Don’t sleep on taking some crap

 

# Don’t Sleep on Taking Some Crap: Can Fecal Transplants Really Help People With Insomnia?

**The claim:** “Poop transplants could help insomniacs sleep better.”

**Verdict: Promising, but not proven as a standard treatment.**

The headline sounds like something designed to make people stop scrolling.

And, admittedly, it works.

The idea that swallowing capsules containing microbes derived from human stool could help someone sleep through the night sounds bizarre enough to be a joke. Yet in 2026, researchers have produced some of the most intriguing human evidence so far that the bacteria living inside our intestines may influence how well we sleep.

A randomized, double-blind, placebo-controlled clinical trial involving 80 adults with chronic insomnia found that a fecal microbiota transplantation, or FMT, treatment protocol was associated with substantial improvements in objective measures of sleep. The study was published in the *Journal of Internal Medicine* in July 2026.

But there is an important catch.

This does **not** mean doctors now recommend “poop pills” as a routine insomnia cure.

It does not mean anyone should attempt a homemade fecal transplant.

And it certainly does not mean that every person who cannot sleep should start looking for a stool donor.

The research is exciting precisely because it opens a door—not because scientists have already walked through it.

Here is what the evidence actually shows.

## The strange question scientists are asking

Insomnia has traditionally been discussed in terms of the brain.

Stress.

Anxiety.

Circadian rhythms.

Medications.

Lifestyle.

Depression.

Chronic pain.

Sleep apnea and other medical conditions.

But over the past several years, researchers have increasingly focused on another part of the body: the gut.

Inside the human digestive tract lives a vast ecosystem of bacteria and other microorganisms collectively known as the gut microbiome.

These organisms are not simply passengers.

They interact with the immune system, produce biologically active compounds, influence metabolism and communicate with other systems throughout the body.

One of the most fascinating possibilities is that the gut and brain communicate in both directions through what scientists often call the **gut-brain axis**.

That raises a provocative question:

Could changes in the gut microbiome contribute to disturbed sleep?

And if they can, could changing those microbes improve sleep?

The 2026 FMT trial was designed to investigate exactly that possibility.

## What is a fecal microbiota transplant?

The phrase “fecal transplant” sounds deliberately outrageous in a headline.

The medical terminology is much more precise: **fecal microbiota transplantation**, or FMT.

The basic concept is to transfer microorganisms from screened donor stool into another person's digestive system.

The objective isn't to give someone “poop” as a nutritional substance.

The objective is to introduce a community of microorganisms.

In the new insomnia trial, researchers used specially prepared capsules containing microbial material derived from carefully selected healthy donors.

Participants who received the experimental treatment first underwent a short antibiotic regimen intended to reduce some of their existing intestinal bacteria. They then swallowed FMT capsules, followed by a booster dose two weeks later.

That distinction matters.

When people see a headline saying that “poop pills” improved insomnia, it is easy to imagine that the stool itself was somehow acting like a sleeping medication.

That isn't what scientists believe.

The hypothesis is that **microorganisms and the biological substances they produce** may influence physiological systems involved in sleep.

## The 80-person experiment

The new study involved 80 adults with chronic insomnia recruited from seven hospitals in China.

Researchers divided the participants into two groups.

Forty received the FMT-based treatment protocol.

Forty received placebo treatment.

The study was randomized and double-blind, meaning the allocation was designed so that participants and researchers were not supposed to know who received the active treatment during the trial.

This is important because randomized, placebo-controlled studies provide much stronger evidence than anecdotal reports.

Researchers also didn't simply ask participants, “Did you sleep better?”

They used **polysomnography**, an overnight sleep study that can monitor brain activity, eye movements, heart rate, oxygen levels, breathing and other physiological signals.

That gave investigators an objective way to examine changes in sleep.

And this is where the story becomes genuinely interesting.

## Sleep efficiency jumped dramatically

One of the most striking findings involved **sleep efficiency**.

Sleep efficiency is essentially the percentage of time spent in bed that a person actually spends asleep.

In the FMT group, average sleep efficiency increased from approximately **79% before treatment to 93% one month later**.

The placebo group changed only slightly, from approximately **85% to 87%**.

That is a substantial difference.

Imagine spending eight hours in bed but repeatedly waking, tossing and turning, or remaining awake for long periods.

The clock says you spent eight hours in bed.

Your body may have experienced something very different.

Improving sleep efficiency means more of that time is actually spent sleeping.

The researchers also found a striking change in the amount of time participants remained awake after initially falling asleep.

