Notes on “The essential guide to controlling Crohn’s disease, colitis and other IBDs” by John Hunter

The author, a gastroenterologist, provides insights into best practices for patients to achieve remission. He discusses diet, medications, and surgery.

  1. Elemental diets can induce remission in 80–90% of patients with Crohn’s disease. Originally developed for astronauts, this liquid diet is composed of nutrients in their simplest forms: amino acids instead of whole proteins, simple carbohydrates instead of complex sugars, and a single defined lipid source. Because it is almost completely absorbed in the small intestine, particularly in the ileum, it effectively starves the colonic bacteria, reducing their population by up to 50%. After a few weeks to a few months on the elemental diet, most patients achieve remission. They can then transition gradually back to solid foods, introducing one food group at a time to identify which are well tolerated. This systematic reintroduction helps patients maintain long-term remission by personalizing their diet to avoid foods that trigger symptoms. You are your own best doctor approach.
  2. The elemental diet is not effective in patients with intermediate colitis, which sometimes is classified as Crohn’s, or with ulcerative colitis. The proposed explanation is that UC-related bacteria “feed” on the gut mucus, while the Crohn’s bacteria “feed” on food residues; therefore, it is hard to control UC with a “starvation diet” such as the elemental diet. Instead, treating UC may require an ecology-modifying approach, one that introduces substrates or microbes that can compete with and displace disease-associated bacteria.
  3.  The initial trigger for IBD is an infection causing gastroenteritis. Most people recover, but in some, for unknown reasons, chronic disease develops. There is no single species that causes IBD, and the microbiome from patients does not follow the Koch postulates and is insufficient to cause infection. Nevertheless, in combination with the host’s immune system or gut ecology, it can act as an infectious agent contributing to the onset of IBD.
  4. The food itself is not pathogenic, but rather particular bacterial species that live on food residues.
  5. Crohn’s is an immune system attack on bowel bacteria. It can therefore be treated by altering bacterial metabolism or species, or by suppressing the immune system. Antibiotics are not a sustainable long-term solution, although they may provide temporary relief from symptoms. ~30% of bacteria remain after antibiotic treatment. White cells don’t help much because there is no single pathogen. Essentially, the claim is that antibiotics not only kill bacteria but also trigger the immune system to clear them. But in Crohn’s, the second does not happen.
  6. Approximately 90% of Budenosine is destroyed by first-pass metabolism, and only a small portion ends up in the blood, thereby reducing side effects compared to prednisone. It is a corticosteroid, prescribed for Crohn’s in the ileum and ascending colon, where it releases 50%-60% of its activity. That’s evidence that local action can reduce symptoms
  7. 5-ASA is unlikely to be disease-modifying, but taking it for an extended period may have benefits. Need to know how frequently the disease reappears.

It’s a good book to get an overview of IBD. He presents the less-discussed dietary options for CD. It’s from the 2010s and isn’t updated about new medications.