Can Breast Milk Go Bad Inside Your Boobs? Science Responds


Breasts are really incredible things. Think about it — they're basically bags of fat and mushy tissue that occasionally fill up with what amounts to the world's most nutritious food as if by magic. Also, have you ever seen what your boobs can do when they're overfull? I could spray down a Cadillac and still have enough left over for snack time. But is it always perfect? What if you've not breastfed in a while? Can breast milk go bad inside your boobs? I'm not into feeding my baby spoiled milk. Year-old mustard? Sure, but not breast milk.

Your breasts are actually perfect regulators. If your body is producing milk, there is no way for it to spoil in the breast, according to the New Jersey Department of Health. This is because it is not a stagnant product of your body. It's not as though you make it, and then it sits in the breast until it is pumped or your baby eats. Instead, like blood, bile, and other bodily fluids, it is constantly regenerating inside the tissue. What's not used is reabsorbed into the blood system.

If it wasn't, weaning would be very problematic, as your breasts would just sit with leftover milk in them, likely leading to something unsavory.

The body is a regenerating machine. While there are some things that can't be regenerated — like those brain cells you lost watching nine hours of Real Housewives after your Kardashian binge — most things in your body keep remaking themselves or healing from damage. Think about what happens when you give blood. If you had a finite amount of blood, we'd all be screwed, but because blood is a renewable resource that your body manufactures from the foods you eat and the water you drink, it keeps replenishing. While it's much more complicated than that, dealing in bone marrow and whatnot, that's essentially what happens at the most basic level, according to the American Society of Hematology.

The same is true for breast milk. Your breasts, triggered by hormones, begin the process of making milk and continue that process as needed, judging by the demands you make upon it, like pumping and feeding, noted Sutter Health. If you discontinue feeding or pumping for any length of time, your supply will eventually dwindle and dry up accordingly. Although, it is possible to experience something called re-lactation, according to Breastfeeding Support. That's when you've delayed or dropped breastfeeding and pick it up much later. It requires a concerted effort for your body to begin to reproduce milk after it has stopped without a hormonal trigger, but it is possible and does happen.

Can milk go bad inside the breast, ever? No. That's the amazing thing. However, outside the breast is a different story altogether. According to the Centers for Disease Control and Prevention, breast milk can only be stored for six to eight hours at room temperature, in a cooler or cooler bag for 24 hours. Breast milk that's stored in the fridge, towards the back, at temperatures below 39 degrees Fahrenheit can be stored for a total of five days. In the freezer, it can be safely stored for three to six months. If you're lucky enough to have a deep freezer, it can be held safely for six to 12 months, right alongside your frozen lasagna and your son's goldfish, Charlie. Or the head of Walt Disney, whatever.

But worry not, my lactating friends. The milk in your own personal udders lasts indefinitely. As long as you're producing it, it's safe to drink. However, that yogurt in the back of your fridge that you're eyeing? Do you even remember when you bought that?

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