Association of intakes of fat, dietary fibre, soya isoflavones and alcohol with uterine fibroids in Japanese women.

Certain dietary components which could affect oestrogen may have implications in the aetiology of uterine fibroids. We previously found that soya intake was inversely associated with a subsequent risk of hysterectomy, suggesting a potentially protective effect of soya against uterine fibroids, the major clinical indication for hysterectomy. We cross-sectionally assessed the associations of intakes of fat, soya foods, dietary fibre and alcohol with uterine fibroids. Study subjects were 285 premenopausal Japanese women participating in a health-check up programme, including gynaecological examinations, provided by a general hospital between October 2003 and March 2006. The presence of fibroids was confirmed by transvaginal sonogram. If women had undergone hysterectomy, self-report of fibroids was accepted. Each subject's usual diet, including alcohol, was determined with the use of a validated FFQ. Fifty-four women were identified as prevalent cases of fibroids or having had hysterectomy due to fibroids. The mean alcohol intake was statistically significantly higher among women with fibroids than among those without fibroids after controlling for known or suspected risk factors. For the highest compared with the lowest tertile of alcohol intake, the OR of uterine fibroids was 2.78 (95% CI 1.25, 6.20). There was no significant association of intake of fats, soya isoflavones or dietary fibre with uterine fibroids. The data suggest that higher alcohol intake is associated with a higher prevalence of uterine fibroids. Further studies on diet, especially phyto-oestrogens, and uterine fibroids are needed given the limited data currently available.