What We Know About Leaky Gut Syndrome
The majority of your inner organs are protected against the elements. But the gastrointestinal tract—or more precisely, the inside of the gastrointestinal tract—comes in contact with items from the outside world every day.
The foods you eat enter the body via the mouth, travel to the stomach, where they’re partially digested, and move on to the intestines, where the real work of extracting the nutrients and energy we need to live and thrive takes place.
The system usually works quite well, but for some folks, it can spring leaks—just as any well-used plumbing system might. This can lead to a serious condition called leaky gut.
“Leaky gut is a great visual term for patients, but it isn’t a true medical diagnosis,” says Dr. John Whyte, a board-certified internist based in the Washington, D.C., area. Rather than being a precise diagnosis, the term “describes the fact that your intestines aren’t working properly.”
Also sometimes referred to as heightened or increased intestinal permeability, leaky gut “is a condition in which the lining of the intestines become inflamed, damaged, or irritated, allowing microbial toxins and undigested food particles to flood into the bloodstream,” says Lacey Dunn, a functional medicine dietitian and author of The Women’s Guide to Hormonal Harmony.
Enterocytes are the weakening connections that connect cells in the intestinal wall. They also become less permeable. This means undigested food particles and the enzymes your body produces to break down and absorb nutrients from food end up outside the gut, where they don’t belong. “Think of your gut lining like your front door. You want the good guys (vitamins and minerals) to come in, but the bad guys (toxins and pathogens) to stay out,” Dunn says. “This is the same with your intestinal tract.”
Dr. Dawn Beaulieu, who is director of Vanderbilt Inflammatory Bold Disease Clinic’s functional medicine IBD program in Nashville. These slough off, and they are replaced approximately every 4-7 days. “This constant turnover presents an opportunity for ‘holes’ to form in the barrier,” says Beaulieu, who’s also a GI educator at the Institute for Functional Medicine. “The intestinal barrier is not impenetrable, and it shouldn’t be.” But it’s a Goldilocks proposition: some permeability is required for the body to function, but too much can lead to problems.
Leakage of material from the stomach into the bloodstream may lead to infections, widespread inflammation and even increased risk for certain autoimmune diseases. It can also have serious implications for nutrition. “It’s a double whammy, since you aren’t absorbing important vitamins and nutrients, and harmful substances that pass through are disrupting your hormones and immune system,” Whyte explains.
Symptoms often include bloating, nausea, and cramping, but “because the gut impacts our entire body, it can also cause headaches, rashes, fatigue, and joint pain,” Whyte says.
Dunn states that an increase in intestinalpermeability can cause a variety of symptoms including depression and anxiety, as well as chronic fatigue, headaches, migraines, joint pain, asthma, mood disorders, ADHD, and arthritis. In some cases, “leaky gut can manifest without gut-related symptoms,” she notes. “In many cases in my clinical practice, I’ve seen individuals with just skin issues or anxiety have gut infections such as parasites alongside a leaky gut.”
According to Dr. Anil Sing, Orlando Health’s gastroenterologist, it can be difficult for doctors to pinpoint the cause of the issue due too many symptoms. “There’s no one particular symptom” that defines leaky gut: “Some will have diarrhea or constipation, abdominal bloating, or they could feel tired. Sometimes they have nutritional deficiencies.”
These symptoms can overlap with other GI disorders and conditions. “You have to rule out other conditions like celiac disease, irritable bowel, or colitis” before a diagnosis of leaky gut is made, Singh says.
Unfortunately, while the barrier function of the intestinal lining has been studied extensively, this hasn’t yet translated into a precise way to diagnose leaky gut. “Even after decades of scientific investigation, we currently do not have an accurate test for diagnosis,” says Dr. Kaunteya Reddy, medical director of the department of gastroenterology at the Redlands Community Hospital in Redlands, Calif.
One noninvasive test that’s sometimes used measures the ratio of lactulose to mannitol—a marker of mucosal intestinal function—but Singh says it isn’t widely available. It is possible to test for nutritional deficiencies, regardless of whether they are due to leaky gut syndrome or any other condition.
Leaky gut: Who is it?
Anyone can develop increased intestinal permeability, though “there are some people whose genetics may predispose them to a more sensitive digestive tract,” Beaulieu says. People with IBD, gluten sensitivity or celiac disease may have a higher chance of developing increased intestinal permeability. However, “genetics isn’t the main factor,” Beaulieu says. “The food that we eat and how we live in the world around us is likely the main driver for our intestinal-barrier dysfunction.”
