Leaky gut syndrome is a proposed condition where the intestinal lining becomes permeable, allowing bacteria and toxins to enter the bloodstream. However, it is not a medically recognized condition, and claims for its existence come mostly from nutritionists and practitioners of alternative medicine. The scientific phenomenon of increased intestinal permeability, also known as "leaky gut," is a real condition that can occur in people with certain chronic gastrointestinal diseases. Some studies suggest that leaky gut may be associated with other autoimmune diseases, chronic fatigue syndrome, fibromyalgia, arthritis, allergies, asthma, acne, obesity, and even mental illness. However, there is no conclusive proof to support claims that leaky gut plays a role in any of these conditions.

Symptoms of leaky gut syndrome may include bloating, gas, cramps, food sensitivities, aches, and pains. The causes of leaky gut are not well understood, but diet likely plays a big role. A diet that is low in fiber and high in sugar and saturated fats may initiate the process of gut inflammation. Chronic stress may also be a factor.

There is little evidence to support the hypothesis that leaky gut causes chronic inflammation throughout the body that results in a wide range of conditions. While some treatments are touted for leaky gut syndrome, such as dietary supplements, probiotics, herbal remedies, gluten-free foods, and low-FODMAP, low-sugar, or antifungal diets, there is little evidence that these treatments are effective. If you have symptoms of leaky gut, it is recommended to see a gastroenterologist who is also trained in nutrition.