In the FMT group, this measure dropped from roughly **79 minutes to 17 minutes**.

In the placebo group, it moved in the opposite direction, from approximately 37 minutes to 42 minutes.

Those numbers are among the reasons the study attracted so much attention.

But they are also exactly why the findings need to be interpreted carefully.

## What happened after the first month?

The story doesn't stop at the sleep laboratory.

Participants receiving FMT continued reporting improvements in their insomnia symptoms during follow-up assessments extending from two to six months.

That durability is potentially important.

Many sleep interventions can produce short-term improvements.

The more interesting question is whether an intervention changes something underlying the problem.

If altering the microbiome can produce lasting changes in sleep, researchers will want to understand why.

However, subjective improvement during follow-up is not equivalent to proving that the treatment provides a long-term cure.

Six months is not the same as several years.

And a study involving 80 people is not large enough to establish how broadly the findings apply to the millions of people worldwide who experience insomnia.

## The biggest problem with the headline

Here's where the viral claim needs a correction.

The headline suggests:

**Take a poop transplant and sleep better.**

The actual scientific conclusion is much narrower.

Researchers tested an **FMT-based treatment protocol** in a small randomized trial.

The treatment included antibiotics before the FMT.

Therefore, it is impossible to say from this study alone that the improvement came entirely from the transplanted microbiota.

The antibiotics themselves can dramatically alter the gut microbiome.

They could potentially influence symptoms independently or help create an environment in which the transplanted microorganisms establish themselves.

That means researchers still need to determine exactly which component is responsible for the improvement.

Was it the antibiotics?

The donor microbes?

The combination?

A specific bacterial population?

Changes in microbial metabolites?

Or a chain reaction involving the immune system and nervous system?

The study cannot fully answer those questions.

## The gut-brain connection

This is where the science becomes even more fascinating.

The gut and brain are connected through several biological pathways.

The nervous system is one.

The immune system is another.

Hormonal and metabolic signaling also matter.

Gut microbes can produce or influence compounds that participate in biological processes throughout the body.

Researchers are therefore investigating whether changes in the microbial community can affect systems involved in stress responses, inflammation and sleep-wake regulation.

The 2026 study provides evidence consistent with that hypothesis.

But “consistent with” is not the same thing as “proven.”

This distinction is critical.

A person may have insomnia and an altered gut microbiome.

That doesn't automatically mean the microbiome caused the insomnia.

It could work in the opposite direction.

Poor sleep can influence eating patterns, stress hormones, physical activity, metabolism and other factors that may themselves affect gut bacteria.

So scientists face a classic biological puzzle:

**What came first?**

The disrupted sleep?

Or the disrupted microbiome?

Possibly both.

## Another 2026 study adds an intriguing clue

The evidence did not stop with the main clinical trial.

A separate exploratory analysis published in *Postgraduate Medicine* examined autonomic nervous system changes within the same randomized trial.

The study included the same 80 participants, with 40 receiving FMT and 40 receiving placebo.

Researchers looked at heart-rate variability measures as indicators of autonomic regulation.

They found that FMT significantly reduced the LF/HF ratio, a heart-rate-variability measure used in their analysis of autonomic balance.

The researchers also reported that the change was associated with longer total sleep time.

Their mediation analysis estimated that the autonomic change statistically accounted for approximately 49.7% of the FMT-associated effect on total sleep time.

That is intriguing.

It suggests a possible pathway connecting the gut microbiome to sleep through autonomic regulation.

But again, the word **possible** matters.

This was an exploratory analysis.

It does not prove that altering the autonomic nervous system is the mechanism responsible for the improvement.

The authors themselves said further research is needed to establish the durability and clinical significance of these findings.

## The microbiome itself changed

Researchers also observed changes in the gut microbial community after the intervention.

The FMT treatment produced microbial remodeling, with changes involving several bacterial groups.

The exploratory autonomic analysis reported enrichment of organisms including *Lachnospira eligens*, the Christensenellaceae R-7 group, Ruminococcaceae and *Coprococcus*, alongside reductions in *Prevotella copri*, *Streptococcus* and *Faecalibacterium*.

The significance of these changes is not yet completely understood.

It would be a mistake to look at a list of bacteria and declare that one is a “sleep bacterium.”

The microbiome is an ecosystem.

Changing one group can affect other organisms and the chemicals they produce.

Scientists therefore need larger studies that combine microbiome sequencing with measurements of metabolites, inflammation, hormones, neural activity and detailed sleep outcomes.

