In search of a healthy gut, one man turned to an extreme DIY fecal transplant

Human feces floated in saline solution in a mortar, on a marbled countertop, in a dimly lit kitchen in Burlingame, California. A bottle of ethyl alcohol, an electronic scale, test tubes, and a stack of well-worn pots and pans lay nearby. The stove light illuminated the area as Josiah Zayner crushed the shit with a pestle, creating a brownish-yellow sludge. "I think I can feel something hard in there," he said, laughing. It was probably vegetables — "the body doesn’t break them down all the way."

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This heralded the beginning of Zayner’s bacterial makeover. He was clad in a Wu-Tang Clan T-shirt, jeans, and white socks and sandals. At his feet, James Baxter, Zayner’s one-eyed orange cat, rubbed its flank against its owner’s legs. The kitchen smelled like an outhouse in a busy campground.

Over the course of the next four days, Zayner would attempt to eradicate the trillions of microbes that lived on and inside his body — organisms that helped him digest food, produce vitamins and enzymes, and protected his body from other, more dangerous bacteria. Ruthlessly and methodically, he would try to render himself into a biological blank slate. Then, he would inoculate himself with a friend’s microbes — a procedure he refers to as a "microbiome transplant." Zayner imagines the collection of organisms that live on him — his microbiome — as a suit. As such, it can be worn, mended, and replaced. The suit he was living with, he said, was faulty, leaving him with severe gastrointestinal pain. A new suit could solve all that. "You kind of are who you are, to a certain extent," he said. "But with your bacteria, you can change that."

A full bacterial overhaul like this had never been documented before — in fact, it may have been the first time it had ever been attempted. There was no evidence to suggest it would work, though there was a real risk it could make Zayner life-threateningly sick. That didn’t bother him.

Zayner unwrapped a brand-new syringe and filled its barrel with the brownish liquid. He grabbed one half of a gelatin capsule, pushed the syringe’s plunger, and filled the capsule with the fecal slurry in inconsistent spurts. "Undigested portions of the meal are clogging it," he said. Frustrated, he removed the needle and pushed the plunger again, letting clumpy muck accumulate in the half capsule. But by the time he joined both ends of the pill, the gelatin casing had begun deteriorating in his gloved hands. "I think the liquid is dissolving these fucking capsules," he said.

For a brief moment, Zayner considered throwing his head back and swallowing the feces straight up, like a shooter from hell. But the thought disgusted him, and instead he opened a kitchen drawer and grabbed an inoculating loop, an instrument used by microbiologists to sample microorganisms. He dipped it into the large, poop-filled Ziploc bag on the counter. "We’re going to try this new technique — the ‘stuff and jam,’" he said. The unadulterated shit had a frosting-like texture and didn’t eat through the gelatin; the pill held up. Exhausted from his most recent dose of antibiotics, Zayner took a break. Tomorrow, in a hotel room near the San Francisco International Airport, he planned to start his transformation.

Microbiome pill

Zayner is a punk: his ears are adorned with a row of 10 piercings each, his body is covered in tattoos, and his dark mohawk is topped with a shock of bleached-blonde hair. The haircut, the piercings, and most of the tattoos he did himself. He doesn’t trust others with these tasks, he says. This is a running theme in Zayner’s life.

As a child, Zayner rarely saw doctors — his family, he says, was too poor to pay for visits. Then in college, he got health insurance and finally started going; gastrointestinal pain was making it hard for him to lead a normal life. He was pooping more than four times a day, and severe "attacks" forced him to isolate himself for hours. The doctors visits were expensive and ineffective, he says, and over time, Zayner grew suspicious of physicians. "I’ll take their advice if there’s something I can’t fix myself, but otherwise, if what they say goes against what I know, I’m not going to necessarily believe them or trust them, right?" he says.

That’s not to say Zayner is dubious of science — in fact, he’s a scientist himself. In 2013, he earned a PhD in Biophysics from the University of Chicago and subsequently served as a postdoc researcher at NASA’s Ames Research Center for two years. But the space agency didn’t suit him. "NASA was not what I imagined it to be," he says. It was supposed to be a bastion of innovation, but the experiments he saw performed at NASA were underwhelming. "[There’s] very little work getting done, because people either don’t work, don’t care to work, or because the last time they did any science was 40 years ago," he says.

