Women’s breasts eat themselves after weaning

I have two children and one on the way, so I am no stranger to the pains of pregnancy or the truly weird stuff that happens to a woman’s body. As I type this, I am on a ridiculously strict diet, my hair is beginning to fall out, and when I walk I resemble a Weeble-Wobble and not a human being. Fun times.

So, imagine my dismay – and OK, if I’m being honest, my downright curiosity – when I read that after a woman finishes breastfeeding, her boobs LITERALLY EAT THEMSELVES. Sorry. That seemed worth yelling about.

In a fascinating article in New Scientist that has been making the rounds in parenting circles, researchers are looking at the bizarre way in which female breasts rid themselves of milk and milk producing cells when nursing is over. As it turns out, the human body uses a process called phagocytosis, which is when the body’s immune cells clean up problems like dead or dying cells throughout the body. But it doesn’t seem to be happening in boobs post-breastfeeding.

Matthew Naylor, a cancer biologist at the University of Sydney in Australia told New Scientist, “One of the least understood aspects of this process is how the excess milk and large numbers of dead cells are removed from the mammary gland without substantial activation of the immune system.”

It turns out that the immune system isn’t even consulted, instead epithelial cells, which are present in breast tissue, “eat their dead neighbors.” What are epithelial cells? According to the article in New Scientist:

“Women’s breasts comprise a network of ducts, covered by a layer of fatty tissue. During pregnancy, hormonal signals cause epithelial cells lining the ducts to proliferate and form ball-like structures called alveoli, which is where milk is made when the baby is born. However, once women stop breastfeeding, these structures self-destruct – a process that involves massive cellular suicide, and the removal of the debris.”

Researchers are excited about this discovery because they think it may shed some light on what happens during breast cancer. Even though it is widely known and touted by breastfeeding experts and the medical community that breastfeeding can significantly reduce the risk of breast cancer, “women have an increased risk of developing breast cancer for the first 5 to 10 years following pregnancy, and these cancers tend to be more aggressive.

So, there you have it, folks. When a mother is finished breastfeeding, her boobs will literally digest themselves.

Ain’t nature sweet?