Scientists seeking gut insights are attaching flatulence sensors to volunteers' underwear

Farts are tiny status reports from our gut microbiome, with American adults typically passing gas more than 30 times daily.

On the benefits of 'fart walks'

Walking has proven benefits for flatulence by kickstarting the process of peristalsis in the bowels and facilitating easier farts and burps. The timely exercise is also correlated with weight loss (as well as potentially reduced opportunities for social embarrassment).

What's next for gut microbiome science?

A Stanford microbiologist explores what we don't yet know about the gut microbiome—such as whether we can engineer the bacterial species within it—and the current scientific advances in the field.

Explore the chemistry of undesired body odors

This graphic highlights some of the main compounds in different body odors, including halitosis (bad breath), flatulence, and foot odor.

Scientists determine the smells of objects in outer space

Using spectrographic techniques, scientists determine the chemical composition of planetary atmospheres, comets, and other objects in space. Combining these chemicals in labs on Earth has revealed locations in space that smell like nail polish remover, rotten fish, and urine.

Humans can track smells on the ground quite well—our ability to crawl is a limiting factor

As part of a scientific bet, neurobiology researchers dragged a chocolate bar across the grass and sought to see if a human could track it—she could. This led to a more in-depth experiment on human olfactory capabilities and behavior when other senses were blocked.

In 2026, University of Cambridge researchers reported that a group of gut bacteria called CAG-170 may be a key marker of good health, occurring far more often in healthy individuals and less commonly in people with chronic diseases.

Odor blockers use nonpolar oils to trap smelly polar molecules

In the case of feces, gut bacteria produce compounds such as skatole and hydrogen sulfide, which the brain registers as unpleasant. Because oils do not dissolve in water, they can be used to create a layer on the surface that prevents smelly compounds underwater from escaping into the air.

Researchers generally group gut bacteria into six different categories, with varying amounts of these microbes residing in different parts of the digestive tract.

Benjamin Franklin once wrote a satirical essay about passing gas

The Founding Father was asked to judge a contest for the Royal Academy of Brussels, but was incensed by one of the contest's questions, which he believed was highly impractical. In response, he wrote a piece suggesting that the most essential problem for scientists to solve was the "fetid Smell" that came with passing gas.

Listen to how the gut microbiome influences your emotions

The gut-microbiome connection may involve the enteric nervous system, a collection of hundreds of millions of neurons throughout the gut that transmit signals up the vagus nerve to the brain.

Fecal transplants can help treat infections by transplanting healthy gut bacteria from a donor into a patient's gastrointestinal tract using samples of human waste, which are turned into a liquid mixture and often delivered via a colonoscopy procedure.

Gut bacteria are evolving and can acquire as many as 100 new genes per year, on average.

'Sweat dating' is a dating approach in which partners select each other based on body odor.

A super-sniffer smelled her husband's Parkinson's disease years ahead of symptoms.

A stand-in 'nose' may help people with anosmia to smell certain odors

In a 2025 paper, researchers reported they'd created a proof-of-concept device that bypasses typical olfactory pathways and instead exploits an alternative—the trigeminal nerve in the nose—to detect a few strong scents. The nerve typically helps detect the temperature of inhaled air or the presence of irritants. (Some users may experience a paywall.)

Vitamin B1 is linked to gut motility—helping fight constipation—in 2026 research

A study published in early 2026 found a link between vitamin B1 and the successful movement of food through your GI tract, known as gut motility. The work incorporated genetic and survey data about poop frequency to identify genes associated with gut motility and then separately linked poop frequency data with how much vitamin B1 people ingested, theorizing that the vitamin supports the production of acetylcholine, a neurotransmitter that stimulates GI system contractions.

Trillions of bacteria, viruses, fungi, protists, and archaea live in our guts, producing a wide range of molecules, hormones, and more—underscoring the immune system's pivotal role in the microbiota-gut-brain axis.

A dog's nose can be up to 100,000 times more sensitive than a human's, and each possesses a secondary organ for smelling, which helps learn about other dogs when they sniff each other's butts.

The reason some people love exercise may be because of their microbiome

Certain gut microbes in mice trigger dopamine release and drive motivation to exercise more. Scientists are investigating whether humans carry similar microbial patterns that influence our natural inclination towards movement, exploring how unseen microbial ecosystems may shape mammalian fitness behavior and reinforce innate reward pathways. (Some users may experience a paywall.)

Specific gut microbiome 'fingerprints' are associated with cancer recurrence, with up to 94% accuracy.

A 'fishy' scent does lead to mistrust

In experiments where people were exposed to a literal fishy smell they were less willing to cooperate with others in economic games requiring trust, but that wasn't the case when they were exposed to another bad odor—the smell of flatulence.

See how the gut and the brain communicate through a bundle of nerves running from the brain to the digestive tract, serving as both a physical and chemical link.

Humans have taste receptors throughout the body, including in the testes and lungs, but we don't taste what they detect because those areas lack taste buds.

Despite privacy risks, scientists are using DNA in the air to assess ecosystem health

While DNA in soil and water samples has long been used for such analyses, airborne DNA is being incorporated into such efforts to monitor individual species abundance, detect invasive species, measure biodiversity, and determine the success of conservation actions. Future work may include detecting attacks from biological weapons.

Gut microbiome experiments involving transfers of gut microbes from depressed people to rodents indicate that the rodents may then display depression-like symptoms.