Microbiome portrait

So in January 2016, Zayner left Ames and turned his attention to two of his own projects: an Indiegogo campaign aimed at providing people with CRISPR kits to alter bacterial DNA, and The ODIN, a business he started in grad school that sells scientific kits and instruments to people who’d like to do experiments at home. Today, The ODIN has four employees who work out of Zayner’s garage. Sustained by orders from schools and hobbyists, The ODIN is doing well, Zayner says: he expects the company’s revenue to reach somewhere between $50,000 and $100,000 this year. On weekends he sometimes teaches free classes on genetic engineering in public lab spaces around San Francisco. In our conversations, Zayner stressed to me the importance of breaking science out of labs and classrooms and making it available to the wider public. "I don’t like titles," Zayner told me. "But I generally refer to myself as a biohacker."

"I don’t like titles," Zayner told me. "But I generally refer to myself as a biohacker."

Leaving the world of conventional science made Zayner happy — and working from home was easier on his gut. Zayner generally has to defecate two to three times before starting his workday, and also after every meal. He claims to have ulcers and irritable bowel syndrome, but he’s a bit hazy on the details of his diagnoses. When pressed, he admits that he doesn't remember what his physician told him in college — he could have IBS or inflammatory bowel disease. And a search through his medical records is inconclusive. "I don’t think I made it up or am remembering wrong, but who knows?" he wrote me in a text.

But his physical distress — and his frustration with the medical treatment he received — was very real. So at 35, Zayner decided to dive into one of science’s most foolhardy traditions: self-experimentation. Some of his predecessors have achieved great things. In 1984, Nobel winner Barry James Marshall ingested a species of bacteria to demonstrate their role in causing ulcers. He was, to his discomfort, proven correct. Other ventures have been less successful. In 1900, an American physician by the name of Jesse Lazear intentionally submitted himself to bites from yellow fever-infected mosquitoes in an effort to learn about the virus’ transmission. He died. Three decades later, Russian physician Alexander Bogdanov performed multiple blood transfusions on himself to deduce whether the procedure would keep him eternally young. It didn’t — the experiment killed him.

Microbiome kitchen wide

Across cultures, human feces are reviled. Shit stinks, yes, but that’s not actually why it’s gross — thanks to its bacterial load, it’s a disease vector that causes outbreaks of cholera, typhoid fever, and E. coli. But humans didn’t truly figure that out until the 19th century. So, for a long time, shit was actually used by some as medicine.

The Ebers Papyrus, a document from Ancient Egypt dating back to 1500 BC, contains more than 50 prescriptions for medicines in which shit is the active ingredient. In the 4th century, a well-known traditional Chinese doctor described using a suspension of human feces to help patients with food poisoning or severe diarrhea. And in the 17th century, an Italian anatomist named Fabricius ab Aquapendente was using shit to treat gastrointestinal diseases in veterinary medicine.

The first modern fecal matter transplant didn’t take place until the mid-20th century. In 1958, an American surgeon named Ben Eiseman performed enemas on four pseudomembranous colitis patients. Eiseman suspected that a treatment of antibiotics had killed off natural gut bacteria, leading to severe cases of diarrhea. So, instead of flushing their colons with water alone, he used shit from healthy patients. Perhaps, he figured, reintroducing normal intestinal bacteria into the guts of patients whose digestive system had been wiped out would heal them. "It seemed to work," Eiseman told author Mary Roach in a 2012 interview. "It made a small splash."

"Sometimes patients can improve in a couple of hours."

The fecal enema didn’t exactly come into fashion — over the next three decades, only a handful of trials were done. But by the late ‘80s, fecal matter transplants were increasingly recognized as a treatment for infections caused by the bacterium Clostridium difficile — infections that can cause colitis. And antibiotics, used more and more often in American health care, were triggering more and more cases of C. diff. By 2011, C. diff infections were killing 15,000 Americans a year. Fecal matter transplants, or FMTs — the procedure that Egyptian and Chinese doctors used long before Eiseman — suddenly made a comeback.

Though enemas and nasal operations are still performed, the most publicized FMT procedure involves taking pills filled with the feces of another healthier individual. Because shit is considered a medicine when it’s administered by a doctor, the procedure is strictly regulated by the US government, and is only available to patients with recurrent C. diff. And in truth, the restriction has a lot do with the fact that scientists don’t yet understand why the treatment works, or how it affects patients in the long-term.

