Dietary fibre and risk of breast cancer in the UK Womens Cohort Study.

In this large prospective study, baseline data was collected for 35,792 women aged 35-69 years residing in the UK (England, Wales, Scotland) between 1995 and 1998.  A self-administered food frequency questionnaire was used to examine amounts of dietary fibre in grams per day.  Dietary fibre fractions were estimated by evaluating fibre consumption derived from relevant food groups.  The relationship between dietary fibre intake and breast cancer was established via Cox?s proportional hazards regression using Stata version 9.1.  The effect of fibre was also examined separately for pre-and-post menopausal breast cancer. 

Results demonstrated that after 7.5 years of follow-up, 350 post-menopausal and 257 pre-menopausal developed invasive breast cancer.  Intakes of total fibre varied from <20g/day in the lowest quintile to >30g/day in the highest quintile.  An inverse relationship between total fibre intake and risk of breast cancer was observed in pre-menopausal women.  Intake of fibre from cereals was also inversely associated with risk of breast cancer in pre-menopausal women, while a non-significant inverse association was observed for fibre intake from fruit in the same group of women.  No significant relationship between total fibre, fibre from cereal or fruit, and risk of breast cancer was observed in post-menopausal women.  

These findings suggest that total fibre intake is protective against breast cancer in pre-menopausal women.  Of particular importance is that fibre from cereals and potentially fruit may be responsible for the observed inverse relationship between fibre intake and breast cancer risk in pre-menopausal women.