Toddler holding toilet lid
At Every Turn > Primary Care > The straight poop: How bugs in your bowel affect your health
News Feb 06, 2015

The straight poop: How bugs in your bowel affect your health

B Li, MD, Gastroenterologist Feb 06, 2015

“Poop,” my 2-year-old granddaughter says enthusiastically. “Me. Look … Woooow!”

She’s acquired the curiosity bug and wants to view the poop before it’s flushed away. She’s clearly on to something, because that poop is a significant indicator of her health.

Wait, what?

I am talking about the intestinal microbiome (the entire colony of bacteria that resides in our bowel) and the intestinal microbiota (the specific bacteria that live in the colony).

We used to consider bacteria in the bowel as purely discarded waste and the source of contamination and serious infections. But over the past two decades we have come to view them in an entirely fresh light.

Here are some fun facts about the bacteria that live in our intestine, mouth and skin:

  • 100 billion bacteria live in stool the size of one’s pinkie
  • The entire colony of bacteria weighs about 3 pounds, nearly the size of your brain
  • We have 10 times more bacterial cells than we do human (eukaryotic) cells

The colony of bacteria affects our health in two main ways:

  • Our immunity by influencing the development of inflammatory bowel disease, food allergies, and even celiac disease
  • Our metabolism by influencing the development of obesity and diabetes

Linking obesity to bacteria

How is excess weight gain linked to bacteria? We’ve known that they help keep us well hydrated by fermenting sugars to short-chain fatty acids that help absorb water from the colon. When your child takes antibiotics like Augmentin, you reduce this fermentation and water absorption, and may develop diarrhea. In obese individuals, the microbiota profile is altered to work at high efficiency to absorb extra calories from carbs.

In one clever study, the colonic bacteria from human twins — one obese and one not — was injected into sterile mice. Those receiving the obese bacteria gained weight faster than those given the slim microbiota. This excess weight gain could be reversed by using the “slim bacteria” or by a vegetarian-type diet. So, mouse obesity may be transferred (and reversed) through those little bugs in the bowel!

The role of bacterial diversity

How do we acquire our own intestinal microbiota? It begins when we become fully colonized by bacteria within 24 hours of being born. Birthing profoundly affects the microbiota, as those born by cesarean section have different and less diverse microbiota than those born vaginally. This appears to increase the subsequent risk of developing food allergies and inflammatory bowel disease (IBD), Crohn’s disease or ulcerative colitis later on.

Although the microbiota largely become set by the time we’re toddlers, other factors influence its composition. Diet is a major one, especially poorly digestible sugars and fibers. Repeated courses of antibiotics in toddlers reduce the bacterial diversity and raise the risk of developing IBD. Finally, probiotics (beneficial bacteria) can alter the microbiota as long as they are taken, but in most disorders we don’t know exactly which bacteria, the exact dose, how long to treat, or whether they should be used in combination.

I could wax probiotically on and on but I’ll save that topic for another blog post.

The power of poop transplants

Dangerous infections like Clostridia difficile (C. diff) illustrates the potential power of the intestinal microbiota. This bug can colonize (live without causing symptoms or disease) the colon, but under conditions of prolonged pest control (antibiotic), the flowers (good bacteria) are destroyed, and the weeds (C. diff) overgrow, causing fever and bloody diarrhea from serious colonic inflammation. This infection can resist our best antibiotics.

In an exciting recent development, fecal matter transfer (FMT) aka poop transplant from a healthy donor (usually a family member or volunteer at a fecal bank in Boston where deposits are deposits) can eradicate resistant infections in 90 percent. This therapy is usually administered through a colonoscope while the child is asleep. This odiferous approach is likely to be used to treat other conditions as well.

Steve Werlin, MD, in our gastroenterology group has been our local FMT champion here at Children’s Wisconsin and has cleared institutional concerns and followed the latest national guidelines to ensure that family donors are safe. We performed the first one together, and are now up to seven, all successful, in eradicating C. diff.

Can you imagine wearing a bold sticker proclaiming “I donated poop today!”

What is the bottom line?

Joking aside, bugs in the bowel are a vital key to our overall health.

This area is so important that the National Institutes of Health has funded a national Human Microbiome Project. Nita Salzman, MD, Ph.D., in our group is a leader in the basic science research for that project. It appears that a more diverse population of bacteria of better microbiota could protect us from developing a slew of common chronic disorders.

We are just scratching the surface of a very complex area, but will eventually know how to treat or “untreat” (with fewer or more selective antibiotics) the intestinal microbiome.

Prepare your noses and get used to it. Poop transplants are here to stay.

As for my granddaughter who started this, if she doesn’t outgrow her toddler fixation in a few years, maybe she’ll become a gastroenterologist like Grandpa.

B Li, MD B Li, MD Gastroenterologist Children’s Wisconsin
Children’s Wisconsin has more than 20 primary care offices conveniently located throughout the Milwaukee area and southeast Wisconsin. Find a pediatrician near you. View more articles from B Li, MD

Related stories

Pile of newspapers
News Dec 04, 2024

Children’s Wisconsin and UW Health Kids enter new joint venture

Children’s Wisconsin and UW Health Kids are announcing a new joint venture for shared pediatric cardiac and adult congenital heart care services.

New Children's Wisconsin Appleton Clinic opened March 6
News Oct 25, 2024

Children’s Wisconsin plans pediatric urgent care in Appleton

Urgent care services for kids of all ages will be available seven days a week at the clinic.

At Every Turn new trusted parenting resource from Children's Wisconsin
News Oct 23, 2024

Welcome to At Every Turn

At Every Turn is your new and improved parenting resource from Children's Wisconsin.

Children’s Wisconsin named among the nation’s best by U.S. News & World Report
News Oct 08, 2024

Children’s Wisconsin named among the nation’s best by U.S. News & World Report

Children’s Wisconsin ranked among the best in 8 pediatric specialties.

Children walking through a grassy field with the sun behind them.
News Sep 24, 2024

Children’s Wisconsin announces historic engagement and philanthropy campaign

Brighter Than Ever is the most ambitious and comprehensive engagement and philanthropy campaign in the organization’s history.

MACC Fund Center for Cancer and Blood Disorders at Children's Wisconsin
News Sep 17, 2024

Children's Wisconsin brings life-changing gene therapy to kids with severe sickle cell disease

The MACC Fund Center for Cancer and Blood Disorders is only center in Wisconsin to offer FDA-approved Casgevy therapy to children with severe sickle cell disease or transfusion-dependent thalassemia.

Amy Herbst, VP of Mental and Behavioral Health at Children's Wisconsin, talks with Wisconsin Governor Tony Evers.
News Aug 07, 2024

Milwaukee Journal Sentinel: Children's Wisconsin committed to improving mental health services. It's working.

It's been nearly five years since Children's Wisconsin launched a five-year plan to improve access to behavioral health care for children and adolescents.