Many of the causes of bitterness in the mouth are not serious, but if the symptoms are irritating, they may interfere with people’s daily diet. The main causes of a bitter mouth are related to dry mouth, oral diseases, pregnancy and certain diseases. Dry mouth symptoms can occur when the mouth does not produce enough saliva. Saliva in the mouth helps to reduce the bacteria in the mouth and when dry mouth is present, the increased bacteria in the mouth can lead to bitterness in the mouth. Poor oral hygiene can also lead to a bitter taste in the mouth, and a poorly sanitized mouth can lead to dental and periodontal problems. Infections, increased gum disease or gingivitis, etc. can also cause bitterness in the mouth. A bitter or metallic taste in the mouth can occur during the first trimester of pregnancy, when hormones in the body fluctuate during pregnancy. This can cause some foods or smells to look disgusting. Bitterness in the mouth can also be caused when the body is infected with a disease, most commonly a cold. When you have a cold, there is a problem with your sensory organs, and at this time, what you eat no longer tastes the same, and the sensation of taste is bitterness. There are many reasons for bitterness in the mouth, the most common being problems with the mouth, and if you want to know the exact cause you can seek the help of a professional doctor.