Dietary antioxidants and periodontal disease in community-based older Japanese: a 2-year follow-up study

Objective: To investigate the longitudinal relationship between the intake of dietary antioxidants and periodontal disease in community-dwelling older Japanese. Design: A retrospective cohort study, with a follow-up of 2 years (2003-2005). Intakes of dietary antioxidants (vitamin C, vitamin E, alpha-carotene and beta-carotene) were assessed with a validated FFQ. Participants were classified by tertile of antioxidant intake. Full-mouth periodontal status, measured as the clinical attachment level, was recorded at baseline and follow-up examinations. Periodontal disease progression was considered as loss of attachment of 3mm or greater over the study period at the interproximal site for each tooth. Finally, the number of teeth with periodontal disease progression per person was calculated and was used as the outcome. Poisson regression analysis was conducted, with dietary antioxidants as the main exposure, to estimate their influence on the number of teeth with periodontal disease progression. Setting: Niigata City (Japan). Subjects: Dentate individuals aged 75 years in 2003, for whom data were available, were included in the analyses (n 264). Results: A higher intake of dietary antioxidants was inversely associated with the number of teeth with periodontal disease progression, controlling for other variables. The multivariate-adjusted incidence rate ratios in the first, second and third tertiles were 1.00, 0.76 (95% CI 0.60, 0.97) and 0.72 (95% CI 0.56, 0.93) for vitamin C; 1.00, 0.79 (95% CI 0.62, 0.99) and 0.55 (95% CI 0.42, 0.72), for vitamin E; and 1.00, 1.02 (95% CI 0.81, 1.29) and 0.73 (95% CI 0.56, 0.95) for beta-carotene. Conclusions: The study results suggest that higher intake of antioxidants may mitigate periodontal disease in community-dwelling older Japanese.