6 Surprising Facts About Your Breasts

Your breasts are pretty remarkable—you may not know everything they can do.

1 / 7

Whether you love them or hate them, your boobs are responsible for incredible things. But we bet you don’t know everything they can do. First, let’s start with the obvious.

It’s remarkable that our breasts have the ability to make milk and feed our babies, says Kristi Weaver, DO, OB-GYN at Overland Park Regional Medical Center in Kansas. “I see it every day, and I still almost don't believe it,” says Dr. Weaver. In addition to providing nourishment for your newborn, here are 6 more amazing facts about your ta-ta’s.

Medically reviewed in November 2019.

They’re not identical.

2 / 7 They’re not identical.

If your bra seems tighter on one side of your chest, you’re not imagining things—most women have one breast that’s up to 20 percent of a cup size larger, says Weaver. Another fun fact: more than 60 percent of women have a left breast that is larger than the right.

Experts don’t know exactly what causes the variation in size, but hormonal changes like puberty, pregnancy or menopause are likely contributors. A traumatic injury to the chest and non-cancerous tumors called fibroadenomas, can also lead to the size fluctuation. Don’t fret if you have asymmetrical breasts though—it’s totally normal.

Nipples can trigger an orgasm.

3 / 7 Nipples can trigger an orgasm.

A little nipple stimulation may send you on the fast track to orgasm. “Interestingly, nipple stimulation activates the same region of the brain that is activated by clitoral and vaginal touch,” says Weaver. This area of the brain is known as the genital sensory cortex, and it’s activated by the stimulation of the clitoris, cervix and vagina, too.

And while only a small percentage of women are able to orgasm with nipple stimulation alone, it can certainly enhance a genital orgasm, Weaver adds. Nipple stimulation can include kissing, touching and sucking, but what feels good is different for everyone. If you’re curious, talk to your partner about experimenting while in the sack.

Your breasts are constantly changing.

4 / 7 Your breasts are constantly changing.

It’s normal for your breast size and density to fluctuate as you age. “When we're young, we have more glandular tissue in our breasts and as we age, it changes to more fatty tissue,” says Weaver.

Pregnancy, breast feeding and weight fluctuations cause density changes and sagging, too. “When you have too much weight loss or gain, the glandular tissue in your breast is replaced with fatty tissue. It’s difficult to regain glandular tissue,” says Weaver. Sun exposure and smoking causes damage to the outer tissue of the breasts.

Want to keep your breasts perky? Quit smoking, stay out of the sun, maintain a healthy weight, and eat more collagen-building foods, recommends Weaver.

The color and size of your nipple can grow or change.

5 / 7 The color and size of your nipple can grow or change.

There’s no “normal” when it comes to nipple and areola color and size. “Some women have very small nipples and small areolar tissue, while some women have very large areolas,” says Weaver.

Why? It probably has a lot to do with your hormones—particularly during pregnancy. You may notice an increase in your nipple and areola size and color after puberty, and especially during pregnancy.

“Huge amounts of estrogen and progesterone during pregnancy increase the size of that tissue and causes some darkening of the area,” says Weaver. The color change is really thought to help infants better identify the nipple from the surrounding breast tissue so they can feed better, adds Weaver.

A bad bra can cause sagging.

6 / 7 A bad bra can cause sagging.

If your breasts aren’t getting enough support, they’re going to start drooping. “It's estimated that over 80 percent of women aren't wearing the correct size bra, and improper support can lead to sagging,” says Weaver. Properly fitted bras should lift you up and help breasts keep their shape.

Exercise bras are important, too. High impact workouts can cause your breasts to move as much as eight inches up and down depending on your breast size, says Weaver. “Eight inches of movement during a 30-minute workout can cause lot of stress on the breast tissue over time.”

The best thing you can do is get a proper bra fitting. Once your girls are in the right bra, you'll feel more confident, too.

Breastfeeding is good for mom, too.

7 / 7 Breastfeeding is good for mom, too.

Just like babies, moms who breastfeed reap the benefits. Breastfeeding helps decrease the size of the uterus. “Lactation, or milk letdown, is actually stimulated by the same hormone in the brain, oxytocin, that causes uterine contraction,” explains Weaver. “When we breast feed our babies, the oxytocin hormone is released and the uterus contracts down.”

Weaver says breastfeeding triggers the brain to release the “feel good” hormone prolactin and helps moms feel more at ease. Women who breastfeed can also burn up to 500 extra calories per day, says Weaver.

That's not all: one large study involving nearly 290,000 Chinese women found that mothers who nursed their babies lowered their own risk of having a heart attack or stroke by about 10 percent compared to moms who never breastfed. The findings, published in the Journal of the American Heart Association, also discovered that the longer women breastfed, the lower their risk of heart disease.

Breastfeeding can also help lower your risk of postpartum hemorrhage, and breast and ovarian cancer long-term.

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