The Cleveland Clinic's Dr. Mark Hyman is one of a growing number of doctors who believe the path to wellness lies in our intestines in something called "gut flora," or "microbiome." More specifically, it's the relationship between the good and bad bacteria there that determine whether we'll be healthy or sick.
"Many of the things floating around in your blood are informational molecules produced by bacteria that control your biology," Dr. Hyman told CBN News. "So that's how the gut microbiome can be linked to everything in terms of what's going on with us and chronic disease from cancer to heart disease to diabetes to dementia to autism to autoimmune disease to depression and much more."
As the Gut Goes, So Goes the Rest of the Body
Scientists at America's top medical institutions are churning out mounds of data on the microbiome. The bottom line: as the gut goes, so goes the rest of the body.
At the Mayo Clinic's microbiome lab in Rochester, Minnesota, scientists examine human feces to find out exactly which bacteria are in a patient's gut, how much of it is there, and which bacteria may be missing.
Microbiome researcher Dr. Purna Kashyap and his team found more than a thousand different species in the intestines of the healthiest people. It's an important discovery because 80% of our immune system resides there.
"All of our guts have different kinds of bacteria and the more different kinds of bacteria we have, the more diverse. And the less different kinds of bacteria we have the less diverse," Dr. Kashyap explained. "And so if you can imagine, the more different kinds of bacteria – that's generally considered to be good for us because they will be able to tackle intruders much better than if you have less different kinds of bacteria."
Healthiest People Have Trillions of Good Bacteria in the Gut
In addition to the variety, the healthiest people also measure high amounts – trillions – of good bacteria and some bad for a total of about three pounds' worth. That's ten times more bacteria than regular cells.
Another Mayo Clinic microbiome researcher, Dr. Heidi Nelson, sees this as a complex and delicate ecosystem that demands balance.
"We think of the microbiome like a garden. You have to weed it, you have to put seeds in it. You have to water it. There's a lot of things you have to do. It's not usually one thing," Dr. Nelson said.
Since bacteria, like all living creatures, eat and expel certain things, Dr. Nelson explained why having too many or too few can lead to disaster.
"If you have a buildup of certain bad nutrients – let's take for example hydrogen sulfide. We know that some bacteria produce hydrogen sulfide and others remove it and use it. But if you have too much hydrogen sulfide that could, in some people, be the cause of the break of DNA that starts the chain reaction of colon cancer from developing," she said.
How an Unbalanced Gut Leads to Obesity
Not enough good bacteria, or too many bad bacteria, can make us sick and overweight.
According to Johns Hopkins gastroenterologist Dr. Gerard Mullin, author of The Gut Balance Revolution, certain bacteria increase ghrelin, the hormone that causes hunger.
"And when the gut microbiome is in a state of disruption, then we actually have a higher appetite and we crave more food when there is an unhealthy microbiome versus when there's a healthy microbiome," Dr. Mullin explained.
Certain bad bacteria can also cause the body to crave particular foods like sugar or bread.
Similarly, gut dysbiosis suppresses leptin, the hormone that tells us to stop eating. And it gets worse.
"The gut microbiome changes the way we metabolize fiber in foods and can make us absorb more calories in foods in an unhealthy gut environment," Dr. Mullin said.
A newly discovered bacteria can possibly determine whether someone is either slim or obese. In fact, research proves thin people carry more diverse gut bacteria than overweight people. Scientists found people in developing countries have more of this bacteria than Americans.
"There's inflammation that occurs when we have an unhealthy balance of gut bacteria," Dr. Mullin said. "It can really lead to injury in the gut a more permeable gut, which some people call 'leaky gut.' And when that inflammation becomes more systemic, we get insulin resistance and we accumulate fat more readily."
Proof that Gut Bacteria Dictates Health and Weight More than DNA
In a landmark development, researchers at Washington University in St. Louis studied the gut mircobiomes from human twins. While they had identical DNA, one was obese and the other thin. Scientists took bacteria from each twin and put it into germ-free mice. The animals with the obese twin's microbiome also became obese, while the other mice became thinner. Researchers noted the thin human and mice carried more diverse bacteria than their healthier counterparts.
"There's a lot of associations with the microbiome in children and the increased incidence of obesity and metabolic syndrome amongst the pediatric population," said Dr. Gail Cresci, a microbiome researcher at Cleveland Clinic.
Childhood obesity, weight problems among adults and various illnesses from diabetes to Alzheimer's are all tied to not having enough good bacteria in our intestines.
Discover the amazing role your gut health has in regulating your overall health and wellness by clicking on this link to get your free booklet, Build a Better Gut.
*Originally published July 30, 2018.