Why Do Some Farts Stink and Some Farts Don't?

Chloe Effron
Chloe Effron

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Everyone farts, every day. But not all farts are the same. Some farts make no sound but are really stinky. Others are loud but don't smell. Some you can smell clear across the room, but others you can let out without anyone noticing. (Secret: I’m farting right now!)

The smell of your booty bomb depends on what you’ve been eating. Broccoli, cabbage, onions, eggs, and meat all contain a lot of sulfur, a chemical that helps give rotten eggs their stink. When your body digests, or breaks down, those foods, the teeny-tiny creatures in your gut called bacteria feast upon the proteins in the food that contain sulfur. This process creates smelly gases like methanethiol (METH-ain-THIGH-all). When those gases leave your body, they end up as pungent farts.

All smells are chemicals in the air that your nose can pick up. Farts are made up of chemicals like oxygen, nitrogen, hydrogen, methane, carbon, and the super villain of stinkiness: sulfur. (Sulfur is the reason that skunk spray smells so gross!) The more sulfur in your toots, the more likely they are to clear the room. You also swallow air as you eat or talk. Some of that comes out of your rear end too.

Let's talk about bacteria again. When you eat carbohydrates (CARB-oh-HIGH-drates) like potatoes, bread, and vegetables, your stomach doesn’t fully digest them. They pass into the small intestine and then the large intestine, which are really long tubes leading to your anus (where poop and farts come out). Bacteria break the carbohydrates into smaller pieces. That releases gases like hydrogen and carbon dioxide. Those gases don’t smell. But other bacteria in the gut take those odorless chemicals and make them into compounds (mixes of chemicals) that do smell. Hydrogen sulfide (HIGH-dro-jen SULL-fide) is the smelliest of the gases that might come out of your butt.

For more fart science, check out AsapSCIENCE’s illustrated video explanation of why your farts don’t smell as bad as other people’s do. 



Amazon's Under-the-Radar Coupon Page Features Deals on Home Goods, Electronics, and Groceries

Stock Catalog, Flickr // CC BY 2.0
Stock Catalog, Flickr // CC BY 2.0

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

Now that Prime Day is over, and with Black Friday and Cyber Monday still a few weeks away, online deals may seem harder to come by. And while it can be a hassle to scour the internet for promo codes, buy-one-get-one deals, and flash sales, Amazon actually has an extensive coupon page you might not know about that features deals to look through every day.

As pointed out by People, the coupon page breaks deals down by categories, like electronics, home & kitchen, and groceries (the coupons even work with SNAP benefits). Since most of the deals revolve around the essentials, it's easy to stock up on items like Cottonelle toilet paper, Tide Pods, Cascade dishwasher detergent, and a 50 pack of surgical masks whenever you're running low.

But the low prices don't just stop at necessities. If you’re looking for the best deal on headphones, all you have to do is go to the electronics coupon page and it will bring up a deal on these COWIN E7 PRO noise-canceling headphones, which are now $80, thanks to a $10 coupon you could have missed.

Alternatively, if you are looking for deals on specific brands, you can search for their coupons from the page. So if you've had your eye on the Homall S-Racer gaming chair, you’ll find there's currently a coupon that saves you 5 percent, thanks to a simple search.

To discover all the deals you have been missing out on, head over to the Amazon Coupons page.

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The Northern Lights Storms Are Getting Names—and You Can Offer Up Your Suggestions

A nameless northern lights show in Ylläs, Finland.
A nameless northern lights show in Ylläs, Finland.
Heikki Holstila, Flickr // CC BY-ND 2.0

While all northern lights are spectacular, they’re not all spectacular in the same way. Aurora borealis, or “northern dawn,” occurs when electrons in the magnetic field surrounding Earth transfer energy to oxygen and nitrogen molecules in the atmosphere. The molecules then emit the excess energy as light particles, which create scintillating displays whose colors and shapes depend on many known and unknown factors [PDF]—type of molecule, amount of energy transferred, location in the magnetosphere, etc.

Though the “storms” are extremely distinct from each other, they haven’t been named in the past the way hurricanes and other storms are christened. That’s now changing, courtesy of a tourism organization called Visit Arctic Europe. As Travel + Leisure reports, the organization will now christen the strongest storms with Nordic names to make it easier to keep track of them.

“There are so many northern lights visible in Arctic Europe from autumn to early spring that we started giving them names the same way other storms are named. This way, they get their own identities and it’s easier to communicate about them,” Visit Arctic Europe’s program director Rauno Posio explained in a statement.

Scientists will be able to reference the names in their studies, much like they do with hurricanes. And if you’re a tourist hoping to check out other people’s footage of the specific sky show you just witnessed, searching by name on social media will likely turn up better results than a broad “#auroraborealis.”

Visit Arctic Europe has already given names to recent northern lights storms, including Freya, after the Norse goddess of love, beauty, and fertility, and Sampo, after “the miracle machine and magic mill in the Finnish national epic poem, ‘Kalevala.’” A few other monikers pay tribute to some of the organization’s resident “aurora hunters.”

But you don’t have to be a goddess or an aurora hunter in order to get in on the action. Anybody can submit a name (along with an optional explanation for your suggestion) through the “Naming Auroras” page here. It’s probably safe to assume that submissions related to Nordic history or culture have a better chance of being chosen, but there’s technically nothing to stop you from asking Visit Arctic Europe to name a northern lights show after your dog.

[h/t Travel + Leisure]