Impact of Blueberry Consumption on Gastrointestinal Health

Inclusion Criteria: * obese (BMI +/- 30.0 kg/m2) * shift workers (shift work overnight (third shift) +/= 3 days/week for the past 3 months) * 19-70 years of age Exclusion Criteria: * patient history of gastrointestinal diseases except for hiatal hernia, GERD, or hemorrhoids, mild gastrointestinal symptoms * elevated laboratory values from a comprehensive metabolic panel (CMP) and complete blood count (CBC) with the exception of glucose (+/= 126 mg/dL; if elevated, confirmed with HA1c of greater than or equal to 6.5%) and ALT, AST, or ALP over 2 times normal levels (to allow for mild elevations resulting from fatty liver often seen in obese) unless approved by study physician * currently pregnant or plans to become pregnant during the study as determined by participant report * antibiotic use within the last 12 weeks prior to enrollment * presence of chronic metabolic disease (e.g., cardiovascular disease, diabetes, cancer) or per physician discretion * recent (past 4 weeks) major change in dietary habits or a plan to have a major change in dietary habits during the study * habitual blueberry consumption of more than 0.5 cups 2x/week or a 4-week washout period if consumes * allergy or intolerance to blueberries * consumption of supplemental fiber, probiotics or prebiotics without an appropriate 4-week washout period * restrictive dietary patterns (e.g., ketogenic, Paleolithic) or a diet high in fiber (+/= 14 g/1000 kilocalories) to increase study result generalizability to the U.S. population (low-fiber diet), as well as provide another stimuli for gut leakiness * unwillingness to consent to the study.