Estimation of caffeine intake in Japanese adults using 16 d weighed diet records based on a food composition database newly developed for Japanese populations.
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.
Yamada
Mai
M
Department of International Health, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Sasaki
Satoshi
S
Murakami
Kentaro
K
Takahashi
Yoshiko
Y
Okubo
Hitomi
H
Hirota
Naoko
N
Notsu
Akiko
A
Todoriki
Hidemi
H
Miura
Ayako
A
Fukui
Mitsuru
M
Date
Chigusa
C
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*
D003069:Coffee; D013662:Tea; D002110:Caffeine