But evidence suggests the benefits can be great: the Mayo Clinic’s campus in Phoenix reports that 90 percent of C. diff patients who receive FMTs are cured of the infection. And the transplants can work fast. "Sometimes patients can improve in a couple of hours," says Majdi Osman, a physician and the clinical program director at OpenBiome, a nonprofit that facilitates fecal transplants by screening donors and collecting their feces.

Microbiome poop

Zayner doesn’t recall the first time he heard about FMTs — and he’s never been diagnosed with C. diff. But given his condition, replacing his gut bacteria sounded like a possible solution. The operation Zayner envisioned, however, would involve more than a simple fecal matter transplant; instead he would also alter the bacterial composition of his nose, mouth, arms, and skin — his entire exterior. He’d been thinking about full-body microbiome transfers for a while: in August 2015 he made a video in which he imagines a future where police use scanners to identify people by their microbiome — a future where "those who engineer themselves are persecuted and imprisoned," he told me.

Last November, I called Zayner to discuss his Indiegogo CRISPR kits and that’s when he mentioned the transplant, which he described as "kind of an art-science project." In the weeks that followed, I reached out to more than a dozen researchers who might be familiar with such an experiment. Eventually, a skin microbiome expert told me that the closest thing scientists had done in adults was to transfer bacteria from one site of the body to another. In that instance, a bacterial transplant from the study participants’ tongues to their forearms held up well eight hours later, but a transfer of tongue bacteria to participants’ foreheads didn’t. The researchers obtained similar results when they attempted the same, small transfers between different volunteers. Other research has been done on inoculating children born through C-section with their mothers’ vaginal bacteria. But I found no mention of an adult ever trying to kill all the bacteria on their skin in order to permanently replace them with that of another human being.

Every single professional stressed that Zayner’s experiment could make him very sick

The lack of precedent meant that few experts were willing to discuss the bacterial skin transfer Zayner was suggesting. One biologist did agree to talk — and she wasn’t impressed. "I think that’s sort of pie in the sky," said Elizabeth Hohmann, a fecal transplant expert at Harvard University. Changing the skin’s microbiome is "not as simple as coating yourself in some antibiotics and then putting a [bacterial] swab on — that’s just ridiculous."

Researchers were even less enthusiastic about the fecal transplant. Of the nine biology and medical professionals I spoke with, every single one stressed that Zayner’s experiment could make him very sick. Zayner vowed not to analyze his donor’s feces — it contradicted, he said, the DIY ethos of the experiment and could make the project seem less accessible to laypeople. As a result, he was putting himself at risk for hepatitis, rotavirus, and a whole slew of other pathogens and parasites. And his decision to take antibiotics to kill his own bacteria before the transplant was risky, said OpenBiome’s Osman. Some people carry C. diff without any symptoms; if Zayner was one those people, disrupting the balance in his gut could enable C. diff to flourish — and the consequences of that could be life-threatening. "We actually advise patients to stop antibiotics before they have a fecal matter transplant, if possible," said Osman.

There was another thing that all the experts agreed on: the chances that Zayner would experience any benefit from the transplant were essentially zero. "We don’t have any evidence whatsoever that fecal microbiota transplantation helps cure other diseases," says Sahil Khanna, a gastroenterologist at the Mayo Clinic. Hohmann added that Zayner’s experiment was ultimately "naïve and poorly advised — on several levels."

microbiome hotel portrait

For months, Zayner mulled over the experiment. Then, at the end of January, he booked three nights at a hotel just south of the San Francisco Airport. The Crowne Plaza sits along Highway 101, the artery that shuttles tech workers back and forth between San Francisco and Silicon Valley. The hotel is a dated and dreary place, decorated in a depressing blend of beiges and browns.

A hotel room is not a sterile environment for the sort of operation Zayner envisioned, but it was better than his home, where traces of his microbiome could be found in his sheets, his bathroom, his kitchen, his front doorknob. Zayner’s next challenge was finding a donor. Everyone he’d spoken to had either turned him down or backed out citing the risks involved.

"If I end up in the hospital, it’s okay; if I end up sick, it’s okay."

A few days before the scheduled procedure, he finally convinced someone to participate: Michael (not his real name), a friend from college who Zayner hadn’t seen in 10 years. Michael knew people with gastrointestinal tract problems, and he thought Zayner’s experiment could help him. So Michael agreed to poop in a Ziploc bag, and have the skin on his arms, legs, the inside of nose, and his mouth swabbed twice. If the experiment worked, Zayner and Michael would share a unique and very personal biological bond.

