Association Between Inflammatory Diet and Oral Diseases: Results from the 2015-2018 National Health and Nutrition Examination Survey

Abstract

The link between sugar consumption and oral health is well-established, yet the role of inflammation in this relationship has been underexplored. This study investigates the association between the energy-adjusted Dietary Inflammatory Index (E-DII) and various oral health outcomes using data from the 2015–2018 National Health and Nutrition Examination Survey (NHANES). The analysis included 8,131 U.S. adults aged 20 years or older, all of whom had completed dental examinations and two-day dietary recalls, representing a weighted population of approximately 231 million individuals. E-DII was categorized into quartiles, with higher scores indicating a more pro-inflammatory diet. Several potential confounders were adjusted for including age, race, gender, education, income, and smoking status. The distribution of E-DII quartiles was significantly associated with various demographic factors, with lower education and income levels correlating with higher E-DII scores. More than one-third of non-Hispanic Black adults (34.4%) were in the highest E-DII quartile, whereas 43.2% of non-Hispanic Asians were in the lowest quartile. Additionally, a higher proportion of current smokers and individuals with limited dental visits were in the highest E-DII quartile. Oral health outcomes included untreated coronal and root caries, missing teeth, and complete edentulism. Logistic and Poisson regression models were used to assess the association between E-DII quartiles and these outcomes, controlling for the potential confounders. Higher E-DII quartiles were significantly associated with poorer oral health outcomes. Individuals in the highest E-DII quartile had greater odds of experiencing coronal caries (OR: 2.17, 95% CI: 1.62–2.91), root caries (OR: 2.10, 95% CI: 1.37–3.22), and missing teeth (OR: 1.53, 95% CI: 1.13–2.06), compared to those in the lowest quartile. The mean number of decayed teeth also increased progressively with higher E-DII quartiles (adjusted mean ratio for Q4: 1.79, 95% CI: 1.29–2.47), as shown by Poisson regression. Sensitivity analyses, including a modified E-DII excluding carbohydrates and alcohol, confirmed these associations. Further analysis using a binary classification of E-DII and continuous modeling supported the relationship between pro-inflammatory diets and poor oral health. Each unit increase in continuous E-DII was associated with increased odds of coronal caries (OR: 1.30, 95% CI: 1.16–1.44) and missing teeth (OR: 1.16, 95% CI: 1.05–1.27).

The results of this study highlight the significant impact of pro-inflammatory diets on oral health outcomes. A higher E-DII, which indicates a more inflammatory diet, was consistently associated with worse oral health, including greater odds of coronal and root caries, missing teeth, and a higher number of decayed teeth. These findings suggest that dietary adjustments could serve as a potential strategy to prevent oral diseases and improve overall oral health.