“From an MD’s standpoint, it’s a very gray area,” says gastroenterologist Donald Kirby, MD, director of the Center for Human Nutrition at the Cleveland Clinic. “Physicians don’t know enough about the gut, which is our biggest immune system organ.”
"Leaky gut syndrome" isn't a diagnosis taught in medical school. Instead, "leaky gut really means you’ve got a diagnosis that still needs to be made,” Kirby says. “You hope that your doctor is a good-enough Sherlock Holmes, but sometimes it is very hard to make a diagnosis.”
“We don’t know a lot but we know that it exists,” says Linda A. Lee, MD, a gastroenterologist and director of the Johns Hopkins Integrative Medicine and Digestive Center. “In the absence of evidence, we don’t know what it means or what therapies can directly address it.”
A possible cause of leaky gut is increased intestinal permeability or intestinal hyperpermeability.
That could happen when tight junctions in the gut, which control what passes through the lining of the small intestine, don't work properly. That could let substances leak into the bloodstream.
People with celiac disease and Crohn’s disease experience this. “Molecules can get across in some cases, such as Crohn’s, but we don’t know all the causes,” Lee says. Whether hyperpermeability is more of a contributing factor or a consequence is unclear.
But why or how this would happen in someone without those conditions is not clear.
Leaky gut symptoms aren't unique. They're shared by other problems, too. And tests often fail to uncover a definite cause of the problem. That can leave people without a diagnosis and, therefore, untreated.
It’s crucial, Kirby says, to find a doctor who will take time with you and take your concerns seriously.
“You may have leaky gut and we may be able to treat what causes it,” Kirby says. “If you have something going on, it is incumbent upon the medical community to listen to you.”
Unfortunately, Lee says, not all doctors make the effort to get at the root of the problem, and that’s what frequently sends patients to alternative practitioners.
“Often, the reason they have resorted to alternative medicine is because of what they have been told and how they have been treated by other practitioners,” Lee says. “We need to listen.”
Treatment Without Research
In her clinic, Lee combines conventional medicine with evidenced-based complementary therapies. But with leaky gut, she says, the evidence -- about what causes it and how to treat it -- has yet to fully accumulate. This is something that is essential for patients to understand.
“We are in the infancy of understanding what to do,” Lee says. “People who are making claims about what to do are doing so without evidence.”
For example, many web sites offering information on leaky gut, recommend taking L-glutamine supplements to strengthen the lining of the small intestine. Lee says that, theoretically, that makes sense, given glutamine’s role in intestinal function -- but there is no research to back up such claims.
“There’s no evidence that if I give you a pile of glutamine pills, that you will improve,” Lee says.
Lifestyle May Matter
Treating the underlying condition, such as Crohn’s or celiac disease, will often resolve symptoms associated with the condition. But without a firm diagnosis, a doctor's hands are often tied by a lack of evidence.
Diet likely plays a big role in having a leaky gut, Lee and Kirby agree. So if you have symptoms of leaky gut, you would do well to see a gastroenterologist who is also trained in nutrition.
Lee says that lifestyle modifications, such as those that reduce stress and improve the diet, may be among the best ways to treat leaky gut, particularly when no underlying condition is identified. “Chronic health problems are so often due to lifestyle, and we don’t have pills for those,” she says. “We’re talking about the way we live and the way we eat.”