Periodontal disease is characterized by a low‐grade systemic inflammatory state that increases blood levels of proinflammatory cytokines, including tumor necrosis factor alpha and IL‐6, similar to obesity, suggesting a potential risk for nonalcoholic fatty liver disease in the bidirectional relationship between periodontal disease and obesity (see Section 4, Figure 2). This evidence concerns the gene TNF and obesity due to melanocortin 4 receptor deficiency.