title: Saliva pH affects the sweetness sense.
abstract: OBJECTIVE
  The aim of this study was to establish a prediction system for taste sense according to the biochemical data of saliva.
  
  
  METHODS
  The present study included 100 participants ages ≥20 y without physical, mental, or dental disabilities. Saliva samples were collected from the participants and subjected to biochemical analyses. Taste examination (sweetness, saltiness, sourness, and bitterness) was performed using the dropped disk method. Correlation analysis and multiple regression analysis were performed between the taste sense properties and biochemical data of saliva.
  
  
  RESULTS
  Multiple regression analysis demonstrated that sweetness sensitivity (in which a higher score indicates lower sensitivity) was significantly affected by various biochemical properties, with the strongest influence being pH. The following prediction equation was determined: Sweetness sensitivity = 1.38 + (-0.12 × low pH [1: If pH <6.7, 0: otherwise]) + (0.80 × high pH [1: If pH >7.3, 0: otherwise]) + (0.04 × Fe [μg/dL]). Analysis of variance showed an overall significant effect of these variables on sweetness sensitivity (R2= 0.74; P < 0.01).
  
  
  CONCLUSIONS
  Saliva pH most strongly affects the sweetness sensitivity. This prediction can be used for evaluations of variations in dietary choices and to help individuals make healthy food choices to maintain health.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Tokai University School of Medicine, Kanagawa, Japan; Department of Oral and Maxillofacial Surgery, Tokai University Oiso Hospital, Kanagawa, Japan. Electronic address: k-aoyama@tokai-u.jp.
authors.forename: Ken-Ichi
authors.initials: KI
authors.lastname: Aoyama
authors.affiliation: Department of Health and Welfare, Okayama Prefectural Government, Uchi-Yamashita Okayama, Japan.
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Okino
authors.affiliation: Department of Oral and Maxillofacial Surgery, Tokai University School of Medicine, Kanagawa, Japan; Department of Oral and Maxillofacial Surgery, Tokai University Oiso Hospital, Kanagawa, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamazaki
authors.affiliation: Department of Oral and Maxillofacial Surgery, Tokai University School of Medicine, Kanagawa, Japan; Department of Oral and Maxillofacial Surgery, Tokai University Oiso Hospital, Kanagawa, Japan.
authors.forename: Rena
authors.initials: R
authors.lastname: Kojima
authors.affiliation: Department of Oral and Maxillofacial Surgery, Tokai University School of Medicine, Kanagawa, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Uchibori
authors.affiliation: Department of Oral and Maxillofacial Surgery, Tokai University School of Medicine, Kanagawa, Japan.
authors.forename: Yaushiro
authors.initials: Y
authors.lastname: Nakanishi
authors.affiliation: Department of Oral and Maxillofacial Surgery, Tokai University School of Medicine, Kanagawa, Japan.
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Ota
mesh_terms: D000328:Adult; D004032:Diet; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D012463:Saliva / Q000737:chemistry*; D013649:Taste; D055815:Young Adult
keywords: Biochemical data; Prediction equation of taste sensory; Saliva pH; Sweetness sense; Taste sensory prediction