Serum zinc and periodontitis in non‐diabetic smoking and non‐smoking adults: NHANES 2011–2014

Abstract Objective This study aimed to evaluate the association of serum zinc with periodontitis in non‐diabetics based on smoking status, using a representative sample of adults in the United States. Methods A total of 1051 participants who underwent full‐mouth periodontal examination and serum zinc testing were enrolled from NHANES 2011 to 2014. The covariate‐adjusted association of serum zinc concentrations with periodontitis was explored using multivariable logistic regression, restricted cubic spines, and sensitivity analysis. Results The mean age of the 1051 adults was 54.5 years, 59.37% were male, and 20.65% had periodontitis. Analysis of the results showed that serum zinc was associated with periodontitis. The overall adjusted odds of periodontitis were 9% (odds ratio [OR]: 0.91; 95% confidence interval [CI]: 0.83–1.00) and 14% (OR: 0.86; 95% CI: 0.75–0.98) for nonsmokers and smokers, respectively. Smokers with T3 serum zinc exhibited a 53% reduction in the fully adjusted odds of periodontitis (OR: 0.47; 95% CI: 0.23–0.96), when compared to the reference group (T1 serum zinc), with serum zinc as the categorical variable. Conclusions Serum zinc levels were associated with the risk of periodontitis in non‐diabetic smokers but not non‐smokers.