Hold the Prozac and pass the poop pills? Fecal transplant studies dig deep

A Calgary psychiatry professor and department head is leading one of two Canadian studies looking at potential benefits of, well, No. 2.

"You have more serotonin receptors in your gastrointestinal system than in your brain," Dr. Valerie Taylor told The Homestretch.

"We have assumed it's a brain illness because that's where we think emotion is regulated, but it may be much more complicated than that."

Two studies, one in Toronto and one in Calgary, are taking different approaches to the question, 'Can someone else's poo in your system improve your mental health?'

Recruitment is starting for the Calgary study and is halfway done for the Toronto research.

Toronto's study is about ingesting the brown stuff via colonoscopies, whereas Calgary is about pill popping.

"The stool is processed, packaged and put in a capsule form and ingested," Taylor said.

Both studies are randomized, controlled trials, meaning there are placebos and active treatment but some people will get their own poo.

"No one knows who gets what until the end of the study," she said.

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The basis of the study is animal research. Researchers found that giving mice poo from depressed people, in effect, transferred those symptoms to the mouse. Ditto with poop from people with anxiety and autism.

"It is starting to illustrate there is some causality. You can transfer some of these illnesses, so we are hoping you can also transfer wellness," Taylor said.

So the hunt for premium poo starts.

"This is scientific. At the university, we make sure everything is rigorously screened. I don't qualify for three different reasons. I am just not healthy enough," she said.

"We start with the minimum blood donation criteria and add about 10 extra pages of screening to make sure individuals are extraordinarily healthy."

The U.S. Food and Drug Administration halted clinical trials this summer until after two patients developed severe infections from transplants with drug-resistant bacteria, The New York Times reported in June. One patient died.

And Taylor cautions: no Amazon shortcuts, please.

"You can order these pills on the internet. Don't do that," she said.

Researchers at Queen's University launched a trial earlier this year, giving people with depression powdered probiotic bacteria to see if changing the gut bacteria would improve their symptoms.

"One of the main mechanisms that we're going to be studying is how the immune system might be mediating the communication between the brain and the gastrointestinal tract," Caroline Wallace, who is running the trial, told CBC News in February.

The goal of both the Toronto and Calgary studies is to look at the relationship between how good bacteria from one person, when added to the gastrointestinal (GI) system of a second person, impacts the mood of person No. 2.

"A lot of these bacteria directly produce many of the same chemicals, called neurotransmitters, that we try to impact with medication like serotonin, dopamine and gamma aminobutyric acid (GABA). These seem to be deficient in people with depression, anxiety disorders and other mental illnesses," Taylor said.

The researchers hope to clarify what's going on.

"If the science does not back this up, it's important to tell people and we need to look elsewhere for answers," Taylor said.

"We are not interested in promoting something that doesn't work. Either way, this is going to be helpful."