title: Effect of chewing betel nut (Areca catechu) on salivary cortisol measurement.
abstract: OBJECTIVE
  Cultural practices may compromise the accuracy of salivary hormone measurements and must be considered when designing human biology research protocols. This study aims to evaluate the acute effect of one common human practice-chewing betel nut-on the measurement of salivary cortisol levels under field conditions.
  
  
  METHODS
  Data were collected from 17 adult habitual betel nut users (males = 11; females = 6; mean age = 32.8 years) from a small rural community in Papua New Guinea. Saliva was collected in time series from each participant before and at 0, 15, 30, 45, 60, and 75 min after chewing betel nut. Samples were analyzed by radioimmunoassay and cortisol levels were compared across time using linear mixed effects modeling.
  
  
  RESULTS
  Measured mean cortisol concentration fell nearly 40% immediately following betel nut use and remained significantly below baseline levels for the following 45 min (all P < 0.05). Cortisol concentrations measured at 60 min and 75 min were indistinguishable from baseline levels (all P > 0.16).
  
  
  CONCLUSIONS
  Chewing betel nut is associated with a transient but significant reduction in measured levels of salivary cortisol. Future research must take this into account in populations where betel nut use is prevalent.
authors.affiliation: Department of Zoology, Faculty of Science, University of South Bohemia, České Budějovice, 37005, Czech Republic.|New Guinea Binatang Research Center, Madang, Papua New Guinea.
authors.forename: Martina
authors.initials: M
authors.lastname: Konečná
authors.affiliation: New Guinea Binatang Research Center, Madang, Papua New Guinea.|Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, 02138.
authors.forename: Samuel S
authors.initials: SS
authors.lastname: Urlacher
mesh_terms: D000293:Adolescent; D000328:Adult; D001114:Areca; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis*; D008297:Male; D008409:Mastication; D008875:Middle Aged; D010219:Papua New Guinea; D011863:Radioimmunoassay; D012463:Saliva / Q000737:chemistry*; D055815:Young Adult
chemical_list: D006854:Hydrocortisone
keywords: radioimmunoassay; saliva; stress hormones