5. Tension and stress are high and saliva secretion is low. A decrease in the quantity and quality of saliva is called “dry mouth syndrome”. This usually happens when you are nervous, upset or under a lot of stress. Frequent dry mouth can lead to difficulty eating, chewing, swallowing and even speaking. 6. Certain medications can cause a decrease in saliva. Thick saliva indicates that it is more difficult for the salivary glands to secrete saliva. Prescription and over-the-counter medications for allergies, pain or colds can cause dry mouth. These medications can alter the changes in water flow in and out of the cells and, if left untreated, can lead to tooth decay, gum disease and oral infections. 7, salivary glands also grow stones. Salivary gland stones (also called salivary stone disease) can occur in the salivary gland ducts or glands, and more than 90% occur in the submandibular gland. In addition to feeling dry mouth, patients may experience neck pain or difficulty swallowing. The exact mechanism of salivary gland calculi is not fully understood. It is generally believed that prolonged inflammation leads to the accumulation of minerals in the salivary glands and their calcification into stones.