That could eventually help answer a much more important question:

**Which microbes, if any, actually matter for sleep?**

## This isn't the first clue

The 2026 trial didn't appear out of nowhere.

Earlier research had already suggested a relationship between gut microbiota and insomnia.

A 2023 real-world study published in *Frontiers in Microbiology* examined adults who had undergone FMT for various chronic diseases.

Among 33 enrolled participants, 17 were classified as having chronic insomnia.

Researchers reported improvements in insomnia-related questionnaire scores following FMT and observed changes in several bacterial groups.

But that study had a major limitation.

It was observational rather than a large randomized placebo-controlled trial.

That means researchers could observe an association, but they couldn't establish the same level of causal confidence.

The new 2026 randomized trial therefore represents an important step forward.

It doesn't settle the question.

But it makes the question much harder to ignore.

## FMT is already a real medical treatment—but for something else

Another reason the insomnia story can be confusing is that fecal microbiota products are not purely experimental medicine.

FMT-related treatment has already entered mainstream medical care for certain conditions.

In 2023, the U.S. Food and Drug Administration approved **Vowst**, an orally administered fecal microbiota product.

But there is a crucial detail:

Vowst is approved for preventing recurrence of *Clostridioides difficile* infection in adults after antibacterial treatment for recurrent infection.

It is **not approved as a treatment for insomnia**.

The FDA reported that, in its randomized study, recurrence of *C. difficile* infection through eight weeks was lower among Vowst recipients than placebo recipients—12.4% compared with 39.8%.

This represents an important milestone in microbiome medicine.

It shows that manipulating the intestinal microbial ecosystem can have genuine therapeutic value.

But it also demonstrates why scientists have to be careful.

A treatment that works for recurrent *C. difficile* cannot automatically be assumed to work for insomnia.

Different diseases involve different biological mechanisms.

## And FMT is not risk-free

This is perhaps the most important part of the entire story.

The phrase “poop pills” can make the treatment sound harmless.

It isn't.

The FDA has warned about the possibility of transmitting infectious organisms through FMT.

In 2019, the agency reported serious infections involving multidrug-resistant organisms transmitted through investigational FMT. Two immunocompromised adults developed invasive infections caused by ESBL-producing *E. coli*, and one of those patients died.

In 2020, the FDA also warned about transmission of pathogenic *E. coli* associated with investigational FMT products.

Six patients developed infections involving enteropathogenic or Shiga-toxin-producing *E. coli*; four required hospitalization.

These events don't mean properly screened FMT is inherently dangerous.

They mean that **donor screening, laboratory testing, processing and clinical oversight matter enormously**.

A stool sample contains living microorganisms.

Some are beneficial.

Some are harmless.

Some can cause serious disease.

And researchers are still learning about what else may be transferred.

## So please don't try this at home

The viral nature of this story creates an obvious danger.

Someone suffering from severe insomnia might read about the study and think:

“If researchers can put beneficial bacteria from a healthy person's stool into capsules, perhaps I can do the same thing myself.”

That would be an extremely bad conclusion.

The experimental treatment used in the study involved medical screening, carefully selected donors, controlled processing and a clinical research protocol.

It is not equivalent to obtaining stool from a friend or stranger.

There is no way to determine simply by looking at a healthy person whether their stool contains organisms capable of causing infection.

And there is no safe reason for someone to improvise a fecal transplant based on a news headline.

The FDA's documented safety warnings demonstrate why.

## What about side effects in the insomnia trial?

The results were encouraging from a safety perspective, but the sample was small.

Reporting on the trial indicates that only a small number of FMT participants experienced adverse effects, and those reported effects were mild, including nausea and transient fever.

That is reassuring.

But “no major safety signal in 40 treated people” is not the same as “the treatment is proven safe for everyone.”

Rare complications can be impossible to detect in small studies.

This is one reason larger clinical trials are necessary before any experimental therapy becomes routine.

## Why this matters for millions of people with insomnia

Insomnia is not simply an inconvenience.

Repeatedly failing to obtain adequate sleep can affect concentration, mood, daytime functioning and overall quality of life.

For someone lying awake at 2:00 a.m., watching the minutes crawl toward 3:00 and then 4:00, the problem can feel endless.

That desperation is exactly why new treatments attract attention.

But it is also why evidence matters.

People with chronic insomnia deserve treatments that are both effective and safe.

The 2026 FMT research could eventually contribute to that goal.

But it is much too early to replace established approaches with microbiome transplantation.

