The Effects of Protein Source on Appetite Control, Satiety, and Subsequent Food Intake: A Clinical Screening Study
Condition: Appetitive Behavior
Study type: Interventional

Summary: 
      Primary Objective: To examine whether the consumption of preloads varying in protein quality
      effect subsequent meal energy and macronutrient content

      Secondary Objectives: To examine whether the consumption of preloads varying in protein
      quality effect postprandial feelings of hunger, fullness, desire to eat, prospective food
      consumption, and eating initiation.

      Exploratory Objective: To examine whether the consumption of preloads varying in protein
      quality effect postprandial cognitive performance.
    

Detailed description: 
      The investigators propose the following acute, randomized crossover study to compare 5,
      isocaloric yogurt-based preloads containing 20, 30, or 40 g pea protein; 20 g whey protein;
      and an isocaloric carbohydrate (control).

      For 3 consecutive days/pattern, the participants will consume the respective treatment, at
      home, between 7-9 am, based on their habitual breakfast time. (These days are implemented to
      allow for the acclimation to the respective preload. Using this approach, the participant
      becomes familiar with the taste profile along with the practice of consuming a breakfast
      'shake' so that the testing day more closely assimilates the habitual effects of the preload
      on appetite, satiety, and food intake.)

      On day 4, the participants will report to the research facility 1 h prior to their habitual
      breakfast time to complete each 4-h testing day. Upon arrival to the facility, each
      participant will become familiarized with the testing day procedures. At time -15 min, a
      baseline set of computerized appetite/satiety and cognitive function questionnaires will be
      completed. At time 0 min, the respective preload will be provided. Immediately following the
      first swallow of the preload, the participants will be given a questionnaire assessing the
      palatability. The participants will consume the preload within 10 min. Afterwards, the
      participants will continue to complete the questionnaires every 30 min throughout the 4-h
      postprandial period. In addition to these questionnaires, participants will complete a
      cognitive function paradigm at -30 min, +90 min, and +180 minutes in order to assess memory,
      executive function, attention, and reaction time. Throughout the day, the participants will
      also indicate if/when they would like to eat again. Regardless of their meal timing request,
      at 4-h post-breakfast, lunch will be provided. The participants will be given 30 min to
      "consume as much or as little as they wish until comfortably full." Following these
      procedures, the participants will be allowed to leave the facility. There will be a 3-7 day
      washout period between testing days.
    

Intervention name(s): Pea Protein-20g; Pea Protein-30g; Pea Protein-40g; Whey Protein-20g; Carbohydrate Control
Intervention type(s): Dietary Supplement; Dietary Supplement; Dietary Supplement; Dietary Supplement; Dietary Supplement
Intervention description(s): The study participants will be provided with breakfast preloads to consume. The energy content of the breakfast preload will be standardized to ~325 kcal. This preload will include 20 g pea protein, 5 g mixed protein (from yogurt and peanut-butter), 40 g carbohydrates, and 7 g fat. The preload is a yogurt-based (chocolate-peanut butter flavored) breakfast.; The study participants will be provided with breakfast preloads to consume. The energy content of the breakfast preload will be standardized to ~325 kcal. This preload will include 30 g pea protein, 5 g mixed protein (from yogurt and peanut-butter), 32 g carbohydrates, and 7 g fat. The preload is a yogurt-based (chocolate-peanut butter flavored) breakfast.; The study participants will be provided with breakfast preloads to consume. The energy content of the breakfast preload will be standardized to ~325 kcal. This preload will include 40 g pea protein, 5 g mixed protein (from yogurt and peanut-butter), 24 g carbohydrates, and 7 g fat. The preload is a yogurt-based (chocolate-peanut butter flavored) breakfast.; The study participants will be provided with breakfast preloads to consume. The energy content of the breakfast preload will be standardized to ~325 kcal. This preload will include 20 g whey protein, 5 g mixed protein (from yogurt and peanut-butter), 40 g carbohydrates, and 7 g fat. The preload is a yogurt-based (chocolate-peanut butter flavored) breakfast.; The study participants will be provided with breakfast preloads to consume. The energy content of the breakfast preload will be standardized to ~325 kcal. This preload will include 5 g mixed protein (from yogurt and peanut-butter), 59 g carbohydrates, and 7 g fat. The preload is a yogurt-based (chocolate-peanut butter flavored) breakfast.
Allocation: Randomized
Intervention model: Crossover Assignment
Intervention model description: tightly-controlled, randomized crossover design
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Prevention