Digest This

peristalsis, the series of muscle contractions — think of toothpaste being squeezed through a tube — essential for swallowing, digestion, for absorption of food and bowel movement. When the enteric nervous system is out of kilter, it can result in conditions including irritable bowel syndrome (someone could repeatedly experience diarrhea as well as constipation) or gastroparesis (the stomach muscles or the nerves that drive them stop working, and food doesn't move out of the stomach the way it should). The gut produces 90 percent of the body's serotonin and half of its dopamine; these are powerful neurotransmitters that affect mood, help the mind stay calm and focused, and are natural antidepressants. The reverse is also true: Changes in our mood can also affect everything in the gut. It is not surprising therefore that in some individuals, certain foods can trigger a complex of symptoms including gastrointestinal discomfort, malaise, fatigue, pain, weakness, and mood alterations including depression. Further, it is quite possible that many individuals are not even aware of such an interaction or can ascertain which particular foods their bodies react adversely too. An example of this interaction that is now widely known by the public is the reaction to gluten. Gluten sensitivity, in the absence of markers of classical celiac disease, is arguably the most common food intolerance identified by patients. It is difficult to diagnose because we do not as yet have reliable tests but often suspected by many patients to be responsible for a variety of symptoms related to their gut, body and mind. It is fair to say that our knowledge of gluten or other food sensitivities/intolerance is a work in progress and many questions still cannot be answered confidently. These include the following: 1.How do specific components of food interact with the gut, separately or together with its epithelial, immune and nerve cells, as well as with the enteric microflora? 2.What are the specific signals resulting from this interaction that are capable of affecting physical and mental health? 3.What are the best tools to identify foods that result in adverse health consequences for individual subjects? 4.How do we use this knowledge to influence individual behavior with respect to their dietary habits? 5.How do we use this knowledge to develop novel and more effective therapies for human health in general? These questions are being answered at the Amos Food, Body & Mind Center at Johns Hopkins where multiple specialties come together- Gastroenterology, Psychiatry/Neuroscience, Microbiology, Immunology and Nutrition science. Patients come here with a variety of problems related to gut motility as well as neurological and auto-immune conditions. They are seen together by our specialists and provided an integrated and compassionate approach to their symptoms. The center is also doing research on the effects of special diets on the gut brain axis and whether this may be related to changes in microbiota. Human Microbiome The full array of microorganisms (the microbiota) that live on and in humans and, more specifically, the collection of microbial genomes that contribute to the broader genetic portrait, or metagenome, of a human. 21 DiGEST THIS

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