The influence of expected satiety on portion size selection is reduced when food is presented in an ‘unusual’ meal context

"A good way to start the day": UK-based parents' views about offering vegetables to children for breakfast

Children in the UK do not eat enough vegetables for optimal health and development; therefore, considering methods to increase children's vegetable intake is critical. Currently, if UK children are offered vegetables to eat, this typically occurs at midday/evening meals, and/or for snacks - children are seldom offered vegetables at breakfast time, even though there is no medical, nutritional, or physiological reason not to. Therefore, this study aimed to explore the views and experiences of parents in relation to offering children (aged 18 months to four years) vegetables to eat at breakfast time. Semi-structured interviews were conducted with 18 parents (aged 27-51 years) who were asked for their opinions about offering vegetables to children at breakfast time, and about their perceptions of their child(ren)'s behaviours in relation to vegetables at breakfast. A thematic analysis of the data identified the following themes/sub-themes relating to parents' views and experiences: 1) willingness - there was widespread willingness amongst parents to offer their chid(ren) vegetables at breakfast time; 2) barriers - relating to social/behavioural norms (parent/family and societal), practical challenges, and vegetables being commonly disliked by children; 3) facilitators - relating to young children not yet having developed social norms around foods, various practical solutions, and the need for information and awareness campaigns to highlight how and why vegetables can be incorporated into children's breakfasts. These encouraging findings for optimising children's health via this novel approach suggest that further research and dissemination around the value of offering children vegetables for breakfast is required.

Does social-norm messaging influence expected satiety and ideal portion-size selection?

A person's perception of how long a food will stave off hunger (expected satiety) and the ideal amount to consume (ideal portion size) are both influenced by food-to-mealtime norms. Here, we examine whether social norms can modulate this effect, in three experimental studies. In study 1 (n = 235) participants were exposed to a social norm suggesting most people enjoyed consuming pasta for breakfast. There was a main effect of food-to-mealtime congruence for expected satiety and ideal portion size (p < 0.001) - participants selected a smaller portion of pasta for breakfast (vs. lunch) - but there were no other main effects/interactions (p ≥ 0.15). Study 2 (n = 200) followed the same approach as study 1, but sought to examine whether the typical volume of food consumed at breakfast and lunch needed to be controlled. Again, there was a main effect of congruence (the same pattern) (p ≤ 0.02) but no other main effects/interactions (p ≥ 0.73). Study 3 (n = 208) followed the same approach as study 2, but the social-norm message was changed to suggest that most people who eat pasta for breakfast found it effectively reduced their hunger. Again, there was a main effect of congruence (the same pattern) (p < 0.001) but no other main effects/interaction (p ≥ 0.26). These studies provide further evidence for the food-to-mealtime effect, but do not provide any evidence that a single, simple social-norm statement can modulate expected satiety or ideal portion size, or interact with the food-to-mealtime effect.

The Impact of Modifiable Preoral Factors on Swallowing and Nutritional Outcomes in Healthy Adults: A Scoping Review

PURPOSE

Swallowing has previously been characterized as consisting of four phases; however, it has become apparent that these four phases are not truly discrete and may be influenced by factors occurring prior to bolus entrance into the oral cavity (i.e., preoral factors). Still, the relationship between these factors and swallowing remains poorly understood. The aim of this review was to synthesize and characterize the literature pertaining to the influence of preoral factors on swallowing and nutritional outcomes in healthy individuals.

METHOD

We performed a scoping review, searching the databases of PubMed, CINAHL, Cochrane, and Scopus. Search terms included those related to swallowing, experience of preoral factors, and exclusionary terminology to reduce animal and pediatric literature. Our initial search revealed 5,560 unique articles, of which 153 met our inclusionary criteria and were accepted into the review.

RESULTS

Of the accepted articles, 78% were focused exclusively on nutritional outcomes, 17% were focused on both swallowing and nutritional outcomes, and 5% were focused on solely swallowing outcomes. Of the preoral factors examined, 99% were exteroceptive in nature (17% olfactory, 44% visual, 21% auditory, 7% tactile, 11% other), while 1% were proprioceptive in nature.

