Small Bowel Microbiota Characterization in Healthy Individuals Before and After Consumption of a Western Diet

Western diet for 7 days: the meals in this Western diet will be provided by the Clinical Research and Trials Unit (CRTU) after participants meet with the nutrition staff (to discuss food preferences, how to obtain the meals). The meals will reflect a typical Western diet: a low fiber, high sugar diet with weight maintenance calories with \< 10 grams fiber per day, and a typical US macronutrient calorie distribution of 50% carbs, 35% fat and 15% protein, with no alcohol. At least 50% of carbohydrates will be provided as simple sugars.