The metabolic syndrome (also known as syndrome X, insulin resistance syndrome, dysmetabolic syndrome, deadly quartet and plurimetabolic syndrome) is a cluster of factors associated with increased risk of developing coronary heart disease and/or type 2 diabetes. Several recent studies reviewed in the present paper have indicated an association between the metabolic syndrome and periodontitis, and suggest that people exhibiting several components of metabolic syndrome should be encouraged to undergo a periodontal examination. Further investigations are required to clarify the mechanisms of the relationship between metabolic syndrome and periodontal disease in men, and to determine whether oral health care in individuals exhibiting metabolic syndrome has the potential to reduce the incidence of various systemic diseases.