Tea consumption and incidence of type 2 diabetes in Europe: the EPIC-InterAct case-cohort study.
BACKGROUND
In previous meta-analyses, tea consumption has been associated with lower incidence of type 2 diabetes. It is unclear, however, if tea is associated inversely over the entire range of intake. Therefore, we investigated the association between tea consumption and incidence of type 2 diabetes in a European population.


RESULTS
The EPIC-InterAct case-cohort study was conducted in 26 centers in 8 European countries and consists of a total of 12,403 incident type 2 diabetes cases and a stratified subcohort of 16,835 individuals from a total cohort of 340,234 participants with 3.99 million person-years of follow-up. Country-specific Hazard Ratios (HR) for incidence of type 2 diabetes were obtained after adjustment for lifestyle and dietary factors using a Cox regression adapted for a case-cohort design. Subsequently, country-specific HR were combined using a random effects meta-analysis. Tea consumption was studied as categorical variable (0, >0-<1, 1-<4, ≥ 4 cups/day). The dose-response of the association was further explored by restricted cubic spline regression. Country specific medians of tea consumption ranged from 0 cups/day in Spain to 4 cups/day in United Kingdom. Tea consumption was associated inversely with incidence of type 2 diabetes; the HR was 0.84 [95%CI 0.71, 1.00] when participants who drank ≥ 4 cups of tea per day were compared with non-drinkers (p(linear trend) = 0.04). Incidence of type 2 diabetes already tended to be lower with tea consumption of 1-<4 cups/day (HR = 0.93 [95%CI 0.81, 1.05]). Spline regression did not suggest a non-linear association (p(non-linearity) = 0.20).


CONCLUSIONS
A linear inverse association was observed between tea consumption and incidence of type 2 diabetes. People who drink at least 4 cups of tea per day may have a 16% lower risk of developing type 2 diabetes than non-tea drinkers.
Geertruida J
GJ
van Woudenbergh
Anneleen
A
Kuijsten
Dagmar
D
Drogan
Daphne L
DL
van der A
Dora
D
Romaguera
Eva
E
Ardanaz
Pilar
P
Amiano
Aurelio
A
Barricarte
Joline W J
JW
Beulens
Heiner
H
Boeing
H Bas
HB
Bueno-de-Mesquita
Christina C
CC
Dahm
M-Doleres
MD
Chirlaque
Francoise
F
Clavel
Francesca L
FL
Crowe
Piia-Piret
PP
Eomois
Guy
G
Fagherazzi
Paul W
PW
Franks
Jytte
J
Halkjaer
Kay T
KT
Khaw
Giovanna
G
Masala
Amalia
A
Mattiello
Peter
P
Nilsson
Kim
K
Overvad
J
J
Ramón Quirós
Olov
O
Rolandsson
Isabelle
I
Romieu
Carlotta
C
Sacerdote
María-José
MJ
Sánchez
Matthias B
MB
Schulze
Nadia
N
Slimani
Ivonne
I
Sluijs
Annemieke M W
AM
Spijkerman
Giovanna
G
Tagliabue
Anne
A
Tjønneland
Rosario
R
Tumino
Nita G
NG
Forouhi
Stephen
S
Sharp
Claudia
C
Langenberg
Edith J M
EJ
Feskens
Elio
E
Riboli
Nicholas J
NJ
Wareham
D000328:Adult; D000368:Aged; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology* / Q000517:prevention & control; D004327:Drinking Behavior; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017711:Nonlinear Dynamics; D012306:Risk; D011795:Surveys and Questionnaires; D013662:Tea; D055815:Young Adult
D013662:Tea