To mark National Breast Cancer Month in October, AICR is highlighting one of the least recognized findings from its latest report: mothers who breastfeed have lower risk of breast cancer. The lower risk is modest, but it is one additional motive to breastfeed for moms who are able.
Research also suggests that babies who are breastfed are less likely to gain excess weight as they grow. Among adults, AICR research shows that overweight and obesity increases the risk of 11 common cancers.
“It isn’t always possible for moms to breastfeed but for those who can, know that breastfeeding can offer cancer protection for both the mother and the child,” said AICR’s Director of Nutrition Programs Alice Bender, MS, RDN.”
AICR recommends that new mothers breastfeed exclusively for up to six months and then add other liquids and foods. This advice is in line with recommendations of other health organizations, including the World Health Organization. Breastfeeding provides the nutrients babies need, helps protect them from infections and asthma and boosts their immune system.
AICR’s report updating the global scientific evidence on breast cancer identified and reviewed the 18 studies on lactation. Thirteen of these studies focused on length of time, showing a 2 percent decreased risk per 5-month increase in breastfeeding duration. The report Diet, Nutrition, Physical Activity and Breast Cancer is part of the Continuous Update Project (CUP) from AICR and the World Cancer Research Fund (WCRF).
There are several possible ways by which breastfeeding may influence breast cancer risk. Lactation may delay a new mother’s menstrual periods, reducing lifetime exposure to hormones like estrogen, which is linked to breast cancer risk. The shedding of breast tissue after lactation may also help rid cells with DNA damage.
Diet, Nutrition, Physical Activity and Breast Cancer found many other lifestyle links to breast cancer risk. Avoiding alcohol, being physically active and staying a healthy weight were also found to lower risk of this cancer. Previous reports from AICR and WCRF have found that – in addition to post-menopausal breast cancer – excess body fat increases risk for ovarian, esophageal, colorectal, gallbladder, liver, endometrial, kidney, stomach cardia, pancreatic, and advanced prostate cancers.
“With the many benefits of breastfeeding it’s important that new moms get support to successfully breastfeed for longer than a few days or weeks,” says Bender. “It’s also critical to know there are steps all women can take to lower the risk of this cancer.”
Sources: AICR and World Cancer Research Fund. Diet, Nutrition, Physical Activity, and Breast Cancer. May 2017.