Some researchers suggested that salivary microbiota may contribute to systemic metabolic changes, with specific oral bacteria potentially promoting insulin resistance by increasing tumor necrosis factor (TNF)-α and lipopolysaccharide levels or decreasing adiponectin levels, thereby altering energy expenditure and further influencing obesity (Coker et al., 2022). This evidence concerns the gene TNF and obesity due to melanocortin 4 receptor deficiency.