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Everyone Has a ‘Leaky Gut’
The disease du jour has become a catchall for all kinds of health problems. But is a ‘leaky gut’ really that bad?

There are oodles of #leakygut posts on Twitter, Instagram, and Facebook, many involving graphics and videos that purport to explain how it works and promise ways to heal it. But before you trust your gut to social media, know this: You definitely have a leaky gut. Everyone does. In fact, intestinal permeability, as it’s known medically, is normal. Until it’s not. If too much stuff passes from the digestive system into the blood, or if the wrong things get through, like harmful bacteria, infections and diseases may ensue — at least in theory.
But hyperpermeability — the scientific term for “leaky gut syndrome”—has not yet been proven to cause any human diseases. Rather, this supposed disease du jour is but one actor with a role in a multi-act interplay of body systems related to numerous chronic human ills. Among the conditions possibly related to leaky gut, according to several studies and interviews with multiple researchers: obesity, diabetes, heart failure, irritable bowel syndrome, multiple sclerosis, autism, celiac disease, cancer, and Crohn’s, Parkinson’s, and Alzheimer’s disease.
Some proponents of leaky gut syndrome say, without solid evidence, that it causes a range of other problems, from gas, bloating, and cramps to joint pain, moodiness, and poor sleep.
“Leaky gut is a syndrome that may be associated with any disease, acute or chronic, that affects intestinal wall function and therefore increases gut-to-blood penetration of microbiota-produced compounds,” says Marcin Ufnal, MD, PhD, who leads the Department of Experimental Physiology and Pathophysiology at the Medical University of Warsaw in Poland.
“Leaky gut syndrome is the belief that a leaky gut is the source of all ailments and diseases.”
But in addition to whatever it might cause, hyperpermeability is also thought to be caused by several common diseases, including high blood pressure, heart disease, and diabetes — three conditions that damage blood vessels and nerves of the intestinal wall — as well as inflammatory bowel disease, Ufnal…