American eating habits are high in processed food, saturated fat, and sugar. They also have low fiber. Increasingly, studies are showing that this type of eating “is a big driver in our impaired intestinal function,” Beaulieu says. Poor sleep and excessive alcohol intake can also affect the delicate structure of the gut.
Reddy notes that use of nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen sodium, are “known to cause damage to the intestinal lining and implicated in causing a leaky gut.” Minimizing the use of NSAIDs may help heal the leaky barrier.
People who already have a health issue related to the gastrointestinal tract, such as irritable bowel symptoms, Crohn’s disease, or colitis, are more likely to develop leaky gut, Singh says. Other risk factors include autoimmune disorders, arthritis, lupus, and Hashimoto’s disease, which is an autoimmune disease that affects the thyroid gland and the metabolism-regulating hormones it produces.
Exactly why this happens isn’t completely understood, but Singh says the normal bacteria that reside in the gut and help support a healthy immune system, proper digestion, and a range of other bodily functions tend to get replaced or lost, which causes inflammation. “Inflammation leads to symptoms or signs of leaky gut syndrome, because where there’s inflammation, that will cause increased permeability,” he says.
Considerations for your health
While an autoimmune disorder like Crohn’s disease can elevate your risk of developing leaky gut syndrome, it appears the risk goes both ways: having increased intestinal permeability has been linked with an increased risk of developing several other conditions, such as arthritis, lupus, and diabetes. This connection is still being confirmed by more research.
Additionally, other health conditions such as leaky gut or infection can be caused by a leaky stomach. Candida (yeast infections); H. pyloriDunn states that this is a form of bacteria which can cause stomachaches and nausea and other GI symptoms.
You could be at risk for nutritional deficiencies if your gut is leaky. For example, if your body isn’t absorbing enough iodine, you could develop hypothyroidism. Low vitamin B12 levels can cause heart palpitations.
Leaky gut Syndrome: How to deal
If your doctor suspects leaky gut syndrome, or if you’re at risk of developing it, you’ll likely be advised to make a number of lifestyle changes to help alleviate symptoms and better manage the ailment. “There is no medication that we can use,” Singh says. “It’s basically lifestyle changes,” such as changing your diet and avoiding stress.
Working with a functional-medicine specialist can be helpful for some patients. “The concept of functional medicine is to create balance within our bodily systems, and this all begins in the gut,” Beaulieu says. A functional medicine practitioner will typically “follow a 5R framework for gut restoration,” which includes five steps:
Remove the things that are negatively affecting the GI tract, such as medications that might be damaging the intestines, foods you’re allergic to, toxins, and stressors. You can no longer eat processed food or excessive sugar.
You can replace these items with healthier, more digestible foods. Dunn recommends a plant-based high-fiber diet. “Diversity of plants in your diet is one of the biggest contributors to a healthy gut. Fiber is your friend.”
Re-inculcate the gut with probiotics, prebiotics, and/or postbiotic foods that encourage beneficial bacteria to flourish. Fermented foods like sauerkraut and kimchi can be beneficial for the microbiome of your gut.
Supplements and foods can repair damaged intestinal lining. Beaulieu recommends “eating the rainbow of foods.” Vitamin and mineral supplements such as vitamin D, omega-3 fatty acids, L-glutamine, and aloe can help support the body’s efforts to repair the gut lining.
Balance your lifestyle to promote better health. “Sleep, exercise, and stress all affect the GI tract,” Beaulieu says. “Balancing all of these is crucial for gut health.” While staying physically active is a good idea for overall health, Beaulieu notes that endurance exercise, such as running, biking, or boxing, can increase the risk of leaky gut, because excessive, intense exercise is a “stress-induced state” that can alter barrier function in the gut. Stay active, but don’t overdo it.
Beaulieu says that some doctors recommend adding probiotics to their diets. However, there is limited evidence and research done only on animals. We need more research and data.
Dunn suggests that keeping hydrated is an important way to improve gut health and wellness. “Every day, drink a minimum of half your body weight in ounces of water.” But stay away from alcoholic drinks; the sugars in alcohol can exacerbate symptoms of leaky gut.
Beaulieu notes that in some mainstream medicine circles, “the concept of leaky gut is controversial,” in part because “there’s no gold standard that everyone agrees upon that can test for this, and there’s no documented scientific evidence that these changes in intestinal mucosal function will always result in metabolic changes.”
Still, “the data are compelling, and we are learning more every day,” Beaulieu says. There’s no reason not to eat right and reduce your stress levels—and if you suspect you might have leaky gut, connect with a provider who can help you manage it.