Individual Differences in Children's Susceptibility to Overeating

描述（由申请人提供）：儿童和青少年肥胖率已达到17%的历史最高水平。迫切需要更好地了解控制儿童食欲和饮食的行为机制，并确定在当前致肥性食物环境中最容易暴饮暴食的儿童。致肥环境提供了获取大量美味、高能量食物的便利。食物的份量已被确定为成人和儿童能量摄入的重要决定因素。虽然在健康个体的异质群体中发现了份量效应，但一些证据表明，儿童对大份量食物的反应程度可能存在个体差异。例如，先前一项实验室研究的数据表明，超重和肥胖儿童在面对大份量食物时可能特别容易暴饮暴食。此外，份量大小对摄入量的影响程度也可能取决于儿童对食物的强化（或奖励）程度。食物的相对强化价值可能与环境因素相互作用，比如食物的分量大小，当有大量美味、能量密集的食物时，影响儿童的能量摄入。这项研究的主要目的是比较增加膳食中所有食物和饮料的份量对正常体重和肥胖儿童能量摄入的影响。第二个目的是测试那些发现食物相对于有吸引力的非食物替代品非常有益的孩子，在增加份量的反应中，是否会比那些发现食物不那么有益的孩子表现出更大的能量摄入增加。这项拟议的研究还将检查母亲喂养儿童的做法，例如用食物作为奖励，是否与儿童对食物的相对强化价值有关。先前的研究已经确定了儿童能量摄入的重要决定因素。在自由生活的条件下，环境因素与个体过度增重的倾向相互作用，从而影响饮食行为。通过检查环境影响和个人对暴饮暴食的易感性，我们可能能够确定暴饮暴食的风险因素，当这些决定因素中的任何一个单独检查时，这些因素可能会被掩盖。拟议的研究将扩展先前的研究结果，以测试环境因素，如食物份量大小，如何与个体体重状况差异或食物强化相互作用，从而影响儿童的能量摄入。这些数据将转化为制定预防和治疗儿童肥胖的饮食和环境战略。

DESCRIPTION (provided by applicant): The prevalence of childhood and adolescent obesity has reached an all-time high of 17%. There is a pressing need to better understand the behavioral mechanisms that control appetite and eating in children and to identify children who are most susceptible to overeating in the current obesogenic food environment. Obesogenic environments offer convenient access to large portions of palatable, energy-dense foods. The portion size of foods has been identified as an important determinant of energy intake in adults and children. While portion size effects have been found in heterogenous groups of healthy individuals, some evidence points to possible individual differences in the magnitude of children's responsiveness to large food portions. For example, data from a previous laboratory study suggest that overweight and obese children may be particularly vulnerable to overeating when presented with large food portions. Further, the magnitude of a portion size effect on intake may also depend on how reinforcing (or rewarding) children find food to be. It is possible that the relative reinforcing value of food may interact with environmental cues, such as the portion size of food, to affect children's energy intake when large portions of palatable, energy-dense foods are available. The primary aim of this study is to compare the effects of increasing the portion size of all foods and beverages served at a meal on energy intake in normal-weight and obese children. A second aim is to test if children who find food very reinforcing relative to an appealing nonfood alternative will show a significantly greater increase in energy intake in response to increasing portion sizes than will children who find food less reinforcing. The proposed study will also examine if maternal child feeding practices, such as using food as a reward, is associated with the relative reinforcing value of food in children. Previous studies have identified important determinants of energy intake in children. Under free-living conditions, environmental factors interact with individual predispositions to excessive weight gain to affect eating behavior. By examining environmental influences and individual-level susceptibility to overeating together, we may be able to identify risk factors for overeating that may be obscured when either one of these determinants is examined in isolation. The proposed study will extend previous findings to test how environmental factors, such as food portion size, may interact with individual differences in weight status or food reinforcement to affect energy intake in children. These data will translate to the development of dietary and environmental strategies for the prevention and treatment of childhood obesity. PUBLIC HEALTH RELEVANCE: In order to develop effective strategies to prevent and treat childhood obesity, there is a pressing need to identify modifiable eating traits and environmental factors which promote overeating in children. The proposed study will elucidate how children's weight status and relative reinforcing value of food may interact with aspects of the food environment (portion size) to affect energy intake.