The short answer: there are no proven health benefits to smelling farts

Farts are mostly nitrogen, oxygen, carbon dioxide, and hydrogen — gases your body produces naturally during digestion. A small amount of the smell comes from compounds like hydrogen sulfide and methane. While these gases are harmless in the tiny amounts present in a fart, there is no scientific evidence that inhaling them provides any medical benefit.

The idea that fart-smelling might be good for you has circulated online and in popular media, often based on a misreading of a single 2016 study. That study looked at hydrogen sulfide in controlled laboratory doses, not farts. It found that very small amounts of hydrogen sulfide might help cells under stress in a petri dish — a finding so preliminary that it has not led to any human treatments or recommendations.

Key Takeaways

  • Farts contain mostly harmless gases, but no research shows that smelling them offers health benefits to humans.
  • A widely shared claim about fart-smelling comes from misreading a laboratory study about hydrogen sulfide in controlled doses, not actual farts.
  • Hydrogen sulfide in farts is present in amounts far too small to have any biological effect on your body.
  • If you are interested in gas-related digestive health, talking to a doctor about bloating, gas, or digestive discomfort is a more useful step than seeking benefits from farts themselves.

Where the "fart benefits" claim comes from

In 2016, researchers at the University of Exeter published a study showing that hydrogen sulfide — a compound produced by bacteria in the gut — might protect cells from damage in laboratory conditions. The study was conducted in petri dishes, not in living humans or animals. The researchers were exploring whether hydrogen sulfide might one day lead to new treatments for diseases like arthritis or dementia.

News outlets and social media simplified this finding into "smelling farts is good for you," which is not what the research showed. The study did not involve farts, did not test whether inhaling farts helps anything, and did not suggest that people should smell farts for health reasons. The researchers themselves have said their work has been misrepresented online.

Why the amount of hydrogen sulfide in farts is too small to matter

Even if hydrogen sulfide were beneficial in controlled doses, the amount in a fart is negligible. A fart is roughly 99% nitrogen, oxygen, carbon dioxide, and hydrogen. The remaining 1% includes trace amounts of hydrogen sulfide and other compounds — concentrations so low that they would have no measurable effect on your body.

For comparison, the laboratory studies that found any effect from hydrogen sulfide used carefully measured doses in controlled environments. Your body is also constantly producing small amounts of hydrogen sulfide on its own during normal digestion. There is no evidence that adding more from external sources — farts or otherwise — changes anything.

What actually happens when you smell a fart

When you smell a fart, you are detecting volatile organic compounds that your nose can sense at very low concentrations. Your olfactory system is extremely sensitive, which is why farts smell noticeable even though the actual chemical content is tiny. Smelling something, however, does not mean it is entering your bloodstream or affecting your cells in any meaningful way.

The smell itself is harmless. Farts are not toxic, and breathing them in will not poison you or make you sick. But the absence of harm is not the same as the presence of benefit. Many things are safe to smell without being good for your health.

Real reasons people have digestive gas

If you are thinking about farts because you produce a lot of gas or experience bloating, the issue is usually related to what you eat, how fast you eat, or how your digestive system processes food. Common causes include eating foods high in fiber, swallowing air while eating, lactose intolerance, or certain digestive conditions.

If gas and bloating are bothering you, a doctor or registered dietitian can help you figure out what is causing it and suggest real changes — like adjusting your diet, eating more slowly, or ruling out underlying conditions. These approaches have actual evidence behind them, unlike fart-smelling.

The difference between internet claims and medical research

Health claims that spread online often start with a grain of truth — in this case, a real study about hydrogen sulfide — and then get stretched far beyond what the research actually showed. By the time a claim reaches social media, it may have been simplified so much that it no longer reflects the original findings.

When you see a health claim online, it helps to ask: Was this tested in humans or only in a lab? Did the study test the actual thing being claimed (farts), or something related to it (hydrogen sulfide in controlled doses)? Are there follow-up studies, or just one preliminary finding? In the case of fart-smelling, the answers are no, no, and no.

Frequently Asked Questions

Is hydrogen sulfide in farts actually harmful?

No. The amount of hydrogen sulfide in a fart is so small that it poses no risk to your health. You are exposed to more hydrogen sulfide from other sources in daily life, like certain foods and industrial areas, without any effect.

Did the 2016 study actually recommend smelling farts?

No. The study was laboratory research into whether hydrogen sulfide might help cells in a petri dish. The researchers did not test farts, did not involve humans, and did not suggest any health practice. The connection to fart-smelling came from media misreporting.

Could there be benefits we just haven't discovered yet?

Anything is theoretically possible, but there is no current evidence or active research suggesting that smelling farts provides health benefits. If researchers were interested in hydrogen sulfide as a treatment, they would study it in controlled doses in human trials — not recommend that people smell farts.

What should I do if I have a lot of gas or bloating?

Talk to your doctor or a registered dietitian. They can help identify whether your gas is related to diet, eating habits, food sensitivities, or an underlying digestive condition. Real solutions might include dietary changes, eating more slowly, or testing for conditions like lactose intolerance.