Switching between foods: A potential behavioral phenotype of hedonic hunger and increased obesity risk in children

PACE: a Novel Eating Behavior Phenotype to Assess Risk for Obesity in Middle Childhood

BACKGROUND

Behavioral phenotypes that predict future weight gain are needed to identify children susceptible to obesity.

OBJECTIVES

This prospective study developed an eating behavior risk score to predict change in adiposity over 1 y in children.

METHODS

Data from 6 baseline visits (Time 1, T1) and a 1-y follow-up visit (Time 2, T2) were collected from 76, 7- to 8-y-old healthy children recruited from Central Pennsylvania. At T1, children had body mass index (BMI) percentiles <90 and were classified with either high (n = 33; maternal BMI ≥30 kg/m2) or low (n = 43; maternal BMI ≤25 kg/m2) familial risk for obesity. Appetitive traits and eating behaviors were assessed at T1. Adiposity was measured at T1 and T2 using dual-energy x-ray absorptiometry, with a main outcome of fat mass index (FMI; total body fat mass divided by height in meters squared). Hierarchical linear regressions determined which eating measures improved prediction of T2 FMI after adjustment for covariates in the baseline model (T1 FMI, sex, income, familial risk, and Tanner stage).

RESULTS

Four eating measures-Portion susceptibility, Appetitive traits, loss of control eating, and eating rate-were combined into a standardized summary score called PACE. PACE improved the baseline model to predict 80% variance in T2 FMI. PACE was positively associated with the increase in FMI in children from T1 to T2, independent of familial risk (r = 0.58, P < 0.001). Although PACE was higher in girls than boys (P < 0.05), it did not differ by familial risk, income, or education.

CONCLUSIONS

PACE represents a cumulative eating behavior risk score that predicts adiposity gain over 1 y in middle childhood. If PACE similarly predicts adiposity gain in a cohort with greater racial and socioeconomic diversity, it will inform the development of interventions to prevent obesity. This trial was registered at clinicaltrials.gov as NCT03341247.

Switching between foods is reliably associated with intake across eating events in children

Emerging evidence suggests switching between foods during an eating event is positively associated with intake. However, it is unclear whether switching is a stable behavior that predicts consumption across multiple eating events. The current study explored whether switching is consistent within children and reliably associated with intake across varied eating events. We analyzed data from 88 (45 F), 7-8-year-old children without obesity participating in a 7-visit prospective cohort study (ClinicalTrials.gov NCT03341247). Amount consumed and energy intake were measured at 4 separate meals of foods that varied by portion sizes served. Meals included macaroni and cheese, chicken nuggets, broccoli, and grapes (all 0.7-2.5 kcal/g). Children's intake was also assessed during 2 eating in the absence of hunger (EAH) paradigms separated by ≥ 1 year. The EAH paradigm included 9 sweet and savory snack foods (all 1.9-5.7 kcal/g). All eating events were video-recorded and switching was assessed by counting the number of times a child shifted between different food items. Results demonstrated that switching was reliably associated with intake at both the meals and the EAH paradigms (ps < 0.01). Specifically, at meals each additional switch was associated with 11.7 ± 1.3 kcal (7.7 ± 0.8 g) more consumed, and during EAH each additional switch was associated with 8.1 ± 2.1 kcal (2.1 ± 0.5 g) more consumed. Switching behavior was also moderately consistent across meals (ICC = 0.70) and EAH paradigms (ICC = 0.50). However, switching at meals was not related to switching at EAH paradigms. This study demonstrates the consistency of switching behavior and its reliable association with intake across eating events, highlighting its potential to contribute to chronic overconsumption and childhood obesity.

Sex-Dependent Metabolic Effects in Diet-Induced Obese Rats following Intermittent Fasting Compared with Continuous Food Restriction

Recently, intermittent fasting has gained relevance as a strategy to lose weight and improve health as an alternative to continuous caloric restriction. However, the metabolic impact and the sex-related differences are not fully understood. The study aimed to compare the response to a continuous or intermittent caloric restriction in male and female rats following a previous induction of obesity through a cafeteria diet by assessing changes in body weight, energy intake, metabolic parameters, and gene expression in liver hepatic and adipose tissue. The continuous restriction reduced the energy available by 30% and the intermittent restriction consisted of a 75% energy reduction on two non-consecutive days per week. The interventions reduced body weight and body fat in both sexes, but the loss of WAT in females was more marked in both models of caloric restriction, continuous and intermittent. Both caloric restrictions improved insulin sensitivity, but more markedly in females, which showed a more pronounced decrease in HOMA-IR score and an upregulation of hepatic IRS2 and Sirt1 gene expression that was not observed in males. These findings suggest the fact that females are more sensitive than males to reduced caloric content in the diet.

Poorer inhibitory control was related to greater food intake across meals varying in portion size: A randomized crossover trial

Individuals eat more food when larger portions are served, and this portion size effect could be influenced by inhibitory control (the ability to suppress an automatic response). Inhibitory control may also relate to obesogenic meal behaviors such as eating faster, taking larger bites, and frequent switching between meal components (such as bites of food and sips of water). In a randomized crossover design, 44 adults ate lunch four times in the laboratory. Lunch consisted of a pasta dish that was varied in portion size (400, 500, 600, or 700 g) along with 700 g of water. Meals were video-recorded to assess meal duration and bite and sip counts, which were used to determine mean eating rate (g/min), mean bite size (g/bite), and number of switches between bites and sips. Participants completed a food-specific stop-signal task, which was used to calculate Stop-Signal Reaction Time (SSRT). Across participants, SSRT values ranged from 143 to 306 msec, where greater SSRT indicates poorer inhibitory control. As expected, serving larger portions increased meal intake (p < 0.0001); compared to the smallest portion, intake of the largest increased by 121 ± 17 g (mean ± SEM). SSRT did not moderate the portion size effect (p = 0.34), but individuals with poorer inhibitory control ate more across all meals: 24 ± 11 g for each one SD unit increase in SSRT (p = 0.035). SSRT was not related to eating rate or bite size (both p > 0.13), but poorer inhibitory control predicted greater switching between bites and sips, such that 1.5 ± 0.7 more switches were made during meals for each one SD unit increase in SSRT (p = 0.03). These findings indicate that inhibitory control can contribute to overconsumption across meals varying in portion size, potentially in part by promoting switching behavior.