The Effects of Consuming Whey Protein Polydextrose Snacks on Appetite and Energy Intake
Condition: Obesity
Study type: Interventional

Summary: 
      Developing functional foods that enhance satiety may be beneficial to individuals to help
      manage body weight.

      We have previously shown that consuming a mid-morning liquid preload with increasing
      proportion of energy derived from whey protein and addition of polydextrose reduced voluntary
      energy intake at a lunchtime meal compared to a liquid preload of the same energy content but
      lower in protein and containing no polydextrose.

      This study aims to investigate if these results can be replicated when the preload is in the
      form of a snack bar. We will also investigate whether the daily consumption of the snack bar
      has an effect on energy intake, subjective appetite and metabolic parameters compared to a
      control snack of the same energy but with a minimal protein content and without the addition
      of polydextrose.

      We hypothesize that the whey protein polydextrose snack will reduce voluntary energy intake
      at a subsequent test meal, suppress subjective appetite ratings compared with the control
      snack bar.
    

Detailed description: 
      Background:

      Developing functional food products that enhance satiety, suppress appetite, and reduce
      subsequent voluntary food intake to a greater extent than a similar energy matched food
      product, may be useful to help consumers adhere to energy restricted diets and optimize
      successful body weight management. A range of foods and food constituents have been reported
      to have the potential to produce short term changes in appetite and energy intake. However,
      the effects of consuming foods containing such ingredients on appetite, energy intake over
      the longer term is unclear.

      We have previously shown that consuming a mid-morning liquid preload with increasing
      proportion of energy derived from whey protein and addition of polydextrose reduced voluntary
      energy intake at a lunchtime meal compared to a liquid preload of the same energy content but
      lower in protein and containing no polydextrose.

      Aims:

      This study aims to investigate if previous findings can be replicated using solid snack bars
      containing whey protein and polydextrose. We will also investigate whether the daily
      consumption of the snack bar has an effect on energy intake, subjective appetite and
      metabolic and endocrine responses.

      Methods:

      Using a double blind, randomized cross-over design, 10 healthy lean male subjects will
      consume a whey protein-polydextrose bar and an iso-energetic control bar as a mid-morning,
      between-meal snack for 14 consecutive days. The two intervention phases will be separated by
      a 2-wk washout period. On the first (day 1) and the last day (day 15) of each intervention
      phase, subjective appetite, voluntary food intake, blood metabolite and endocrine responses
      to the snacks will be assessed under laboratory conditions. Additionally, participants will
      be asked to record free-living food intake on days 4, 8 and 12 of the intervention.
    

Intervention name(s): Whey-protein & polydextrose snack; Control snack
Intervention type(s): Dietary Supplement; Dietary Supplement
Intervention description(s): Subjects will consume one snack bar as a between-meal mid-morning snack daily for 15 days.; Subjects will consume one snack bar as a between-meal mid-morning snack daily for 15 days.
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Basic Science
Keywords: Energy intake; appetite; satiety; gut hormones