This study aimed to explore the association between dietary inflammatory potential and tooth loss due to dental disease. The results showed that participants in the most pro-inflammatory diet group (DII quintile 5) had a significantly greater mean number of teeth lost compared to those in the most anti-inflammatory diet group (DII quintile 1). This trend was consistently observed in both the 40–59 and ≥60 age groups. These findings suggest that a higher dietary inflammatory potential is associated with an increased risk of tooth loss in middle-aged and older adults.

Beta-carotene, vitamin E, and vitamin D-all known for their anti-inflammatory properties-were consistently consumed at inadequate levels across all DII quintiles (Q1-Q5), which contributed to elevated DII scores <Fig. 1>. Beta-carotene, a carotenoid and natural pigment found in numerous fruits and vegetables, is recognized for its ability to modulate systemic inflammatory responses, which can be ascribed to its antioxidant and anti-inflammatory properties. A significant decrease in serum C-reactive protein levels has been observed in individuals following a diet rich in beta-carotene [16]. Vitamin E is found in a variety of plant-based foods, including cooking oils, almonds, spinach, and broccoli. It is acknowledged as one of the most essential fat-soluble antioxidants that contribute to the maintenance of homeostasis within the body [17]. A meta-analysis suggests that α-tocopherol is the most bioactive form of vitamin E. Additionally, a daily supplementation of 500 mg or more has been statistically associated with an average reduction in C-reactive protein levels of 0.52 mg/L [18]. Although the exact mechanism by which vitamin D operates is not fully understood, current research suggests that it has a variety of regulatory effects on both the innate and adaptive immune systems [19]. Research has demonstrated that elevated inflammation associated with insufficient magnesium intake has been observed across various tertiles. A retrospective cohort study conducted among U.S. adults identified a relationship between low magnesium consumption and elevated levels of inflammatory markers, including high-sensitivity C-reactive protein, which is implicated in the development of systemic inflammation and metabolic disorders [20]. Moreover, heightened inflammation levels linked to insufficient zinc intake were observed across various quintiles <Fig. 1>. Zinc is essential for the regulation of cellular proliferation and differentiation, and the immune system, which relies heavily on effective cellular proliferation, is particularly susceptible to zinc deficiencies [21]. The DII is predicated on the hypothesis that six inflammatory biomarkers present in the bloodstream-specifically IL-1β, IL-4, IL-6, IL-10, TNF-α, and C-reactive protein-exhibit interconnections [4]. This interrelationship suggests that chronic systemic inflammation, which may result from a diet deficient in anti-inflammatory components, could contribute to the incidence of tooth loss.

By categorizing the DII into quintiles and analyzing the contribution of individual dietary components, we found that the increase in DII was primarily attributable to the inadequate intake of anti-inflammatory nutrients <Fig. 1>. Inadequate management of systemic inflammation via a suitable anti-inflammatory diet may compromise immune responses to periodontopathogenic bacteria, thereby increasing the likelihood of tooth loss. Middle-aged Americans, particularly those aged 45 to 64 years, demonstrate the highest prevalence of severe periodontitis and are at a heightened risk for tooth loss [22]. Periodontitis has the potential to induce systemic inflammation via various mechanisms. Instances encompass the hematogenous dissemination of periodontal pathogens and inflammatory mediators, in addition to the systemic migration of activated lymphocytes [23]. This form of persistent low-grade inflammation is acknowledged as a significant contributor to the onset of several metabolic disorders. Type 2 diabetes mellitus, which is characterized by the development of insulin resistance, adversely affects the cellular repair mechanisms that respond to damage inflicted by subgingival bacteria. This dysfunction is linked to increased concentrations of inflammatory cytokines, such as interleukin-1β and interleukin-6, in addition to elevated levels of C-reactive protein, a marker indicative of acute-phase inflammation. Consequently, the persistent accumulation of low-grade chronic inflammation may ultimately result in the loss of teeth [24]. Furthermore, visceral fat, which plays a crucial role in the development of abdominal obesity, secretes inflammatory adipokines such as tumor necrosis factor-α and interleukin-6 [25]. These molecules are recognized for their ability to disturb metabolic equilibrium and intensify low-grade chronic inflammation. Tooth loss is commonly noted among individuals exhibiting abdominal obesity [26], indicating that chronic inflammation associated with metabolic dysregulation may intensify periodontal inflammation, thereby contributing to the loss of teeth. The mitigation and management of systemic inflammation are essential for the prevention of metabolic disorders and the reduction of the likelihood of tooth loss. Consequently, adhering to an anti-inflammatory diet is crucial for reducing systemic inflammation and preserving metabolic equilibrium.

Research indicates that around 21% of American adults between the ages of 20 and 64 have untreated dental caries [27], whereas a significant 96% of individuals aged 65 and older have encountered dental caries at some point in their lives [28]. Tooth loss attributable to dental disease, as delineated in this research, encompasses loss resulting from dental caries, which may possess limited efficacy as a mediator of systemic inflammation. By analyzing the diverse characteristics of anti-inflammatory foods, it is possible to ascertain their potential advantages. The dietary component exhibiting the lowest consumption within the quintile of the DII was dietary fiber <Fig. 1>. Dietary fiberis present in whole grains, vegetables, and fruits, promotes the self-cleaning effect in the oral cavity and provides various micronutrients essential for maintaining oral health. Research conducted on adults in the United States has identified a relationship between insufficient dietary fiber consumption and a heightened risk of dental caries [29]. Consequently, it is imperative to prioritize sufficient fiber consumption as a means of enhancing dietary practices aimed at preventing tooth loss.

This study’s strengths include the use of nationally representative data, which ensures external validity through post-stratification adjustments and survey weighting. Moreover, subgroup analyses considering age-related differences in tooth loss were conducted, enabling more detailed and robust findings through complex statistical approaches. Despite these strengths, this study has certain limitations. First, the DII assesses the inflammatory potential of nutrients but does not fully capture dietary patterns, including food types and processing levels. Further analysis considering these factors is needed. Second, this research employed only 28 out of the 45 available items to compute the DII, thereby constraining the interpretation of the findings. Third, a two-day period of 24-hour dietary recall may not provide a comprehensive representation of an individual’s overall dietary consumption. Nevertheless, by omitting participants whose dietary consumption may have been affected and implementing a weighting adjustment that accounted for the day of the week and non-response (WTDR2D), we improved the robustness of our results. Fourth, tooth loss due to other causes was not considered in this study. Subsequent research should incorporate a more comprehensive array of factors that influence tooth loss. Fifth, this research is grounded in data from the U.S., its findings may have limited generalizability to the dietary patterns and cultural characteristics specific to Korea. Nonetheless, the principal benefit of employing U.S. data lies in its representation of a wide range of ethnicities, dietary practices, and cultural contexts. This diversity facilitates a more comprehensive assessment of the hypothesis concerning the association between dietary inflammation and tooth loss. Future research endeavors should include data from Korea. Furthermore, by conducting comparative analyses of the findings from this study alongside data from both the United States and Korea, researchers will be able to evaluate the influence of ethnic and cultural variables on the association between anti-inflammatory dietary consumption and tooth loss attributable to dental disease.