 This study aims to determine whether the use of a supplement called xylooligosaccharide XOS increases the number of good bacteria that live in human intestines and can maintain healthy blood sugar levels, and whether XOS has any unpleasant or unexpected side effects when consumed at different dosages. Subjects who participate in this study will be randomized to receive an eight week supply of either a lower dose of XOS or placebo no active substance. This will be determined randomly, in a process similar to flipping a coin. Blood samples will be taken at each visits, including an oral glucose tolerance test. Subjects will also be asked to collect and bring in stool samples at three different time points during the study. 