Elemental Diet and Gut Microbiome
Condition: Irritable Bowel Syndrome
MeSH terms: Irritable Bowel Syndrome
Study type: Interventional

Summary: 
      he primary objective of this study is to assess changes in stool microbiome profiles in
      patients after an elemental diet.
    

Detailed description: 
      The gut microbiome is the collection of microbes residing inside the gastrointestinal (GI)
      tract. The involvement of the gut microbiome has been demonstrated in multiple diseases
      processes including irritable bowel syndrome, small intestinal bacterial overgrowth (SIBO),
      Crohn's disease, and ulcerative colitis among many other diseases. A "healthy" diverse gut
      microbiome is associated with a better response to infections and immunopathogenic insults.

      Many factors can affect the gut microbiome including medications, age, disease states and
      diet. Among these factors, diet is the easiest factor that can be modified to improve the gut
      microbiome. However, conducting dietary trials is challenging due to the inability to fully
      standardize what subjects eat even with strict dietary instructions. Moreover, individual
      preferences/allergies, the source of dietary ingredients, freshness, and food preparation are
      important steps which affect the diet and are challenging to standardize among subjects in a
      diet trial. This has led to significant ambiguity regarding the true extent and depth of
      dietary modifications on gut microbiome.

      Apart from vitamins and micronutrients, the three main food macronutrients in the human diet
      are carbohydrates, protein and fat. Upon digestion, carbohydrates are broken into
      monosaccharides, proteins into amino acids and fats mainly into fatty acids. Elemental diets
      contain all daily required vitamins, micronutrients and macronutrients. The ingredients are
      readily digestible (carbohydrates, amino acids and medium chain fatty acids) and are absorbed
      within the proximal small bowel. One main disadvantage of elemental diets such as Vivonex is
      their unpalatability which has limited their use. A palatable elemental diet can be a very
      valuable tool to enable us to assess the effects of diet on the gut microbiome as it bypasses
      several confounding effects in dietary trials such as food allergies, individual digestion
      variability, completeness of the diet ingredients, and food preparation.

      SIBO is a condition in which the gut microbiome plays an integral role and is defined by
      abnormal and excessive numbers of bacteria in the small bowel.4 Interest in SIBO has been
      fueled by the ever-increasing awareness of the human microbiome and its potential
      relationships to human health and disease. SIBO is a preferred condition to assess the
      effects of elemental diet on the gut microbiome, given the known role of the gut microbiome
      in SIBO. Those with SIBO experience a range of intestinal and extraintestinal symptoms
      including diarrhea, nausea, bloating, abdominal pain, and excess gas.

      Commonly, SIBO has been defined by two methods: direct culture of small bowel aspirates, and
      indirect assessment using carbohydrate (e.g. lactulose or glucose) breath testing. SIBO is
      generally treated with antibiotics. Low fermentable and elemental diets also have positive
      effects in SIBO. Based on the potential effects of diet on the gut microbiome, we hypothesize
      that a two-week period of an elemental diet can change the gut microbiome in SIBO subjects.
    

Intervention name(s): Elemental Diet
Intervention type(s): Dietary Supplement
Intervention description(s): . Elemental diets contain all daily required vitamins, micronutrients and macronutrients. The ingredients are readily digestible (carbohydrates, amino acids and medium chain fatty acids) and are absorbed within the proximal small bowel. One main disadvantage of elemental diets such as Vivonex is their unpalatability3 which has limited their use.
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Other