What Purpose Does the Belly Button Serve?

misuma/iStock via Getty Images
misuma/iStock via Getty Images

While your eyelashes are protecting your eyes, your lungs are letting you breathe, and virtually every other part of your body—inside and out—is performing its own relatively well-known task, your belly button is just sitting there collecting lint. And while it’s true that your navel served its most important purpose before you were born, it’s not totally useless now.

According to ZME Science, back when you were a fetus, your belly button was more of a belly portal: Your umbilical cord extended from it and connected you to the placenta on your mother’s uterine wall. That way, the placenta could channel nutrients and oxygen to you through the cord, and you could send back waste.

Your umbilical cord was cut when you were born, creating a tiny bulge that left behind some scar tissue after it healed. That scar tissue is your belly button, navel, or umbilicus. Though you may have heard that the shape of your belly button is a direct result of the scissor skills of the doctor who delivered you, that’s not true. Dr. Dan Polk, a neonatologist in the Chicago area, told the Chicago Tribune that a belly button's shape “has to do with how much baby skin leads onto the umbilical cord from the baby’s body. Less skin makes an innie; more skin makes an outie.” About 90 percent of people have innies.

Regardless of how your belly button looks, you probably don’t use it on a daily basis. However, if you’ve studied anatomy, medicine, or a related field, you might recognize it as the central point by which the abdomen is divided into the following quadrants: right upper, left upper, right lower, and left lower. Another way of classifying that area is into nine regions—including the hypochondriac, lumbar, iliac, epigastric, and hypogastric regions—with the umbilical region at the very center.

Blausen Medical, Wikimedia Commons // CC BY 3.0

Your belly button can also serve as the opening for laparoscopic surgery, which can save you from having a scar elsewhere on your abdomen.

The navel is a great central landmark outside of medicine, too. If you’ve taken yoga or Pilates classes, you may have heard it referred to as the center of balance or center of gravity. Because it sits right on top of your abdominal muscles, your belly button is an easy marker for your instructor to mention when they want you to access your core, which helps you balance.

And, of course, belly buttons are notorious for storing quite a bit of lint, which always seems to be blue (you can learn more about that here).

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8 of Amazon's Bestselling Home Office Desks

JOISCOPE/Amazon
JOISCOPE/Amazon

If you've been working from home for the past six months (or longer), you're overdue for a high-quality office desk. And not just any old one, but a desk designed specifically for comfort and purpose, so you can organize everything you need for your 9-to-5 without having to worry about losing track of that important folder or planner.

The problem, though, is that there are so many options out there to choose from. That’s why we've stepped in to make the process a bit easier for you by compiling a list of the bestselling home office desks from Amazon. Check them out below.

1. Furinno Simplistic A-Frame Computer Desk; $237

Furinno/Amazon

This Furinno A-Frame desk is Amazon’s top home office desk at the moment. Though it may seem simple, sometimes that's all you need to make your space more efficient. The small desk hutch on top creates little cubbies for you to store papers, notebooks, or tools you may need throughout the day. There's even a bench on the bottom for you to put your feet up during the last few hours of the workday.

Buy it: Amazon

2. CubiCubi 40-inch Home Office Table; $95

CubiCubi/Amazon

For those looking for a sleek, modern desk that doesn't skimp on function, go for the CubiCubi. The metal frame, combined with the black wood surface, gives this table a sturdy, reliable feel. There's also a built-in side pocket to store all your papers out of eyesight but within arm’s reach. And according to the company, the whole thing should only take 10 minutes to assemble.

Buy it: Amazon

3. Coleshome 31-inch Computer Desk; $84

Coleshome/Amazon

This 31-inch desk from Coleshome is the perfect option for a small home office. Complete with adjustable leg pads for added stability, this desk can fit in any nook and is designed with simplicity in mind.

Buy it: Amazon

4. Mr. Ironstone Black L-Shaped Desk; $130

Mr. IRONSTONE/Amazon

This unique L-shaped desk is perfect for anyone looking to fit their workstation into the corner of a room. Measuring at 50.8 inches on both sides, you’ll get the most out of your surface by adding multiple monitors, a printer, and books all around.

Buy it: Amazon

5. Furinno Efficient Home Desk with Side Shelves; $53

Furinno/Amazon

If you want to make your office feel more like a study, then you’ll need somewhere to store all your tomes. This Furinno desk can help you make space to work and house all your favorite books nearby to grab whenever you need them. The multilevel shelves help make this desk feel more modern, while also creating plenty of storage space.

Buy it: Amazon

6. JOISCOPE 40-inch Computer Desk; $110

JOISCOPE/Amazon

This desk comes packed with plenty of storage space for your things while also providing a large, sleek worktop for you to spread out all day long. The oak finish on top also adds a bit of sophistication to your workday, even if you spend your lunch break perusing the latest cat memes.

Buy it: Amazon

7. Seville Classics Ergonomic Mobile Desk Cart; $44

Seville/Amazon

Standing desks have become more popular in recent years as people look for more ways to improve their posture and overall health. The Seville Ergonomic Mobile Desk can help you achieve your physical goals while assisting you with your work. The desk's height can be adjusted from 20.5 inches to 33 inches, and it has four swivel wheels, two of which lock in case you want to stay in one spot.

Buy it: Amazon

8. ComHoma Black Writing Computer Desk Office Folding Table; $100

ComHoma/Amazon

For a modern design, there's the ComHoma writing desk. The sleek metal bars on the sides and back of the desk add style, not clutter, and the 39-inch tabletop will give you ample space to work on whatever projects come your way.

Buy it: Amazon

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Why Can’t You Smell Your Own Breath? There Are a Few Theories

Hands are built-in tools for detecting bad breath.
Hands are built-in tools for detecting bad breath.
SIphotography/iStock via Getty Images

The fact that we rarely catch a whiff of our own breath seems fishy. For one, our noses are only a philtrum’s length away from our mouths. We also don’t have any trouble inhaling other people’s stale carbon dioxide, even with a solid few feet between us.

Though we don’t yet have a decisive scientific explanation for this olfactory phenomenon, there’s no shortage of promising theories. According to BreathMD, it could be that we became so accustomed to smelling our own breath that we simply don’t notice its odor anymore—similar to the way we can’t detect our own "house smell." This kind of habituation doesn’t just inure us to unpleasant aromas, it also leaves our noses free to focus on unfamiliar odors in our environment that could alert us to danger.

As HowStuffWorks reports, another hypothesis suggests that we’re more conscious of other people’s halitosis because breath released when speaking is different than breath released when exhaling regularly. All the tongue movement that happens when someone talks could push odors from the back of their mouth out into the air.

But if that’s true, it seems like you’d be able to smell your own breath—at least when you’re the one doing the talking. Which brings us to the next and final theory: That your bad breath dissipates before you get a chance to inhale it. When someone else exhales, you’re inhaling their air almost simultaneously. When you exhale, on the other hand, you have to wait until you’ve reached the very end of your expiration before breathing back in again. By that time, the malodorous particles may have already dispersed.

Even if you’re blissfully unaware of how your own breath smells, it could be a little nose-wrinkling for others—here are some tips for getting rid of halitosis.