Portion Manipulation and Portion Education Intervention Research

Evidence suggests that children undergo important physical and behavioral changes when they are approximately 3-5 years. These changes include being affected by the amount of food they are served, with larger portions of food served resulting in greater dietary intake.

A systematic review was undertaken to determine: 1) what researchers have found concerning the effect of varying portion sizes with children and 2) what evidence exists regarding the effects of educating adults to estimate portion sizes. This evidence led to the conduct of a randomized controlled trial (RCT) to determine which of two portion education interventions would result in changed dietary intake of preschool children..

A heterogeneous sample of 35 children and their parents participated in this pre-test/post-test RCT. General educational nutritional information was provided to all participant parents. The information ended with one of two suggested methods of providing food to their children. Following a 3-week period of time parents were post-tested. Analyses indicate that there were no significant differences between the dietary intake of the children at post-test; however, there was a large effect size of the intervention for all participant parents and children from pre- to post-testing, results that were statistically significant. More specifically, the amount of food served decreased from pre- to post- test and approached the recommended daily allowance. And the distribution of calories for each macronutrient more closely approximated recommended percentages. Children’s dietary intake of macronutrients (gm/day) was directly related to the amount served.

This research team suggests that these results are likely to have occurred as a result of teaching parents about macronutrient value and enhancing their skills of monitoring their child’s dietary intake. The parents engaged in the enactment of their skills regardless of the method by which they served food to their child.