Acute Berry Intake on Metabolic Control and Cognitive Function
Condition: Healthy
Study type: Interventional

Summary: 
      The objectives of this study are:

        1. Evaluate the effects of acute dietary raspberry intake on metabolic-associated
           impairments in cognitive and psychomotor function in overweight/obese adults (55-70y)
           following a meal challenge

        2. Evaluate the effects of acute dietary raspberry on measures of vascular function.
    

Detailed description: 
      The proposed study will be conducted in humans according to Good Clinical Practice (GCP)
      guidelines. All subjects will review and sign an Informed Consent Form approved by the
      Illinois Institute of Technology's Institutional Review Boards (IRB) prior to screening.

      This multi-center clinical trial is a randomized, single-blind, 2-arm, placebo-controlled,
      within subject cross-over trial, featuring a repeated postprandial sampling paradigm to
      evaluate the effects of acute dietary red raspberry intake on cognitive function,
      inflammation, insulin sensitivity / glucose handling and vascular function in
      overweight/obese older adults after consuming a standardized challenge meal.

      A planned sample size of 30 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 provide subject with their site-specific, IRB-approved
      informed consent document prior to the start of any study related procedures. Subject
      eligibility will be determined through anthropometric measurements, vital signs, fasting
      blood glucose test (finger prick), and completion of a survey relate to general eating,
      health, mood and exercise habits.

      Eligible subjects will follow a limited polyphenolic diet throughout the duration of their
      participation, although stricter guidelines will be imposed during the 3 days prior to a
      study visit. Shopping lists and meal plans will be provided to subjects, along with
      counseling by the investigator's study dietitians, to help subjects adhere to the limited
      polyphenolic diet. The trial will initiate with a 3-day food diary to assess background
      (pre-study) dietary intake followed by counseling to follow a diet relatively low in
      (poly)phenolic rich-beverages/foods, which will be maintained for the duration of the
      experiment. After an initial 7 day run-in period on the limited polyphenolic diet, subjects
      will be randomized to 1 of 2 treatment sequences. Treatment codes will be maintained by the
      principal investigator/study physician. All subjects will receive both treatments, once each
      on 2 different occasions and separated by at least 1 week. Red raspberries or placebo will be
      provided with a standardized meal providing 840 kcal. A low-polyphenol snack will be provided
      to subjects after their final cognitive assessment.

      Each visit will last ~ 9.5 hours and subjects will be required to remain at the Clinical Unit
      for the duration of the visit. Blood samples will be collected at 0 (fasting) and at 0.5 h, 1
      h, 2 h, 4 h, 5 h, 6 h and 7.5 h via a catheter placed on the non-dominant arm by a registered
      nurse. Cognitive function will be measured at 0 (fasting), 2 h, and 6 h. FMD or NIRS will be
      conducted at the CNRC or the HNRCA, respectively at 0 (fasting), and at 1 h and 5 h.
    

Intervention name(s): Active breakfast; Control breakfast
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): freeze-dried red raspberry powder (12.5 g) in drink+ freeze-dried red raspberry powder (12.5 g) in buttermilk biscuit sandwich; Control drink + buttermilk biscuit sandwich
Allocation: Randomized
Intervention model: Crossover Assignment
Intervention model description: Multi center, randomized, single-blind, 2-arm, placebo-controlled, within subject cross-over trial, featuring a repeated postprandial sampling paradigm
Masking: Single (Participant)
Primary purpose: Other
Keywords: Raspberry; Metabolic responses; Endothelial function; Cognitive function