Table 1. Excluded papers and reasons for exclusion.

Studies	Reason for exclusion
Abnet et al. 2001, Abnet et al. 2005a, Abnet et al. 2005b, Abnet et al. 2008, Ansai et al. 2013, Bundgaard et al. 1995, Divaris et al. 2010, Fernandez-Garrote et al. 2010a, Hiraki et al. 2008, Marshall et al. 1992, Stolzenberg et al. 2003, Talamini et al. 2000, Tu et al. 2007, Watabe et al. 1998, Wei et al. 2005, Zheng et al. 1990	No periodontitis but tooth loss
Ahn et al. 2012	Narrative review
Cabrera et al. 2005	Association between poor oral health and cardiovascular disease
Chang et al. 2016	Association between all periodontal diseases (including gingivitis) and pancreatic cancer
Demirer et al. 1990, Guha et al. 2007, Rosenquist et al. 2005, Sepehr et al. 2005, Talamini et al. 2000	Association between oral health in general and cancer
Hujoel et al. 2003	Association between periodontitis and mortality for cancer
Mai et al. 2015	Association between periodontal pathogens and cancer
Mai et al. 2016, Salazar et al. 2012, Soder et al. 2011, Tezal et al. 2005, Tezal et al. 2007	Unclear / No definition of periodontitis
Yen et al. 2014	Other association

^a No periodontitis but tooth loss and gingival bleeding