A prospective study of whole-grain intake and risk of type 2 diabetes mellitus in US women.
OBJECTIVE
This study examined the association between intake of whole vs refined grain and the risk of type 2 diabetes mellitus.


METHODS
We used a food frequency questionnaire for repeated dietary assessments to prospectively evaluate the relation between whole-grain intake and the risk of diabetes mellitus in a cohort of 75,521 women aged 38 to 63 years without a previous diagnosis of diabetes or cardiovascular disease in 1984.


RESULTS
During the 10-year follow-up, we confirmed 1879 incident cases of diabetes mellitus. When the highest and the lowest quintiles of intake were compared, the age and energy-adjusted relative risks were 0.62 (95% confidence interval [CI] = 0.53, 0.71, P trend < .0001) for whole grain, 1.31 (95% CI = 1.12, 1.53, P trend = .0003) for refined grain, and 1.57 (95% CI = 1.36, 1.82, P trend < .0001) for the ratio of refined- to whole-grain intake. These findings remained significant in multivariate analyses. The findings were most evident for women with a body mass index greater than 25 and were not entirely explained by dietary fiber, magnesium, and vitamin E.


CONCLUSIONS
These findings suggest that substituting whole- for refined-grain products may decrease the risk of diabetes mellitus.
Liu
S
S
Brigham and Women's Hospital, Harvard Medical School, Boston, USA. simin.liu@channing.harvard.edu
Manson
J E
JE
Stampfer
M J
MJ
Hu
F B
FB
Giovannucci
E
E
Colditz
G A
GA
Hennekens
C H
CH
Willett
W C
WC
D000328:Adult; D015992:Body Mass Index; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology* / Q000209:etiology* / Q000378:metabolism; D004032:Diet / Q000009:adverse effects; D004034:Diet Surveys; D002523:Edible Grain; D004734:Energy Metabolism; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D015999:Multivariate Analysis; D009726:Nurses; D011446:Prospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology