Factors Influencing Children's Short-Term Energy Compensation
Restricted (Penn State Only)
- Author:
- Reigh, Nicole
- Graduate Program:
- Nutritional Sciences
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- November 10, 2022
- Committee Members:
- Penny Kris-Etherton, Co-Chair of Committee
Barbara Rolls, Major Field Member
Jennifer Williams, Major Field Member
Kathleen Keller, Co-Chair & Dissertation Advisor
John Hayes, Outside Unit & Field Member
Tanja Kral, Special Member
Meg Bruening, Program Head/Chair - Keywords:
- childhood obesity
energy self-regulation
energy compensation
eating behavior
satiety
individual differences
pediatric nutrition - Abstract:
- As childhood obesity rates continue to increase, it is critical to identify factors that protect some children against excess weight gain. The ability to eat in response to homeostatic cues of hunger and fullness, rather than hedonic food cues, has been identified as one such factor and is often referred to as appetite self-regulation. However, this ability is highly variable and identifying sources of this variability may offer targets for obesity prevention and intervention strategies. This dissertation, therefore, aimed to examine various factors that may influence children’s short-term appetite self-regulation. The framework for this dissertation posited that appetite self-regulation requires a combination of bottom-up and top-down processes, both of which may be subject to a number of influences. While self-regulation likely has many facets, this dissertation focused on energy compensation as measured using a standard preloading paradigm. For this dissertation, three studies were designed to examine the effect of various factors on children’s energy compensation, including an appetite awareness intervention (Study 1), child-level individual differences (Study 2), and food characteristics, specifically food form (Study 3). Study 1 tested the effect of a technology-enhanced pilot intervention designed to improve children’s understanding of digestion, hunger, and fullness on energy compensation. Thirty-two children (mean age 4.9 ± 0.8 y) completed this within-subjects, pre-post design study that took place across 10 laboratory sessions. The intervention was conducted across weeks 4–7 in small groups focused on. In addition to energy compensation, knowledge of intervention concepts was assessed at baseline and follow-up. Linear mixed models were used to examine changes in short-term energy compensation and knowledge from baseline to follow-up. Knowledge related to the intervention improved from baseline to follow-up (3.5 ± 0.3 to 7.0 ± 0.3 correct responses out of a possible 10; P <0.001). Children’s energy compensation also improved from baseline to follow-up, as evidenced by a time-by-preload condition interaction (P = 0.02). However, this improvement was driven by boys who increased the adjustment for beverage energy content from baseline to follow-up (P = 0.04). Girls showed no change in energy compensation with the intervention (P = 0.58). The overall increase in knowledge, paired with the improvement in energy compensation in boys, suggests that this technology-enhanced intervention may be efficacious for some children. Given the sex differences in intervention response in Study 1, and individual differences observed across the wider span of this literature, Study 2 aimed to examine the effects of child sex, age, and weight status on energy compensation using a systematic review and meta-analysis. Findings from the meta-analysis indicated that, after an outlier was removed, children generally undercompensate for preload energy (p=0.008, k=13), though no differences were found by child sex (p=0.98, k = 9), age (p=0.97, k = 11), or weight status assessed continuously (p=0.58, k = 12). However, removal of the outlier resulted in a significant effect of weight status assessed categorically, such that children with overweight or obesity demonstrated poorer energy compensation than children with healthy weight (p=0.04). Additionally, preloading protocol variations were examined, and although none had effects on energy compensation, significant heterogeneity was detected. This highlights the importance of understanding how methodological factors may also influence energy compensation. Study 3 aims to contribute to the understanding of methodical differences on energy compensation by examining the effect of varying preload form (i.e., solid, semi-solid, liquid) on children’s subsequent intake. This study is ongoing and employs a within-subjects, crossover design in which children ages 4.5–6 years attend five laboratory visits, each ∼1 week apart. During each visit, children are presented with one of five possible preload conditions: apple slices, apple sauce, apple juice, apple juice sweetened with non-nutritive sweetener (NNS), or no preload. The order of preload conditions is pseudorandomized and counterbalanced across participants. Following consumption of the preload (or no preload), children consume a standardized ad libitum test meal of common foods for this age group. We hypothesize that children will demonstrate poorer short-term energy compensation (greater meal intake) in response to the liquid and semi-solid preloads compared to the solid preload. An additional aim of this study is the examine sex differences in energy compensation, as Study 2 found that no studies have examined these a priori. The research described in this dissertation contributes to our understanding of various factors that may influence children’s energy compensation and appetite self-regulation more generally, which has been implicated as an important facet of maintaining a healthy body weight. Studies 1 and 2 found that children generally undercompensate for preload energy, which challenges the common belief that children demonstrate accurate energy compensation. This has important implications given that many child feeding recommendations are built on the idea that children are able to self-regulate energy intake. The work in this dissertation also highlighted several gaps in the existing literature, including the effects of preloading protocol variations and lack of studies examining sex differences a priori. Though Study 3 aims to fill several of these gaps by examining the effect of preload form on energy compensation, as well as sex differences, much more research is needed to examine other effects of preload protocol. Standardizing methodologies across studies will make it possible to better characterize the effects of individual differences on energy compensation, so that more personalized and targeted intervention strategies may be developed.