Fecal matter donors typically undergo a rigorous screening process, says Mark Smith, director of OpenBiome. "Less than 3 percent of all of the donors that we screen end up qualifying as donors." When I reminded Zayner of the dangers involved, he insisted the experiment was worth it. "That’s the risk I need to be able to take to inspire people to take their health in their own hands," he said.

Comments like these took me aback: they demonstrated the intricate ethical acrobatics Zayner was continuously performing. He was convinced that carrying out a risky and unproven procedure — using himself as a human guinea pig — and then publicizing it, could help others. To a skeptic like myself, Zayner’s good intentions came across as misguided.

Would he feel responsible if someone repeated his experiment and fell ill? "No, not at all," he said without hesitation. He had calculated the risks and benefits of his experiment — "If I end up in the hospital, it’s okay; if I end up sick, it’s okay" — and anyone following in his footsteps was responsible for doing the same. "I’m not your parent or government to regulate you; do what you want with your body."

microbiome hotel wide

At 3PM on a Thursday in mid-February — day one of his procedure — Josiah Zayner stood in the middle of his hotel room, stripping down to his boxer briefs. He donned a yellow, disposable isolation gown and blue shoe covers. He handed me a set as well, which I immediately put on.

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Zayner’s first task was to turn the hotel room into a sterile containment field. Thousands of travelers have passed through here: pilots and flight attendants from all over the world, snotty children, flu-ridden businessmen — not to mention countless employees. At one point or another, their microbiomes had colonized this space. Zayner stripped the beds, replacing the sheets with ones he bought from Amazon specifically for this purpose. Then, he grabbed a container of Clorox Wipes and silently disinfected every surface of the room he was likely to touch.

His experimental protocol was self-designed. There were five main steps, two of which he’d already started: taking samples of his skin microbiome and feces for a later analysis; and ingesting a two-day regimen of antibiotics he’d purchased on Alibaba and eBay and verified for effectiveness. Then Zayner would try to rid himself of the bacteria on his body by cleaning his skin with powdered tetracycline, an antibiotic he would also dissolve and use to clean his nostrils and mouth. "Rubbing your skin with tetracycline powder is not going to sterilize it," Elisabeth Bik, a microbiologist at Stanford University, told me. "There is no way to sterilize your skin. Any attempt at complete sterilization of a person’s skin will most likely kill a person first before they are sterile." Once clean, Zayner would proceed to the actual transplant: swallowing poop pills, and applying a saline solution filled with Michael’s skin bacteria to his nose, mouth, arms, and legs. Later, he would sample his skin and fecal matter again.

So far, so good. Zayner had been on a digestive rollercoaster since he began the antibiotic regimen, but that was expected. He was tired and in pain. The drugs gave him cramps, in addition to "explosive poops," he said.

With the room disinfected to his liking, Zayner jumped into the shower to begin scrubbing off his microbiome. As he applied the antibiotic with a kitchen sponge, his pale white skin turned an angry red; he was scrubbing hard. After, he filled a Neti Pot with the same antibiotic liquid and flushed out his nasal passages over the sink — a process that involved hacking up prodigious amounts of yellowish saliva.

I couldn’t help but notice Zayner cutting corners. After drying off, he put on a brand-new Hanes white T-shirt to prevent his old microbiome from recolonizing his body, but an old — though freshly laundered — pair of jeans. He sampled his arms, nose, and mouth, but he didn’t bother to take microbial samples from his genitalia, and didn’t plan on applying Michael’s skin bacteria to his penis or testicles. He told me that there just isn’t much scientific value in gathering that information. Over the course of his experiment, Zayner would only take a third of the poop pills that someone undergoing a standard FMT procedure would, stretched over a longer period of time. When I confronted Zayner about my observations, he was either dismissive, or unaware of a standard FMT protocol.

Scrubbed raw, at around 5PM, Zayner began the transplant. He put on blue gloves, grabbed a glass of water and took a plastic bag filled with poop pills out of the fridge. He was nervous. "You start thinking about like ‘Wow, why do animals eat their own poop or eat other animals’ poop?’ And like, what really are we so scared about with feces?" he’d told me the day before, rationalizing the experiment.

