Location: Sugarbeet and Potato Research
Project Number: 3060-21650-001-016-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 1, 2019
End Date: Feb 28, 2023
Objectives for the life of the project will be to: (1) Characterize indices of systemic inflammation and gut microbiota composition and function after chronic (12 weeks) intake of pulses compared to control diet in human OW/OW-IR (over weight/obese – insulin resistant) participants; and (2) Characterize dietary- and microbial-derived metabolite pools after regular intake of pulses (12 weeks) in human OW/OB-IR participants compared to control diet.
The study is a randomized, 3-arm, parallel, placebo-controlled design. Human participants (n=66 completers) with Body Mass Index >25 and fasting glucose concentration between 100 mg/dL and 125 mg/dL (Pre-Diabetes) will be recruited. Recruited subjects must meet all eligibility criteria, sign and date a written Institutional Review Board (IRB)-approved Informed Consent Form. Participants will be randomized into one of the three study food intervention groups. Following 1-week diet stabilization and washout (based on our previous studies) from diets that interfere with the study outcome (such as high polyphenolic diet), subjects will undergo an oral glucose tolerance test (OGTT) to assess insulin resistance at baseline. Blood, urine, and fecal samples will be obtained prior to OGTT (i.e., baseline samples). Participants will then begin the chronic feeding protocol and will ingest the study foods daily for 12 weeks (black beans; chickpeas; or white rice (control) - 1 cooked cup/day). The polyphenolic composition of pulses in cans will be analyzed to determine the best study treatment. Study foods will be provided at weekly visits. Mid-study (Week 6), OGTT, urine, blood and fecal samples will be collected to monitor modifications occurring in the metabolites and gut microbiome during the supplementation. After the 12 weeks of daily intake, another OGTT protocol will be repeated and a 3rd fecal/urine and baseline blood samples will be collected to determine insulin resistance, the gut microbial composition, and final status of metabolites in response to the supplementation.