CONCLUSIONS

This review supports the influence of preoral factors on swallowing and nutritional outcomes. However, there is a large emphasis on the visual modality and on nutritional outcomes. Nearly none of the literature found in this review directly measured swallowing safety, efficiency, or physiology. Future work will benefit from a larger focus on proprioceptive preoral factors as they relate to swallowing outcomes.

Offering vegetables to children at breakfast time in nursery and kindergarten settings: the Veggie Brek feasibility and acceptability cluster randomised controlled trial

BACKGROUND

In many Westernised countries, children do not consume a sufficient amount of vegetables for optimal health and development. Child-feeding guidelines have been produced to address this, but often only promote offering vegetables at midday/evening meals and snack times. With guidance having limited success in increasing children's vegetable intake at a population level, novel approaches to address this must be developed. Offering vegetables to children at breakfast time in nursery/kindergarten settings has the potential to increase children's overall daily vegetable consumption as children typically attend nursery/kindergarten and many routinely eat breakfast there. However, the feasibility and acceptability of this intervention (Veggie Brek) to children and nursery staff has not been investigated.

METHODS

A feasibility and acceptability cluster randomised controlled trial (RCT) was undertaken in eight UK nurseries. All nurseries engaged in one-week baseline and follow-up phases before and after an intervention/control period. Staff in intervention nurseries offered three raw carrot batons and three cucumber sticks alongside children's main breakfast food each day for three weeks. Control nurseries offered children their usual breakfast. Feasibility was assessed by recruitment data and nursery staff's ability to follow the trial protocol. Acceptability was assessed by children's willingness to eat the vegetables at breakfast time. All primary outcomes were assessed against traffic-light progression criteria. Staff preference for collecting data via photographs versus using paper was also assessed. Further views about the intervention were obtained through semi-structured interviews with nursery staff.

RESULTS

The recruitment of parents/caregivers willing to provide consent for eligible children was acceptable at 67.8% (within the amber stop-go criterion) with 351 children taking part across eight nurseries. Both the feasibility and acceptability of the intervention to nursery staff and the willingness of children to consume the vegetables met the green stop-go criteria, with children eating some part of the vegetables in 62.4% (745/1194) of instances where vegetables were offered. Additionally, staff preferred reporting data using paper compared to taking photographs.

CONCLUSIONS

Offering vegetables to children at breakfast time in nursery/kindergarten settings is feasible and acceptable to children and nursery staff. A full intervention evaluation should be explored via a definitive RCT.

TRIAL REGISTRATION

NCT05217550.

Implicit satiety goals and food-related expectations predict portion size in older adults: Findings from the BAMMBE cohort

Portion size selection is an indicator of appetite and within younger adults, is predicted by factors such as expected satiety, liking and motivations to achieve an ideal sensation of fullness (i.e., implicit satiety goals). Currently, there is limited research available on the determinants of portion size selection within older adults. Therefore, the current study aimed to examine the relationship between individual differences in implicit satiety goals, food-related expectations, and portion size selection in older adults. Free-living older adult Singaporeans (N = 115; Nmales = 62; age: M = 66.21 years, SD = 4.78, range = 60-83 years) participated as part of the Brain, Ageing, Microbiome, Muscle, Bone, and Exercise Study (BAMMBE). Participants completed questionnaires on their subjective requirements for experiencing different states of satiety and food-related expectations (i.e., liking, how filling) as well as a computerised portion size selection task. Using a multiple regression, we found that goals to feel comfortably full (B = 3.08, SE = 1.04, t = 2.96, p = .004) and to stop hunger (B = -2.25, SE = 0.82, t = -2.75, p = .007) significantly predicted larger portion size selection (R2 = 0.24, F(4,87) = 6.74, p < .001). Larger portion sizes (R2 = 0.53, F(5,90) = 20.58, p < .001) were also predicted by greater expected satiety (B = 0.47, SE = 0.09, t = 5.15, p < .001) and lower perceptions of how filling foods are (B = -2.92, SE = 0.77, t = -3.79, p < .001) but not liking (B = -0.09, SE = 0.91, t = -0.10, p = .925) or frequency (B = -18.42, SE = 16.91, t = -1.09, p = .279) of consumption of target foods. Comparing our findings to results of studies conducted with younger adults suggests the influence of factors such as satiety related goals on portion size selection may change with ageing while the influence of other factors (e.g., expected satiety/fullness delivered by foods) may remain consistent. These findings may inform future strategies to increase/decrease portion size accordingly to ensure older adults maintain an appropriate healthy weight.

