Periodontitis is the most common oral disease. It is a chronic disease that is characterised by the destruction of the tissues. It is caused by multifactorial aetiology. Variation in host metabolism and microbes results in the development of periodontitis. Saliva provides us with a protective role of lubrication, neutralizing the pH, mineralising the bones and fighting microbes in a diseased oral cavity. We need to identify metabolites in saliva to know the aetiology and stage of periodontitis. Some metabolites may help in the diagnosis and treatment of periodontitis. Various classes of the biochemicals like amino acids, lipids, carbohydrates, nuclear peptides, dipeptides are changed in periodontitis. Most importantly, there is an increase in the levels of protease, glycosidase and lipase activity in chronic periodontal disease that forms the most favourable time for the growth of bacteria. There is a deficiency in contempered screening methods. Therefore, we should understand the arising need for metabolites for better diagnosis and treatment of periodontitis.