Objectives: This umbrella review summarizes the clinical evidence across meta-analyses regarding the association between periodontitis and systemic diseases. Methods: Seven databases were searched up to January 2018 for meta-analyses of human studies on the association between periodontitis and systemic diseases. Two independent authors performed in duplicate study selection, data extraction, and methodological assessment with the AMSTAR 2 tool. Data synthesis included random-effects meta-analyses of the cumulative evidence across papers using odds ratios or relative risks with their corresponding 95% confidence intervals. The robustness of each association was assessed according to existing epidemiological criteria. Results: The literature search yielded a total of 707 papers, from which 51 unique meta-analyses were included with most of them having serious methodological weaknesses according to the AMSTAR 2 tool. A wide variety of systemic conditions were statistically significantly associated (P<0.05) with periodontitis including among other: cancers (head-neck cancer, lung cancer, pancreatic cancer, and oral cancer), cardiovascular conditions (including coronary heart disease, arterial hypertension, carotid atherosclerosis, myocardial infarction and cardiovascular mortality), chronic kidney disease, erectile dysfunction, inflammatory bowel disease, metabolic syndrome, overweight/obesity, pregnancy-related adverse outcomes (gestational diabetes, pre-eclapsia, pre-term birth, low birth weight, and pre-term low-weight birth), respiratory conditions (chronic obstructive pulmonary disease, rheumatic diseases (including rheumatoid arthritis, ankylosing spondylitis, psoriasis, and systemic lupus erythematosus), and obstructive sleep apnea, with effects ranging from 1.13 to 4.57 (Figure). However, many identified associations suffered from residual confounding, statistical heterogeneity, bias related to their basic study design, discrepancies between the disease prevalence and incidence, and small-study effects. Therefore, less than half of the identified associations between periodontitis and systemic health were supported in the end by robust epidemiological evidence. Conclusions: Periodontitis seems to be associated with many diseases, which might have important repercussions for both disease prevention and treatment. Image(s): Download Image 1 Student Presenter Disclosure Statement: The submitter must disclose the names of the organizations with which any author have a relationship, the nature of the relationship, and the clinical or research area involved. The following is submitted: NONE