Would offering vegetables to children for breakfast increase their total daily vegetable intake?

The consumption of vegetables is vitally important for children's health and development. However, in many Westernised countries, most children do not eat sufficient quantities of vegetables and consume many energy-dense and high-sugar foods; a health behaviour associated with the onset of non-communicable diseases. To address this important public health concern, it is necessary to think 'outside the box' and consider innovative and pragmatic ways to increase children's daily vegetable intake. In many countries, caregivers implementing best-practice child feeding methods typically offer children vegetables at lunch, dinner and for snacks. It is unusual for children to be routinely offered vegetables for breakfast, yet there is no nutritional, physiological or medical reason why vegetables should not be eaten at breakfast. Indeed, in some countries, children frequently consume vegetables for breakfast. Increasing children's exposure to vegetables at breakfast from an early age would allow for the development of a positive association between eating vegetables and breakfast, thus providing another opportunity in the day where vegetables might be regularly consumed by children. In this paper, we propose a rationale for why vegetables should be routinely offered to young children at breakfast time in countries where this may not be the norm. Future research assessing the feasibility and acceptability of such a public health intervention would provide health policy agencies with evidence about a potentially effective and easily implementable approach for increasing children's vegetable intake, thus improving their overall nutritional status, as well as their heath and development.

Portions selected to stave off hunger are reduced when food is presented in an 'unusual' food-to-mealtime context: An implication for implicit satiety drivers

Research suggests that the role of expected satiety in influencing portion-size selection is reduced when food is presented in unusual food-to-mealtime contexts; however, the underlying mechanism has not been explored. Other research has revealed that different implicit satiety drivers (e.g., to stop momentary hunger or obtain complete fullness) are associated with different perceived levels of stomach fullness, portion-size selections and can change on instruction. The current study explored whether changes in expected satiety and ideal portions in congruous vs incongruous contexts can be explained by changes in implicit satiety drivers. Another aim was to investigate a previous exploratory finding suggesting that portions selected to stave off hunger are reduced when foods are presented in unusual food-to-mealtime contexts. At two trials (breakfast/lunch), participants (n = 40) selected a portion of typical lunch (pasta) and breakfast (porridge) foods via a psychophysical computer-based method 1) to stave off hunger for 5 h, and 2) as an ideal portion. Participants also indicated their perceived level of stomach fullness associated with 1) each portion, and 2) five implicit satiety drivers. Results revealed that a smaller average portion was selected to stave off hunger in incongruous (vs congruous) food-to-mealtime contexts (531 ± 229 vs 575 ± 236 kcal) (p = 0.008). This suggests that expected satiety is influenced by momentary context; foods are perceived to be more satiating when consumed in unusual (vs usual) contexts. Results also showed that implicit satiety drivers are malleable in regard to the portion size associated with a perceived level of stomach fullness and that this can vary contextually. These findings provide initial evidence to explain the psychological mechanism underlying the contextual differences observed in portion-size selections. Future work should explore longer-term impacts of consuming foods in unusual contexts.

