The list of health benefits associated with breastfeeding is a long one -- preventing postpartum depression, reducing stress and promoting weight loss are just a few. Now, mothers can potentially add breast cancer resistance to that lengthy list.
A new study, published in the Journal of the National Cancer Institute, found that breastfeeding was associated with a better prognosis and higher survival rates among breast cancer patients with certain types of tumors.
To find this out, researchers looked at survey data and tumor tissue samples from 1,636 women previously diagnosed with breast cancer. If a patient had a history of breastfeeding, she had a 30 percent decreased risk of breast cancer recurrence; that percentage only increased if the patient breastfed for six months or more. Breastfeeding was also associated with a 28 percent decreased risk of breast cancer-related death.
A possible explanation, according to the researchers, is that breastfeeding speeds up the maturation of progenitor cells in the breasts, which normally expand during pregnancy, and might eventually lead to a less aggressive type of breast cancer that is treatable with hormonal therapy and generally has better prognosis.
It's important to note that the findings were only statistically significant when it came to luminal A tumors, the most common type among breast cancer patients. The researchers also found an improved prognosis for those with luminal B and basal-like tumors, but those findings weren't statistically significant.
If this doesn't sound new, that's because there's been promising evidence of breastfeeding's ability to guard against breast cancer in the past. But this study seems to be the first piece of compelling evidence that breastfeeding can decrease breast cancer recurrence for a particular tumor subtype.