Pertinent to a recent discussion in the Q&A, I've found more information on leaky gut from a patient, Jesse Thomson, who describes his remission from the autoimmune disease ankylosing spondylitis in an ebook, Reversing Autoimmune Disease: A Personal Success Story.This book is available on Amazon.

Only in his 20s now, Thomson describes a lifelong love of sweets and an aversion to healthy foods.  Although ankyosing spondylitis has a strong genetic component (HLA B27), Thomson feels poor nutrition contributed to the emergence of rheumatic symptoms when he was only 11 years old. As he grew older, he began to study nutrition to see what factors may have contributed to his condition. He learned how a lack of digestive enzymes that are produced in the stomach lining, an organ rich in immune system cells, starts the process. He found that overtaxing the enzymes with increased carbohydrates causes diminished enzymes. Over time this impedes digestion and injures the intestinal lining. Consequently, the lining loses its ability to prevent foreign particles from entering the bloodstream.  In this highly inflammatory process, the intestinal lining becomes more permeable, allowing the entry of foreign antigens into the bloodstream. Reactions to these antigens are thought to precipitate autoimmune disease.

Thomson supports this theory by describing his nutritional support program that brought him into remission. Following a primarily Paleo diet, Thomson also uses digestive enzymes and a holistic protocol that includes exercise.  Although I didn't see it specifically mentioned and may have missed it, probiotic supplements are also essential for recovery in leaky gut syndrome.

I've heard from several patients over the years who achieved remission after adding probiotic supplements.