A Pilot Study to Characterize the Bioavailability and Plasma Profile of Potato Polyphenols in Humans
Condition: Premenopausal Women; Overweight and Obese Women
MeSH terms: Overweight
Study type: Interventional

Summary: 
      Primary objective is to determine the bioavailability of and characterize the kinetic profile
      of target polyphenol metabolites of potatoes over 6 hour postprandial period.

      Secondary objective is to assess the influence of potatoes' bioavailability and kinetic
      profiles on markers of chronic diseases.
    

Detailed description: 
      The proposed study is a single-center, placebo-controlled, randomized, 2-arm, 2-sequence,
      crossover study that characterizes the bioavailability and kinetic profile of potatoes over
      6-hour postprandial day (PPD).

      A planned sample size of 12 will be enrolled into the study. This study will require one
      initial screening visit, pre-study visit, and 2 PPDs. This study will take 3-6 weeks per
      subject to complete.

      The trial will initiate with a screening visit, which will last for about 1-1.5 hours where
      the subjects' height, weight, waist circumference, fasting blood glucose, fasting hs-CRP
      (high sensitivity C-reactive protein) concentration, blood pressure and heart rate will be
      measured and a survey related to general eating, health and exercise habits will be
      completed.

      If willing and eligible to participate, a 3-day food record (2 weekdays and 1 weekend) will
      be given at the screening visit and collected on the following pre-study Visit to assess
      subject's baseline dietary intake and pattern. Also, subjects will be instructed to follow a
      relatively low polyphenolic-diet at least 7 days prior to the first PPD and for the duration
      of the study. Prior to each PPD, a dinner meal will be provided the day before the PPD to
      control the second meal effect from food and beverage intake of the night before the PPD.

      Subjects will arrive at the center in a fasting state for at least 10 hours, well hydrated
      and rested. Each PPD 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 registered nurse will place a catheter in subject's arm for the
      purpose of multiple blood sample collections and take the initial blood draw at fasting. A
      standard high carbohydrate and high fat test meal with either 200g white potato or 200g
      purple potato will be served. Thereafter, timers will be started and blood sample will be
      collected at 20, 40, 60, 120, 180, 240, 300, and 360 minutes for assessment in plasma
      bioavailability and kinetic profile of potato polyphenols and changes in inflammation markers
      and relative metabolic indices. The sequence of receiving the potato treatment at each visit
      will be randomly assigned based on computer generated sequences: white potato-purple potato
      or purple potato-white potato.

      Premenopausal female subjects will be studied during the follicular phase of their menstrual
      cycle because food intake tends to be more stable during the follicular phase (days 1-13)
      than during the luteal phase (days 14-28) when the rise in progesterone levels decrease
      satiety and often resulting in increased intake. Both PPD visits will be placed at least 3
      days apart as well.
    

Intervention name(s): Active Comparator; Placebo Comparator
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): Purple Potato; Placebo Comparator
Other intervention name(s): Purple Potato; White Potato
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Single (Participant)
Primary purpose: Basic Science
Keywords: Purple Potatoes; Polyphenolics