Eating more vegetables was found to help women reduce the risk of estrogen receptor-negative breast cancer, according to a study published in the Journal of the National Cancer Institute last week.
Estrogen receptor-negative breast cancer tumours do not respond to circulating estrogen, they make up between 15% and 20% of breast cancer cases and the survival rate is lower than for other types of breast cancer.
According to previous research, a higher intake of fruit and vegetables has been associated with a lower risk of breast cancer. However, because of the low incidence of estrogen receptor-negative breast cancers, large pooled analyses were needed for precise evaluation of the link between fruit and vegetable consumption and these types of breast cancer, the researchers noted.
A team led by Seungyoun Jung of Network Medicine, Brigham and Women's Hospital analysed 20 previous studies that covered over 993,000 women followed for 11 to 20 years, including nearly 5,000 cases of estrogen receptor-negative breast cancer. A significant association was found between a higher fruit and vegetable intake and a reduced risk of estrogen receptor-negative breast cancer, but there was no such link with breast cancers that respond to estrogen, called estrogen receptor-positive breast cancers, or with breast cancer overall.
In addition, the researchers found that there was a stronger link between the reduced risk for estrogen receptor-negative breast cancer and a higher consumption of vegetables. The association with total fruit intake was not statistically significant, the analysis showed.