Microbiome series 2-1Microbiome series 2microbiome series 2 3microbiome series 2 4

Zayner looked like he was enjoying himself. The thrill of the experiment — and the idea that he may soon be rid of his digestive issues — propelled him forward. Sitting on the bed, facing the hotel window, he took a few deeps breaths and raised the pill in the air. "YOLO," he said, tossing it into his mouth. It disappeared down his throat, followed by a gulp of water. Over the next three days, he’d repeat this process, ingesting a total of eight poop pills. At one point he inadvertently tasted some of Michael’s shit, which had gotten on the outside of certain capsules. He describes it tasting "a little bitter."

Next, Zayner applied the donor skin bacteria. He removed his T-shirt and unscrewed a test tube filled with saline solution and the cotton inoculating swab that Zayner rubbed on Michael’s arms. He applied the liquid — which should have been teeming with skin bacteria, Zayner told me — liberally on his arms, chest, and legs. Then, he grabbed the swab that had been in Michael’s mouth, and applied it to the inside of his cheeks and onto his gums. He repeated this process with his nose.

At 6PM, one hour after he began the procedure, Zayner was — in theory — covered in Michael’s microbiome. Then came the wait. "The main risk right now is mostly with the pill that I took. If there’s any toxic bacteria that grew on it or anything like that, it could put me in the hospital," Zayner said, settling into his makeshift quarantine.

For the next 60 hours, Zayner hid out in the hotel room, leaving only to buy snacks in the hotel commissary or eat in the hotel restaurant. He didn’t shower, and spent most of his time on his computer or phone. He watched daytime TV and movies — Back to the Future, Furious 7, anything really. His girlfriend Melissa visited him daily, but avoided touching him, and didn’t spend the night. Every few hours, Zayner repeated his protocol: take another pill, reapply Michael’s bacteria, and take samples of his own skin.

On day two, Zayner told me he was feeling great. "I’m so excited and happy," he said, sitting on the hotel bed. "I really feel like I shed something." He admitted it may have been a placebo effect, but his bowel movements had become less frequent, he said, and he felt rejuvenated.

By the morning of day three, Zayner was relaxed. Taking time off from running The ODIN had done him some good, he said, and his stomach was cooperating — he went almost 24 hours without having to use the bathroom. "Yesterday was a really awesome day so I was like ‘Oh, my gosh. It feels really good,’ but then today feels even better than yesterday," he said.

But when he came home the next day, Zayner’s resolve to follow through with the transfer weakened. He had originally intended to keep taking the pills at home for a few more days. But after three days, he was too disgusted. He felt sick just thinking about them.

Three days after the transfer, he reached out to Argonne National Laboratory, a nonprofit lab run by the University of Chicago, to get his samples sequenced. He sent them a total of 77 samples, which included Michael’s donated poop; Zayner’s poop before, during, and after the transplant; as well as samples taken from Michael and Zayner’s nose, mouth, and skin. He even sent in a skin swab from Melissa and myself, as well as skin and fur samples from his two cats — James Baxter and Trypsin — to see if we had inadvertently contaminated the experiment. The sequencing cost about $4,500. The process, Zayner was told, would take six to eight weeks.

Zayner in his room

There’s essentially no research on the long-term effects of fecal transplants, but some scientists are starting to look at the short-term effects. In late April, scientists announced that when patients receive FMTs, the new bacterial strains can survive for at least three months after the procedure. That means one day it might be possible to introduce customized bacteria to fully replace one’s natural gut microbiome. But that hasn’t changed the fact that fecal transplants are reserved to patients with C. diff — and no one else.

Fecal transplants are reserved to patients with C. diff — and no one else

Zayner is unique, but as far as his pain goes, he isn’t alone. Gastrointestinal diseases affect between 60 and 70 million Americans each year, according to the National Institutes of Health. This number includes people with cancer and liver disease, but also individuals with chronic constipation and irritable bowel syndrome — conditions that aren’t deadly, but aren’t necessarily easy to treat, either. So for people, like Zayner, who haven’t found symptom relief through conventional means, turning to feces — the drug that everyone has access to for free — isn’t all that surprising.

