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Breast cancer risk reduced through breastfeeding

If you could significantly reduce your breast cancer risk, would you do everything in your power to do so? In 2012, it was estimated there were more than 226,000 new cases of invasive breast cancer in women in the United States. But we don’t need statistics to make us aware of this disease.

What you might not know: Breastfeeding may decrease a woman’s breast cancer risk. In fact, for women with a family history of the disease, it may cut their risk drastically.

The research

There’s been a lot of support for the protective role of breastfeeding throughout the years. Recent research shows women who carry the BRCA1 gene may be able to reduce their risk of breast cancer— by 32 percent—simply by breastfeeding for at least one year.

The study shows the breastfeeding does not have to be exclusive without formula use or supplementing with other foods. In other words, out of five women with this gene who breastfeed longer than one year can reduce their risk of developing cancer. In another study, for women with a family history, breastfeeding cut their risk for invasive breast cancer by nearly 60 percent. 

This reduction in risk was comparable to high-risk women taking the anti-estrogen drug Tamoxifen. Of course, unlike Tamoxifen, breastfeeding is good for mothers and babies. But the protective benefits don’t stop there.

Women without any family history may be able to decrease their risk of breast cancer, too. The more months or years a mom breastfeeds, the lower her risk.

How is breast cancer risk reduced?

We don’t know exactly how breastfeeding is protective, but there are a few theories. More research is needed, but it’s no doubt there’s a connection at play. Plus, it’s just one more reason why breastfeeding isn’t just healthy for babies, it’s healthy for moms, too.

  • It causes hormonal changes, such as a decrease in the level of estrogen. Lower levels of estrogen may decrease a woman’s risk.
  • It suppresses ovulation. Women who have fewer menstrual cycles during the course of their reproductive lives may have less risk.
  • It causes physical changes to breast cells that make them more resistant to cancer-related mutations.
  • It causes an increase in prolactin (a hormone responsible for milk production), which blocks a gene that makes breast cancer more aggressive.