## What happens next?

The obvious next step is a larger clinical trial.

Researchers need to reproduce the findings in more people and in more diverse populations.

The original study was conducted in China and involved relatively healthy adults.

That leaves many unanswered questions.

Would the same results occur in older adults?

What about people with obesity?

People taking multiple medications?

People with anxiety or depression?

People with gastrointestinal disorders?

People with sleep apnea?

People with metabolic disease?

Would the treatment work equally well in people from different countries with different diets and microbiomes?

And perhaps most importantly:

**What exactly is the active ingredient?**

If researchers can identify specific bacterial strains, metabolites or microbial communities responsible for the sleep benefit, the future could become much more sophisticated than transferring whole microbial ecosystems.

Instead of a broad FMT treatment, scientists might eventually develop precisely defined microbial therapies.

That would be a very different—and potentially safer—form of microbiome medicine.

## The future may not involve “poop” at all

This is perhaps the most interesting twist.

The headline makes it sound as though the future of insomnia treatment is swallowing human waste.

It probably isn't.

The ultimate goal of microbiome research is not to celebrate feces.

It is to understand the biology contained within the microbiome.

Scientists want to know which organisms matter, what molecules they produce, how they interact with the immune and nervous systems and how those interactions influence disease.

If those mechanisms become clear, researchers may eventually be able to manufacture targeted microbial treatments.

In other words, today's bizarre-looking fecal transplant could be tomorrow's highly engineered microbiome therapy.

Medicine has followed this pattern before.

Something initially crude can reveal a biological principle.

Once scientists understand that principle, they refine it.

## So, is the viral claim true?

**Partly.**

The claim that fecal microbiota transplantation **could help some people with chronic insomnia** is supported by emerging evidence.

A 2026 randomized, double-blind, placebo-controlled study involving 80 adults found significantly improved objective sleep measures following an FMT-based treatment protocol, including a large increase in sleep efficiency and a reduction in time awake after falling asleep. The improvements in self-reported insomnia were reported to persist during follow-up lasting up to six months.

There is also a 2026 exploratory analysis suggesting that changes in autonomic regulation may be involved in the effect.

So this is not a fabricated story.

It is based on genuine scientific research.

But the stronger claim—that fecal transplants are now an established cure for insomnia—is **false**.

The evidence is still preliminary.

The trial was small.

The intervention included antibiotics as well as FMT.

The mechanism remains uncertain.

Long-term safety and effectiveness require additional study.

And FMT for insomnia remains experimental rather than an established standard treatment.

## The bigger story isn't about poop

Perhaps the strangest thing about this entire story is that the stool itself isn't really the star.

The real story is the human microbiome.

For decades, scientists often thought of bacteria as something to eliminate when possible.

Now medicine increasingly recognizes that the body is home to enormous microbial communities that interact with us in complicated ways.

Some microorganisms can make us sick.

Others can protect us.

Some may influence metabolism.

Some may interact with the immune system.

And researchers are increasingly investigating whether the microbiome can affect the brain.

Sleep may be one of the next major frontiers.

The 2026 insomnia trial doesn't prove that the gut controls sleep.

It doesn't prove that every person with insomnia has a microbiome problem.

And it doesn't mean that a stool transplant is ready for your medicine cabinet.

What it does show is something more subtle—and arguably more exciting:

**The biology of sleep may extend farther into the body than scientists once appreciated.**

The bedroom may be where insomnia becomes obvious.

But the story might begin somewhere much farther south.

Inside the gut.

## The bottom line

So, should you “take some crap” before bed?

**Absolutely not—not outside legitimate medical research or an appropriate medical indication.**

Should you dismiss the research as nonsense?

Also no.

The evidence is real, the study was randomized and placebo-controlled, and the results are intriguing enough to justify much more research.

For now, the scientifically honest conclusion is somewhere between the sensational headline and the skeptic's eye-roll.

Fecal microbiota transplantation **may eventually become part of the toolbox for treating certain forms of insomnia**.

But scientists have not yet established who should receive it, which microbes are responsible, how long the benefits last, or whether the treatment can be made consistently safe and effective.

And that final question matters more than the shock value of the headline.

Because medicine isn't ultimately about finding the strangest possible treatment.

It's about finding the treatment that works—and proving that it does more good than harm.

For now, the “poop pill” story is not the end of insomnia research.

It may be the beginning of a much bigger story about the remarkable conversation taking place between our gut and our brain.

And scientists are only beginning to understand what they're saying.