Postprandial Glycemia in Orange Products
Condition: Healthy
Study type: Interventional

Summary: 
      The primary objective of the study is to compare the effects of a whole orange, orange juice
      alone, and orange juice with pomace on 2 hr glycemic response as measured by maximal glucose
      concentration.
    

Detailed description: 
      This study is a randomized, 3-arm, within subject cross-over trial allowing for three acute
      evaluations of 100% orange juice (250 g), 100% Orange Juice with enzyme-treated orange pomace
      fiber (157 g orange juice with 100 g orange pomace), and raw orange (227 g edible portion of
      navel orange) on glucose and insulin response in fifty-two healthy men and women aged 20-45
      years.

      A planned sample size of 52 will be enrolled into the study. This study will require one
      initial screening visit and 3 study visits. This study will take approximately 3-4 weeks per
      subject to complete.

      The initial screening visit will take ~2 hours and provide subject with the informed consent
      document and determine subject eligibility through anthropometric measurements, body
      composition measurement, vital signs, fasting blood glucose test (finger prick), a vein
      access scale evaluation, online 24-hr diet recall, and completion of a survey relate to
      general eating, health, and exercise habits. For women, a pregnancy test will be conducted.

      If willing and eligible to participate, subjects will be invited to participate in the study
      for 3 study days. Eligible subjects will be instructed to follow a relatively low
      polyphenolic diet for at least 1 week prior the beginning of the study and continue for the
      duration of the study.

      Each Study Day visit will last about ~3 hours. The day before each of the 3 Study Day visits,
      subjects will be asked to consume the same dinner meal and record on a food record. At each
      Study Day visit, subjects will arrive at the clinic after fasting for 10 to 12 hours and in a
      well-hydrated and well-rested state.

      Each study visit will require blood draws throughout the visit. After evaluation of subject's
      health status (via anthropometric, vital sign and blood glucose measurements and in-person
      interview), a Licensed health Care Professional will place a catheter in subject's arm for
      the purpose of multiple blood sample collections and take the initial blood draw in the
      fasting state. Subjects will be randomized to receive one of study products based on
      randomized treatment sequences for 3 study visits immediately after fasting blood draw.

      Participants will come to the research site on 3 separate occasions separated by a washout
      period. On each occasion 2 fasting blood samples will be obtained at 5 min intervals (-5, 0
      minute (min)). Subjects will then consume one of the 3 treatments. Further blood samples will
      be taken at 15, 25, 30, 35, 40, 45, 60, 75, 90, 105 and 120 min. Self-reported visual analog
      scales (VAS) will be used to measure subject hunger, fullness, desire to eat, and prospective
      food intake. After completion of all study procedures and data/sample collection for the day,
      the catheter will be removed and subjects will be evaluated for safety and/or
      discomfort/symptoms before leaving the study site. They will be given a take-home snack and
      given written instructions in preparation for the next visit. Study day visits will be
      scheduled at least 3 days apart but no more than 7 days.
    

Intervention name(s): Orange Juice1; Orange Juice2; Raw Orange
Intervention type(s): Dietary Supplement; Dietary Supplement; Dietary Supplement
Intervention description(s): 100% Orange Juice; 100% Orange Juice with enzyme-treated orange pomace fiber; Raw Orange
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Single (Participant)
Primary purpose: Basic Science
Keywords: orange pomace fiber; glycemic response; Orange