Bacteria in our intestine influence the brain via the gut-brain axis.

A technical review of what researchers know about the gut microbiome

This overview from the National Institutes of Health provides a deeper (but still accessible) look at the different bacteria in the gut, how the microbiome develops through life, its purpose, and more.

Scientists monitor volcanoes with a suitcase-sized observatory called SKATE

Short for Setup for the Kinematic Acquisition of Explosive Eruptions, the device is left to record heat, sound and visual data while volcanologists remain at a safe distance. The $58,000 tool is the successor to the FAMoUS (Fast Multiparametric Setup) prototype.

Bacteria have been genetically engineered to bioluminesce when wine has spoiled

Developed by researchers at Hebrew University, the method involves the firefly enzyme luciferase, which emits light from within bacteria expressing when they are in the presence of acetic acid vapors produced by wine. The process provides affordable, on-site, real-time monitoring of fermentation quality.

Scientists are experimenting with ways to probe the multiverse theory

Researchers are simulating vacuum bubbles—the theorized starting points of universes—using quantum computers, digital models, and exotic lab setups to study how they form, expand, and possibly collide. One experiment aims to "blow" artificial universe-like bubbles inside ultra-cold quantum gases, potentially capturing real-time glimpses of cosmic birth processes in a lab.

Read the academic article explaining how ancient smells can be dissected and recreated

This paper explores how biomolecular data on past scents can be teased out and then transformed into olfactory museum experiences, adding another component to our understanding of archaeology.

What is the gut microbiome?

The gut microbiome is a microscopic ecosystem that runs off the work of microbes in the digestive tract. These workers make getting energy from food possible. What and how that energy manifests depends on what building blocks these microbes have to work with, meaning their composition and functions are strongly influenced by diet. Gut microbes have their own genes, which affect how a person's genes act.

Gut microbiome rewrites may help reduce allergies

Researchers are investigating different strategies to determine if one day they could give people a combination of gut microbes to set them up for fewer allergies. In animal research, scientists have already prevented severe allergic responses in allergy-prone mice—supplying them with gut microbes from healthy, non-allergic human babies.

Scientists now know why wombats poop cubes

For years, scientists have been wondering why wombat poop is cube-shaped (yes, really). Now, they say they have got to the bottom of the mystery.

Listen to recordings of different fish species

Scientists have captured and curated this collection of species-specific recordings, helping us gain a deeper understanding of underwater ecosystems. Uncover their sounds, which include a lot of thumps, burps, and grunts.

The men’s underwear index predicts recessions based on men’s underwear sales

Internet users have been using some nontraditional indicators to predict whether a recession is imminent, including the return of so-called “recession pop.”

An anthropologist spent years riding garbage trucks to understand what our trash says about us

Robin Nagle rode with New York City sanitation workers to trace the hidden life of what we throw out. Her research explores what the things we discard reveal about who we are. 1440 explores the hidden life of trash.

The gut microbiome—a complex community of up to 100 trillion microbes—has a changing composition, influenced by our life stage, diet, medications, environment, and other factors.

Some research suggests that the gut microbiome influences our risk of heatstroke, with elevated exercise levels raising body temperature to unsafe levels and increasing gut permeability—causing a "leaky" gut.

Visualize the different parts of the digestive tract, a roughly 30-foot tube which runs from our mouths to our rear.

Explore an interactive visualization of greenhouse gas emissions from 745 million sources worldwide.

Tokyo's transparent toilets use smart, automatic glass to make cleanliness visible

Dubbed the Tokyo Toilet project, this initiative installs restrooms whose walls are transparent when empty, so users can see whether they are clean and safe. When they lock, they turn opaque for privacy. Beyond addressing two key anxieties (hygiene and security), the project lends a distinct architectural prestige to typically banal (and reviled) toilets.

Can the gut microbiome drive addiction?

New research suggests an imbalance of gut microorganisms may influence the likelihood of addiction and addictive behaviors by increasing the severity of withdrawal symptoms, triggering brain inflammation in regions of impulse control, and more.

Dogs smell a lot of stuff we can't, including bed bugs and chemicals in electronic devices

In addition to identifying medical smells and tiny insects like bed bugs, dogs can also detect electronic storage devices. These tools often contain triphenylphosphine oxide, a chemical used to prevent overheating.

Landfills capture methane gas and convert it into usable energy

As organic waste breaks down underground, it produces landfill gas that is roughly 50% methane. That gas can be captured and used to generate electricity or provide heat for nearby homes and businesses.

A doctor answers the internet's burning questions about the gut

Gastroenterologist Dr. Ugo Iroku answers the internet's burning questions about digestion and bowel movements. Get the lowdown on what it means when your stuff is super dark, the impact of coffee on evacuating bowels, and much more.

Thunderquakes—seismic waves created when lightning strikes the ground—have enabled scientists to image underground environments near Earth's surface by detecting vibrations along subterranean fiber-optic cables.

The most unique-smelling places on Earth

Have you ever picked a travel destination by smell? This Atlas Obscura piece cultivates a list of the most distinct-smelling spots in the world. Learn about these obscure scents to potentially book a trip to a spring that smells like rotten eggs, or a desert valley filled with frankincense trees.

How fecal transplants work

1,700 years ago, Chinese alchemist Ge Hong was renowned for his soup that could cure diarrhea-stricken patients. It had a surprising secret ingredient: feces. While it might seem unwise to consume feces, exciting new research suggests that taking...