title: Prevalence of cholesterol gallstones positively correlates with per capita daily calorie intake.
abstract: OBJECTIVE
  Gallstone composition has changed over the past decades in East Asian countries with a prominent increase in the prevalence of cholesterol gallstones. This trend is possibly due to the westernization of dietary habits. This study was undertaken to delineate the changing trends in gallstone composition in Japan since the 1920s and to assess dietary influences on gallstone composition.
  
  
  METHODS
  Between 1971 and 1999, 1264 Japanese patients underwent cholecystectomy for gallstone disease in Niigata University Medical Hospital. Gallbladder stones retrieved from each patient were classified into four types by gross inspection of the cut surface and infrared spectroscopy: cholesterol stone, black pigment stone, brown pigment stone, and other stones. The literature was reviewed to find both changing trends in gallstone composition before 1971 and dietary changes since 1950 in Japan.
  
  
  RESULTS
  The prevalence of cholesterol gallstones among Japanese patients undergoing cholecystectomy increased steadily until the 1970s and declined thereafter (P<0.001). Among dietary factors, only per capita daily total calorie intake strongly correlated with cholesterol gallstone prevalence (r=0.93, P=0.02).
  
  
  CONCLUSIONS
  During the 20th century, the prevalence of cholesterol gallstones in the Japanese population increased steadily until the 1970s declining thereafter. Per capita daily total calorie intake appears to be the predominant dietary factor affecting cholesterol gallstone prevalence.
authors.affiliation: Division of Digestive and General Surgery, Niigata University Graduate School of Medical and Dental Sciences, Niigata City, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Tsunoda
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Shirai
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Hatakeyama
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002784:Cholesterol / Q000097:blood*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D002149:Energy Intake; D005260:Female; D005706:Gallbladder Neoplasms / Q000097:blood / Q000453:epidemiology / Q000601:surgery; D042882:Gallstones / Q000097:blood / Q000145:classification / Q000453:epidemiology* / Q000601:surgery; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D013223:Statistics as Topic
chemical_list: D002784:Cholesterol