FCCC LOGO Faculty Publications
Tseng M , Olufade T , Kurzer MS , Wahala K , Fang CY , van der Schouw YT , Daly MB
Food frequency questionnaires and overnight urines are valid indicators of daidzein and genistein intake in U.S. women relative to multiple 24-h urine samples
Nutr Cancer. 2008 ;60(5) :619-26
PMID: 18791925   
Back to previous list
Data regarding convenient, valid methods for measuring U.S. isoflavone intake are limited. We evaluated a soy food questionnaire (SFQ), the Willett food frequency questionnaire (FFQ), and overnight urine samples relative to excretion in 24-h urine samples. We also described intake among women in a high-risk program for breast or ovarian cancer. Between April 2002 and June 2003, 451 women aged 30 to 50 yr with a family history of breast or ovarian cancer completed the SFQ and FFQ. Of them, 27 provided four 24-h and overnight urine specimens. In these women, 24-h sample measures were correlated with SFQ estimates of daidzein (Spearman r = .48) and genistein (r = .54) intake, moderately correlated with the Willett FFQ (daidzein r = .38, genistein r = .33), and strongly correlated with overnight urine excretion (daidzein r = .84, genistein r = 0.93). Among all 451 SFQ respondents, mean (median) daidzein and genistein intakes were 2.8 (0.24) and 3.9 (0.30) mg/day. Primary sources of both were soymilk, soy nuts, and tofu. We conclude that targeted soy food questionnaires, comprehensive FFQs, and multiple overnight urines are all reasonable options for assessing isoflavone intake in epidemiologic studies.
Tseng, Marilyn Olufade, Temitope Kurzer, Mindy S Wahala, Kristiina Fang, Carolyn Y van der Schouw, Yvonne T Daly, Mary B CA-096414/CA/NCI NIH HHS/United States Evaluation Studies Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't United States Nutrition and cancer Nutr Cancer. 2008;60(5):619-26.