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Leaky Gut Syndrome: What Is It?

What you should know if you think you have leaky gut syndrome.
WebMD Feature

"Leaky gut syndrome" is said to have symptoms including bloating, gas, cramps, food sensitivities, and aches and pains. But it's something of a medical mystery.

“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.”

Intestinal Permeability

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.

Little is known about other causes of leaky gut that aren't linked to certain types of drugs, radiation therapy, or food allergies.

Unsolved Mystery

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.

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