Are imprecise methods obscuring a relation between fat and breast cancer?
Pooled analyses of cohort studies show no relation between fat intake and breast-cancer risk. However, food-frequency questionnaire (FFQ) methods used in these studies are prone to measurement error. We assessed diet with an FFQ and a detailed 7-day food diary in 13070 women between 1993 and 1997. We compared 168 breast-cancer cases incident by 2000 with four matched controls. Risk of breast cancer was associated with saturated-fat intake measured with the food diary (hazard ratio 1.22 [95% CI 1.06-1.40], p=0.005, per quintile increase in energy-adjusted fat intake), but not with saturated fat measured with the FFQ (1.10 [0.94-1.29], p=0.23). Dietary measurement error might explain the absence of a significant association between dietary fat and breast-cancer risk in cohort studies.
Bingham
Sheila A
SA
MRC Dunn Human Nutrition Unit, Welcome Trust/MRC Building, Hills Road, CB2 2XY, Cambridge, UK. sab@mrc-dunn.cam.ac.uk <sab@mrc-dunn.cam.ac.uk>
Luben
Robert
R
Welch
Ailsa
A
Wareham
Nicholas
N
Khaw
Kay-Tee
KT
Day
Nicholas
N
D000368:Aged; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000209:etiology; D015331:Cohort Studies; D015930:Diet Records; D004041:Dietary Fats / Q000008:administration & dosage / Q000009:adverse effects*; D004435:Eating; D005260:Female; D006304:Health Status; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012107:Research Design / Q000592:standards*; D012307:Risk Factors; D011795:Surveys and Questionnaires
D004041:Dietary Fats