Current appetite influences relative differences in the expected satiety of foods for momentary, but not hypothetical, expected satiety assessments

Research has shown that expected satiety is highly associated with portion-size selection and can vary (kcal-for-kcal) significantly between foods. However, research has not adequately investigated whether current appetite influences relative differences in the expected satiety of foods. This is important to explore to better understand how current motivational state influences food choice and portion selection. This study used 'hypothetical' and 'momentary' expected-satiety assessments to understand whether methods requiring a reflection on current motivational state [momentary] versus more hypothetical considerations when assessing expected satiety can influence the interpretation of results. It was hypothesised that current appetite would only influence relative differences in expected satiety between foods for momentary, but not hypothetical, expected satiety assessments. Participants (n = 54) were shown images of twelve foods, once when hungry and once when full. In each case, they selected a portion for each food to 1) match the expected satiety of a fixed-portion 'standard' food [hypothetical], and 2) stave off hunger until their next meal [momentary]. Results showed that the relative between-food comparison of expected satiety was stable for hypothetical (p=.73) but not momentary assessments (p<.001) suggesting that while current motivational state may influence food choice and portion selection in the moment, more generalised comparisons of the satiating abilities of foods (learned over a longer period) remain stable. This is important 1) for methods in future studies, as immediate dietary intake does not appear to influence hypothetical expected satiety, thus dietary control is not necessary before participants undertake these assessments, and 2) as it confirms that difficulties associated with dietary regulation may not be due to inaccurate hypothetical judgements about foods, but instead appear to be influenced by contextual nuances that occur in the moment.

Testing an online measure of portion size selection: a pilot study concerned with the measurement of ideal portion size

BACKGROUND

Portion size is known to be a key driver of food intake. As consumed portions are often pre-planned, 'ideal portion size'-an individual's preferred meal size selected prior to eating-has been identified as a strong predictor of actual consumption. However, assessments of ideal portion size have predominantly relied on laboratory-based computer tasks, limiting use online. Therefore, this cross-sectional study sought to pilot test the validity of a web-based tool to measure ideal portion size.

METHODS

In an online study (N = 48), participants responded to images of a range of foods. Each food was photographed in a series of different portions and loaded into an 'image carousel' that would allow participants to change the size of the displayed portion by moving a slider left-to-right. Using this image carousel, participants selected their ideal portion size. They also completed measures of expected satiety and expected satiation and self-reported their age and body mass index (BMI). A non-parametric correlation matrix was used to explore associations between ideal portion size and identified predictors of food intake.

RESULTS

Supporting convergent validity of this measure, ideal portion size was significantly correlated with expected satiety (rs = .480) and expected satiation (rs = -.310) after controlling for effects of baseline hunger and fullness, consistent with past research. Similarly, supporting divergent validity of this measure, ideal portion size was not significantly correlated with age (rs = -.032) or BMI (rs = -.111,).

CONCLUSIONS

Pilot results support the validity of this web-based portion size selection tool used to measure ideal portion size, though further research is needed to validate use with comparisons to actual food intake.

Negative energy balance during military training: The role of contextual limitations

During multiday training exercises, soldiers almost systematically face a moderate-to-large energy deficit, affecting their body mass and composition and potentially their physical and cognitive performance. Such energy deficits are explained by their inability to increase their energy intake during these highly demanding periods. With the exception of certain scenarios in which rations are voluntarily undersized to maximize the constraints, the energy content of the rations are often sufficient to maintain a neutral energy balance, suggesting that other limitations are responsible for such voluntary and/or spontaneous underconsumption. In this review, the overall aim was to present an overview of the impact of military training on energy balance, a context that stands out by its summation of specific limitations that interfere with energy intake. We first explore the impact of military training on the various components of energy balance (intake and expenditure) and body mass loss. Then, the role of the dimensioning of the rations (total energy content above or below energy expenditure) on energy deficits are addressed. Finally, the potential limitations inherent to military training (training characteristics, food characteristics, timing and context of eating, and the soldiers' attitude) are discussed to identify potential strategies to spontaneously increase energy intake and thus limit the energy deficit.