Eating more fibre can cut the risk of breast cancer in pre-menopausal women, according to scientists.
A study found that women with a high intake of fibre - particularly wholemeal bread and wholegrain cereal - cut their risk of breast cancer in half.
Researchers at the University of Leeds tracked the eating habits of more than 35,000 women for seven years. Their findings were published in the International Journal of Epidemiology.
Professor Janet Cade, who led the study, said: "Previous research hasn't shown a convincing link between increased dietary fibre and a lower risk of breast cancer. But earlier studies didn't draw any distinction between pre and post-menopausal women.
"Our study found no protective effect in the older group, but significant evidence of a link in the pre-menopausal women."
Out of the entire group, 350 pre-menopausal women developed breast cancer during the study. They were women who had a larger percentage of energy taken from protein than those who did not develop cancer.
They also had a lower intake of dietary fibre and vitamin C compared to those without cancer.
The authors suggested several possible reasons for the effect, including that high fibre foods are rich in vitamins, zinc and other nutrients which can act as anti-oxidants.
Another reason could be the link between breast cancer and the female hormone, oestrogen, with dietary fibre regulating oestrogen levels in the body.
This effect would be especially relevant to the pre-menopausal group, who naturally have higher levels of the hormone, the researchers said.
