title: Increased physical activity decreases periodontitis risk in men.
abstract: BACKGROUND
  Increased physical activity improves insulin sensitivity and glucose metabolism, and may therefore affect incidence of periodontitis.
  
  
  METHODS
  We studied the association of physical activity, walking and periodontitis in 39,461 male, US based, health professionals, 40-75 years old at baseline, more than half of whom were dentists, being followed up continuously since 1986. Participants were free of periodontitis, coronary heart disease and stroke at the start of follow-up. Physical activity and periodontitis were measured by validated questionnaires (expressed in metabolic equivalents--METs); the first report of professionally diagnosed periodontitis was considered a case.
  
  
  RESULTS
  Periodontitis risk decreased by 3% for every 10-MET increase in average physical activity after adjustment for age, smoking, diabetes, BMI, alcohol consumption and total calories (RR = 0.97; 95% CI: 0.95-0.99). The inverse trend remained significant in the categorical analysis. Compared to men in the lowest quintile of physical activity, those in the highest quintile had a 13% lower risk of periodontitis (RR = 0.87; 95% CI: 0.76-1.01, p-value, test for trend = 0.02). In a sub-sample of men with radiographs (n = 137) the physically active had less average bone loss (beta = -0.29, p-value = 0.03) after multivariate adjustment compared to those inactive.
  
  
  CONCLUSIONS
  In this large-scale prospective study, we found an inverse, linear association between sustained physical activity and periodontitis independent of known risk factors. The benefits of a physically active lifestyle may extend to periodontal health.
authors.affiliation: Department of Nutrition, Harvard School of Public Health, Boston, MA 02115, USA. amerchan@hsph.harvard.edu
authors.forename: Anwar T
authors.initials: AT
authors.lastname: Merchant
authors.forename: Waranuch
authors.initials: W
authors.lastname: Pitiphat
authors.forename: Eric B
authors.initials: EB
authors.lastname: Rimm
authors.forename: Kaumudi
authors.initials: K
authors.lastname: Joshipura
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D002151:Calorimetry; D015331:Cohort Studies; D004734:Energy Metabolism / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005947:Glucose / Q000502:physiology; D006282:Health Personnel; D006801:Humans; D015994:Incidence; D007333:Insulin Resistance / Q000502:physiology; D008019:Life Style; D008297:Male; D008875:Middle Aged; D010518:Periodontitis / Q000453:epidemiology* / Q000378:metabolism / Q000517:prevention & control; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D014481:United States
chemical_list: D005947:Glucose