Researchers at the Washington University School of Medicine in St Louis said that previous studies looked at breast cancer risk and alcohol consumption in later life or the effects of adolescent drinking on non-cancerous breast disease.
Co-author Professor Graham Colditz said in the study published yesterday in the Journal of the National Cancer Institute that heavy drinking increasingly occurred on college campuses and during adolescence.
“According to our research…if a female averages a drink per day between her first period and her first full-time pregnancy, she increases her risk of breast cancer by 13%,” Colditz said.
“Reducing drinking to less than one drink per day, especially during this time period, is a key strategy to reducing lifetime risk of breast cancer,” he added.
Benign breast disease risk
The Liu et al. study also found that young women increased their risk of benign breast disease (BBD) by 15% for every bottle of beer, glass of wine or liquor shot drunk daily
Despite being non-cancerous, the team said these lesions increase breast cancer risk by as much as 500%, and urged parents to educate their daughter on the risk during a “critical” time period.
Liu et al. base their findings on a review of the health histories of 91,005 mothers (all nurses) enrolled in the Nurses’ Health Study from 1989 to 2009, identifying 1,609 breast cancer cases and 970 BBD cases.
The team didn’t consider the effects of adolescent and early adult drinking on women who didn’t have a full-term pregnancy, since not enough representative women took part in these studies.
Offset alcohol’s harmful effects
Breast cells are particularly susceptible to cancer-causing substances due to rapid growth during adolescence and later, Liu et al. said, while risks are heightened by the growing average time between a girl’s first menstrual cycle and first full-time pregnancy.
Calling for more research into how young women can counteract alcohol’s adverse effects, Colditz said past studies suggested that eating more fiber and exercising lowered everyone’s cancer risk.
Title: ‘Alcohol intake between menarche and first pregnancy: A prospective study of breast cancer risk’
Authors: Liu Y., Colditz G.A., Rosner B., Berkey C.S., Collins L.C., Schnitt S.J., Connolly J.L., Chen W.Y., Willett W.C., Tamimi R.M.
Source: Journal of the National Cancer Institute, Published online August 28 2013, doi: 10.1093/jnci/djt213