The Lunch Study: the Combined Effects of Food Texture and Portion Size on Intake
Condition: Satiation
Study type: Interventional

Summary: 
      Meal size is strongly influenced by a number of external features of the food environment
      which can promote over-consumption, such as the availability of palatable energy dense foods
      and large portion sizes. The current research aimed to investigate whether natural food-based
      differences in texture could be used to slow down eating rate and reduce intake from large
      portions.

      A four-session randomised crossover study assessed the effect of faster vs. slower eating
      rate, achieved through manipulating food texture, on ad-libitum consumption (weight and
      calories) of a meal, alone and in combination with variations in meal portion size (regular
      vs. large)
    

Detailed description: 
      The current obesogenic environment is characterized by the abundance of palatable and high
      energy dense foods. Eating from large portions can promote sustained overcompensation at meal
      times. On the other hand, eating at a slower rate has been shown to reduce meal size, and
      food-based texture differences can slow eating rate. It is possible that texture-based
      differences in eating rate could be used to reduce energy intake in of foods that are served
      in large portions.

      This study was conducted to quantify the effect of eating rate (fast vs. slow) on ad-libitum
      consumption of a meal, alone and in combination with variations in portion size (100 % 700 g
      vs 150 % 1050 g). The meal combinations were as follows:

      Meal 1: thin/100% portion; Meal 2: thin/150% portion; Meal 3: thick/100% portion; Meal 4:
      thick /150% portion

      Participants consumed the four test meals over four non-consecutive test sessions at the
      Clinical Nutrition Research Centre, with at least three days washout between each session.
      Each part followed a completely randomised full crossover design.

      The primary objective was to assess ad libitum intake (both kcal and g) of the test meals,
      depending on the combination of food texture and energy density.

      The secondary objectives were to assess the eating rate, oral processing characteristics,
      changes in rated appetite up to 90 minutes post-consumption and energy intake (kcal) for the
      rest of the test day (food diary), as a function of the test meal texture and energy density
    

Intervention name(s): Thin/100% Portion; Thin/150% Portion; Thick/100% Portion; Thick/150% Portion
Intervention type(s): Other; Other; Other; Other
Intervention description(s): Thin textured rice meal (ground rice grains) served in a regular portion size (100 %: 700g); Thin textured rice meal (ground rice grains) served in a larger portion size (150 %: 1050g); Thick textured rice meal (whole rice grains) served in a regular portion size (100 %: 700g); Thick textured rice meal (whole rice grains) served in a larger portion size (150 %: 1050g)
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Single (Participant)
Primary purpose: Basic Science
Keywords: Meal size