Alcohol and dietary fibre intakes affect circulating sex hormones among premenopausal women.
BACKGROUND
The association of alcohol and fibre intake with breast cancer may be mediated by circulating sex hormone levels, which are predictors of breast cancer risk.


OBJECTIVE
To evaluate the relationship of alcohol and dietary fibre intake with circulating sex hormone levels among premenopausal women.


METHODS
A total of 205 premenopausal women completed a validated food-frequency questionnaire at baseline and after 2 years; blood samples taken at the same time were analysed for circulating sex hormone concentrations, including oestrone (E1), oestradiol (E2), free E2, progesterone, androstenedione and sex hormone-binding globulin, by radioimmunoassay. We used mixed models to estimate least-square means of sex hormone concentrations for alcohol intake categories and quartiles of dietary intake.


RESULTS
After adjustment for covariates, alcohol consumption was moderately associated with higher circulating oestrogen levels; those who consumed more than one drink per day had 20% higher E2 (Ptrend=0.07) levels than non-drinkers. In contrast, higher dietary fibre intake was associated with lower serum levels of androstenedione (-8% between the lowest and highest quartiles of intake, Ptrend=0.06), but not oestrogens. Similarly, consumption of fruits (-12%, Ptrend=0.03), vegetables (-9%, Ptrend=0.15) and whole grains (-7%, Ptrend=0.07) showed inverse associations with androstenedione levels.


CONCLUSIONS
The consistency of the observed differences in sex hormone levels associated with alcohol and fibre-rich foods indicates that these nutritional factors may affect sex hormone concentrations and play a role in breast cancer aetiology and prevention.
Maskarinec
Gertraud
G
Cancer Research Center of Hawaii, 1236 Lauhala Street, Honolulu, HI 96813, USA. gertraud@crch.hawaii.edu
Morimoto
Yukiko
Y
Takata
Yumie
Y
Murphy
Suzanne P
SP
Stanczyk
Frank Z
FZ
D000293:Adolescent; D000328:Adult; D000428:Alcohol Drinking / Q000097:blood*; D000728:Androgens / Q000097:blood; D000735:Androstenedione / Q000097:blood; D001943:Breast Neoplasms / Q000097:blood* / Q000209:etiology / Q000517:prevention & control; D004034:Diet Surveys; D004043:Dietary Fiber / Q000008:administration & dosage*; D002523:Edible Grain; D004958:Estradiol / Q000097:blood; D004967:Estrogens / Q000097:blood*; D005260:Female; D005638:Fruit; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006801:Humans; D017697:Premenopause / Q000097:blood; D011374:Progesterone / Q000097:blood; D012307:Risk Factors; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D011795:Surveys and Questionnaires; D014675:Vegetables
D000728:Androgens; D004043:Dietary Fiber; D004967:Estrogens; D012739:Gonadal Steroid Hormones; D012738:Sex Hormone-Binding Globulin; D000735:Androstenedione; D011374:Progesterone; D004958:Estradiol