A group of 1,000 self-reported healthy individuals who had submitted fecal samples (one sample per subject) were selected from the ongoing uBiome citizen science microbiome research study (manuscript in preparation). Of these, 103 extracted fecal samples (see below for more details) did not pass our 10,000 read quality control threshold. We used this stringent threshold to ensure detection of all targeted taxa, even at low abundance. The final cohort therefore included 897 individuals (62% male and 38% female). Participants were explicitly asked about 42 different medical conditions such as cancer, infections, obesity, chronic health issues, and mental health disorders. Selected participants with an average age of 39.7 years (SD = 15.5) responded to an extensive survey and self-reported to be currently and overall in good health. None of the individuals selected for the healthy cohort had ever been diagnosed with high blood sugar, diabetes, gut-related symptoms, or any other medical condition. This study was performed under a Human Subjects Protocol provided by an IRB (E&I Review Services, IRB Study #13044, 05/10/2013). Informed consent was obtained from all participants. Analysis of participant data was performed in aggregate and anonymously.