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WHNRC Fiber Intervention Study
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Who is conducting the study?

Danielle Lemay, Ph.D. from the Western Human Nutrition Research Center (WHNRC) and Department of Nutrition, at the University of California, Davis.

What is the purpose of this study?

We hope to determine if adding inulin, a type of dietary fiber, to a diet that does not have enough fiber would raise the levels of potentially beneficial bacteria in the gut, reduce gut inflammation and gut leakiness caused by a vaccine, and increase immune response to vaccination

Where is the study being conducted?

WHNRC, 430 West Health Sciences Drive, University of California, Davis, California, 95616

Who can participate in this study?

Adults between the ages of 18 - 59 who are normal weight or overweight. Must be willing to consume inulin or maltodextrin and an oral travel vaccine, provide fasting blood draws and collect urine and stool samples. Must be willing to visit WHNRC multiple times over the course of 9 weeks.

What would exclude me from participating in the study?

  1. You are pregnant, breastfeeding or planning to become pregnant during the duration of the study.
  2. You are allergic to the oral typhoid fever vaccine or vaccine components.
  3. You are taking anti-inflammatory medications.
  4. You have HIV/AIDS or another disease the affects the immune system

What can I expect to happen during the study?

First, you will be screened for eligibility using an online survey (Qualtrics Research Suite, a UC Davis Cloud Service).

Second, if you meet our basic inclusion criteria you will come to the WHNRC for a screening visit so we can fully explain the study to you, get your consent to participate, and conduct a more in-depth assessment of your eligibility. This assessment will include measurement of body weight, height, body temperature, blood pressure, and the assessment of veins for blood draws. Blood will be drawn by a licensed phlebotomist. This visit will last about 45 - 60 minutes. A follow-up screening visit in-person or via Skype, Zoom, or phone call with a physician will be scheduled to determine medical eligibility to be included in the study.

After completing these pre-study visits, we will schedule you for the fiber intervention study. This study will last 66 days. In this time, you will visit the WHNRC 9 times.

You will be asked to pick up a stool collection shipper, stool diary, cooler with supplies and instructions from the WHNRC on specified days. The shipper will be stored at home during the collection week, and you will return it at the end of each collection period (Day 8, 26, 37, 44, 66). There will be a total of 10 stool samples collected.

You will also be asked to schedule a medication pickup at the UC Davis Medical Center, Pavilion Pharmacy, to pick up your prescription lactulose and vaccine. You will store these at home throughout the study.

Because this is a randomized controlled trial, you will be given either inulin or maltodextrin (control) in plastic bottles. Each bottle will contain 12 grams of one of the two fibers. You will dissolve the contents of the bottles in water daily with your evening meal from Day 9 to Day 43.

On Day 8 and Day 26 of the study, we will ask female subjects to take a urine pregnancy test and all subjects to give blood for an HIV AB/AG combo screen blood test. We are testing you for HIV because anyone with HIV or AIDS should NOT take the oral, live typhoid fever vaccine.

A registered nurse will counsel subjects on how to take the lactulose (Day 8) and Vivotif vaccine (Day 30) and discuss potential side effects.

You will be contacted by a dietary recall technician from the University of Minnesota Nutrition Coordinating Center (NCC) at various time points throughout the study. They will collect information on the food you ate the previous day on a total of 9 separate days.

On Day 8, 26, and 37, we will measure your gut permeability after the consumption of a 2-sugar drink (consisting of lactulose and D-mannitol), and blood and urine samples will be taken.

On day 30, 32, 34 and 36, one oral typhoid vaccine capsule will be self-administered one-hour before an evening meal.

What is your compensation from this study?

If you fully complete the study, the total compensation is $560.  If you complete only a portion of the study, you will be compensated only for those portions completed.

What should I do if I have questions or want to participate in the study?

Please contact our study line at 530-752-5177, press #2, and leave a message that you are interested in the WHNRC Fiber Intervention study. One of our study team members will contact you to let you know more about the study and answer questions.

Studypages - WHNRC Fiber Intervention Study