Home remedies are nothing new, but in the internet age, information on "cures" that others have tried have become increasingly available. Finding someone who’s willing to walk you through a "home enema preparation" is as easy as doing a YouTube search. And there’s no shortage of Reddit threads and internet comment sections where people can discuss their use of FMTs to cure a spectrum of ailments. In that respect, Zayner’s just the latest addition to a movement of individuals who — for better or worse — have taken their digestive health into their own hands. "I hear from a shocking number of people who are doing things like this," says Catherine Duff, founder of The Fecal Transplant Foundation, a nonprofit that aims to help FMT patients and raise awareness of the procedure. "Mostly for gastrointestinal things, but also for almost anything you can think of."

Duff doesn’t advocate for DIY transplants, but people still contact her to inquire about them. "My concern is that there are so many desperate people who haven’t found an answer with big pharma, and so they search for a magic bullet," she says. "But generally people don’t seem to have a grasp on what the long-term effects of this could be — because nobody knows."

Zayner cat

A few weeks after his transplant, Zayner traveled to New Orleans to participate in the 2016 Bayer AgVocacy Forum. The last time he attended, four or five years ago, his digestive system didn’t fare well. This time it was different.

In an email he sent entitled "new stomach is a powerhouse," he described a gluttonous diet: chicken fried steak, beignets, and a po’ boy with a crawfish reduction. The conference also involved lots of drinking: over the course of three days, Zayner had beer, shots of Jameson, a frozen hurricane, gin and tonics, and vodka Red Bulls. His stomach "powered through like I was 21," he wrote, ecstatic. He was defecating only once a day. "It’s weird, but so cool," he added. "No matter how much I have changed my diet over the years from mostly vegetarian to mostly meatatarian, it never changed my poop schedule — it gives me hope."

"That is pretty insane," he said in a shaky voice. "The experiment actually worked."

Then, two weeks ago, I received a text message from him. Argonne National Laboratory had completed the sequencing. With the results in hand, Zayner performed a statistical analysis to find out if the bacterial composition of his skin, nose, mouth, and feces had changed over time — and whether the transplant had caused it to resemble Michael’s. Days later, Zayner revealed the results of the analysis to me — and to himself — over Skype.

The connection was poor, but I could tell from Zayner’s pixelated face that he was becoming emotional. The bacterial composition of Zayner’s post-transplant feces were consistently more closely related to Michael’s feces than his own poop prior to the experiment. "That is pretty insane," he said in a shaky voice. "The experiment actually worked."

The skin microbiome transfer results were less impressive. During Zayner’s stay at the hotel, the bacterial composition of the skin on his arms morphed to resemble Michael’s. But that didn’t last long: once he was back home, the arm samples began to resemble samples taken from his girlfriend and his cat. The results for his mouth and nose were all over the place, making it hard to reach any conclusions. The experiment was both a hit and a miss, but for Zayner it was a success. "It’s exciting to think that we have a chance to affect the outcome of our own lives in these medical instances."

To get reliable results, scientific researchers typically follow rigorous protocols: multiple participants, control groups, perfectly controlled conditions. Zayner did none of that. Jason Koval, a microbiologist who does independent sequencing work in Argonne’s labs, replicated Zayner’s analysis, and his results were almost identical to Zayner’s. But because of Zayner’s lack of rigor, he was more skeptical of the experiment’s conclusion. The small number of samples Zayner collected means that it would be almost impossible to tell if the differences he found between various samples are statistically significant. As a result, his experiment is more of an anecdote than science, Koval said. "It’s a fascinating pilot study," but "you can’t firmly say ‘yes, this happened.’"

* *

I Skyped with Zayner in early May. He looked sweaty and tired. Running The ODIN was stressful, he said. But more than two months after the transplant, he was still feeling a lot better — and defecating a lot less. "Probably 95 percent to 99 percent of the time, it’s only once in the morning," he told me.

We also talked about his new living arrangements — he’s moved to a larger home in the East Bay with his brother, his girlfriend, and one of his ODIN employees — and about his recent weight loss. He said he’s lost about 10 pounds which was both good news and a bit concerning.

Before the call ended, we discussed one more piece of anecdotal evidence that the transplant had worked: Zayner’s newfound taste for sweets. Gut bacteria has been shown to influence what a person eats and Michael, Zayner’s friend-turned-stool-donor, has a serious sweet tooth: he can consume an entire a box of Oreos in one sitting. Before the transplant, Zayner was never one for cookies. "Now I crave them," he said. The previous evening, he ate three Oreos before bed. It wasn’t scientific proof, really, but for Zayner it was meaningful.

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This article originally appeared at:

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