Eating in the absence of hunger: Stability over time and associations with eating behaviours and body composition in children

Highlights

• A large proportion of children consumed some energy in the absence of hunger.

• Eating in the absence of hunger is stable over time.

• Eating in the absence of hunger is a risk factor for excessive energy intake.

• Eating in the absence of hunger may be linked with larger ideal portions of food.

• At ages 4.5 and 6 years eating in the absence of hunger was not linked to adiposity.

Abstract

Background/objectives

Eating in the absence of hunger (EAH) has been linked to obesity in adults and children. This study examined the stability of EAH in children between 4.5 and 6 years old, and associations with energy intake and portion selection, as well as cross-sectional and prospective associations with body composition.

Methods

The participants were 158 boys and girls from the Growing Up in Singapore Towards healthy Outcomes cohort. At ages 4.5 and 6 years old children were provided lunch ad libitum, and immediately afterwards were exposed to palatable snacks to measure energy intake in the absence of hunger. At age 6 children completed an additional computer-based task to measure ideal portion size, where they selected pictures of the portions they would like to eat across eight foods. Measures of anthropometry (height/weight/skinfolds) were collected at both ages.

Results

Children who consumed energy during the EAH task at age 4.5 years were 3 times more likely to also do so at age 6 years. Children with high EAH intakes at age 4.5 years had high EAH intakes at age 6, highlighting stability of this behaviour over time. Energy consumed at lunch was unrelated to energy consumed during the EAH task, but children who ate in the absence of hunger cumulatively consumed more energy over lunch and the EAH task. Children who showed EAH tended to select larger ideal portions of foods during the computer task. EAH was not associated with measures of body composition.

Conclusions

EAH is a stable behavioural risk factor for increased energy intake, but was not associated with body composition in this cohort. The majority of children ate in the absence of hunger, suggesting that interventions aimed at reducing responsiveness to external food cues could help to reduce energy intakes.

Trial Registry Number: NCT01174875; https://clinicaltrials.gov/.

Introduction

Increasing rates of obesity observed since the mid-20th century have been partially attributed to changes in the food environment, abundant in affordable, palatable and energy-dense foods, often served in large quantities, that promote greater energy intakes within and around meal times [25,33]. Responsiveness to environmental food cues like the sight or smell of foods can be reflected in physiological and behavioural responses. This includes increased salivation and endocrine changes, as well as increases in subjective appetite and selecting and consuming larger quantities of food [5,14,16,22,36,38]. Though the “obesogenic environment” is thought to promote overconsumption, there are individual differences in appetitive traits and responsiveness to environmental food cues, which emerge early in life and stabilise during development, and help to explain why not everybody overconsumes energy and develops obesity [32].

Eating despite being full when exposed to palatable foods is a behavioural expression of heightened food responsiveness that could put children at risk of overconsuming calories. This behaviour can be empirically measured by exposing children to freely available snacks immediately after consuming a meal to satiety, in what Fisher and Birch [19] conceptualised as the ‘Eating in the Absence of Hunger’ (EAH) paradigm. The EAH paradigm is primarily thought to test a child's responsiveness to external palatable food cues, however increased energy intake during this task might also reflect some aspects of satiety responsiveness [9], disinhibited eating [44,45] and emotional arousal [46]. Moreover, the propensity to eat without hunger has hereditary and genetic components [20,48] that are likely to be perpetuated by certain parental feeding practices, such as restriction of foods [12,18], indicating the potential for large individual differences in this behaviour.

EAH has been shown to be more prevalent among children with overweight/obesity, or at higher familial risk for overweight/obesity [15,23,24,27,35]. However, many of the studies examining the link between EAH and obesity in paediatric populations have been conducted only on girls, and those conducted on both boys and girls suggest that this relationship could be dependent on the child's sex and age (for full review see [31]). Studies conducted with girls show that EAH is stable over time [19] and is linked to higher adiposity and prospective weight gain [41]. Among studies which considered both sexes, some showed that EAH is linked to higher adiposity in girls, but not boys [12], while others demonstrated the links with adiposity among boys, but not girls [26]. Further research is needed to examine the stability of this behaviour among children from both sexes, and the potential links with body composition and weight gain over time.

Children who eat in the absence of hunger may be at risk for overconsuming calories and developing obesity, but it is unclear whether they also demonstrate other behaviours associated with higher energy intakes, such as selecting and consuming larger portions of food. Previous research demonstrated that among 4 year old children EAH was linked with increased intake of foods at lunch, particularly when children were presented with larger portions of food to consume [22]. Children, like adults, eat more when they are served larger portions of food [2,21,29,43] and it has been suggested that encouraging children to self-serve their food could be a strategy to promote self-regulation and reduce intake [4]. However, there are individual differences in self-served food portions and not all children eat less when given the opportunity to serve themselves at a meal [7,17,40]. It is possible that selecting larger portions of food could reflect a similar dimension of food cue responsiveness as that captured by the EAH paradigm, and highly food responsive children may select and consume larger portions of different foods, not just palatable snacks.

To better understand the link between EAH and weight status during childhood, the current study sought to test whether EAH is stable over time and is associated with larger portion selection, increased energy intake and adiposity in children. Specifically, we first examined whether EAH is a stable behaviour between 4.5 and 6 years of age (1). We then investigated the links between EAH and (2) energy consumed during an ad libitum lunchtime meal, (3) child selected ideal portion sizes across a range of foods (4) and child adiposity. We hypothesised that EAH would show stability from 4.5 to 6 years. We further predicted that children who ate in the absence of hunger would consume more energy at lunch, would have higher cumulative energy intakes across the two eating occasions and would select larger portions of foods on a computer based portion selection task. Finally, we predicted that EAH would be associated with higher BMI and higher adiposity at both time points, and children who ate in the absence of hunger at age 4.5 years would have higher BMI and greater increase in BMI between the ages 4.5 and 6 years.