title: Estimation of caffeine intake in Japanese adults using 16 d weighed diet records based on a food composition database newly developed for Japanese populations.
abstract: OBJECTIVE
  Previous studies in Western populations have linked caffeine intake with health status. While detailed dietary assessment studies in these populations have shown that the main contributors to caffeine intake are coffee and tea, the wide consumption of Japanese and Chinese teas in Japan suggests that sources of intake in Japan may differ from those in Western populations. Among these teas, moreover, caffeine content varies widely among the different forms consumed (brewed, canned or bottled), suggesting the need for detailed dietary assessment in estimating intake in Japanese populations. Here, because a caffeine composition database or data obtained from detailed dietary assessment have not been available, we developed a database for caffeine content in Japanese foods and beverages, and then used it to estimate intake in a Japanese population.
  
  
  METHODS
  The caffeine food composition database was developed using analytic values from the literature, 16 d weighed diet records were collected, and caffeine intake was estimated from the 16 d weighed diet records.
  
  
  METHODS
  Four areas in Japan, Osaka (Osaka City), Okinawa (Ginowan City), Nagano (Matsumoto City) and Tottori (Kurayoshi City), between November 2002 and September 2003.
  
  
  METHODS
  Two hundred and thirty Japanese adults aged 30-69 years.
  
  
  RESULTS
  Mean caffeine intake was 256.2 mg/d for women and 268.3 mg/d for men. The major contributors to intake were Japanese and Chinese teas and coffee (47 % each). Caffeine intake above 400 mg/d, suggested in reviews to possibly have negative health effects, was seen in 11 % of women and 15 % of men.
  
  
  CONCLUSIONS
  In this Japanese population, caffeine intake was comparable to the estimated values reported in Western populations.
authors.affiliation: Department of International Health, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Mai
authors.initials: M
authors.lastname: Yamada
authors.forename: Satoshi
authors.initials: S
authors.lastname: Sasaki
authors.forename: Kentaro
authors.initials: K
authors.lastname: Murakami
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Hitomi
authors.initials: H
authors.lastname: Okubo
authors.forename: Naoko
authors.initials: N
authors.lastname: Hirota
authors.forename: Akiko
authors.initials: A
authors.lastname: Notsu
authors.forename: Hidemi
authors.initials: H
authors.lastname: Todoriki
authors.forename: Ayako
authors.initials: A
authors.lastname: Miura
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Fukui
authors.forename: Chigusa
authors.initials: C
authors.lastname: Date
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D001628:Beverages / Q000032:analysis; D002110:Caffeine / Q000008:administration & dosage* / Q000009:adverse effects / Q000032:analysis*; D003069:Coffee / Q000737:chemistry*; D016208:Databases, Factual; D004032:Diet / Q000706:statistics & numerical data*; D015930:Diet Records; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D015596:Nutrition Assessment; D017678:Sex Distribution; D013662:Tea / Q000737:chemistry*
chemical_list: D003069:Coffee; D013662:Tea; D002110:Caffeine