Association of dietary and plasma fatty acids with periodontitis: Results from the 2009-2014 National Health and Nutrition Examination Survey and Mendelian randomization study.

Background: The authors aimed to explore the association of fatty acids with periodontitis and its severity and to assess causality using Mendelian randomization (MR) analyses.

Methods: Data for participants with complete data were extracted from the 2009-2014 National Health and Nutrition Examination Survey. Weighted logistic regression was used to explore the relationship between dietary fatty acids and periodontitis and its severity. Univariable and multivariable MR analyses were performed to explore the causal association between plasma fatty acids and periodontitis.

Results: Two types of saturated fatty acids (hexadecanoic C16:0, octadecanoic C18:0) and monounsaturated fatty acids (hexadecenoic C16:1, docosenoic C22:1) and 3 types of polyunsaturated fatty acids (eicosatetraenoic C20:4, eicosapentaenoic C20:5, docosahexaenoic C22:6) were positively associated with periodontitis. Conversely, octadecadienoic (C18:2, a type of polyunsaturated fatty acid), total polyunsaturated fatty acids, and omega-6 fatty acids were negatively associated with periodontitis. Similar association patterns were also found between these fatty acids and the severity of periodontitis. Results of MR analyses revealed that no significant association was found between plasma fatty acids and periodontitis.

Conclusions: The authors provided evidence of significant associations between certain fatty acids and periodontitis and its severity, highlighting their contributory role, although the evidence does not support a causal role based on the results of MR-based analyses.

Practical Implications: The results of this study support a contributory or inhibitory role of fatty acids in the progression of periodontitis, although not as a direct cause, and underscored the importance of maintaining a balanced dietary lipid profile for periodontal health.