Optogenetic induction of appetitive and aversive taste memories in Drosophila

Tastes are typically thought to evoke innate appetitive or aversive behaviours, prompting food acceptance or rejection. However, research in Drosophila melanogaster indicates that taste responses can be modified through experience-dependent changes in mushroom body circuits. In this study, we develop a novel taste learning paradigm using closed-loop optogenetics. We find that appetitive and aversive taste memories can be formed by pairing gustatory stimuli with optogenetic activation of sensory or dopaminergic neurons associated with reward or punishment. As with olfactory memories, distinct dopaminergic subpopulations drive the parallel formation of short- and long-term appetitive memories. Long-term memories are protein synthesis-dependent and have energetic requirements that are satisfied by a variety of caloric food sources or by direct stimulation of MB-MP1 dopaminergic neurons. Our paradigm affords new opportunities to probe plasticity mechanisms within the taste system and understand the extent to which taste responses are experience dependent.

Barriers and facilitators to successful implementation of sustainable school meals: a qualitative study of the OPTIMAT™-intervention

Background There is an urgent need to align human diets with goals for environmental sustainability and population health. The OPTIMAT™-intervention study was developed to implement and evaluate a nutritionally adequate and climate-friendly 4-week lunch menu in Swedish primary schools. This study aimed to explore pupils’ and kitchen staff’s experiences of the intervention and to identify barriers and facilitators to successful implementation of sustainable school meals. Methods An inductive manifest qualitative method was used. Nine focus group discussions (FGDs) were conducted, six with pupils in grades 5 (ages 10–11) and 8 (ages 14–15) (n = 29) and three with kitchen staff (n = 13). Data were analyzed using qualitative content analysis. Results Five main categories and 11 subcategories at a manifest level emerged. The five main categories were: 1) Experiences with the new menu, unfolding variations in how the new menu was received and kitchen staff’s experiences of working with it; 2) The meaning of diet sustainability, comprising pupils’ and kitchen staff’s perceptions about diet sustainability as a concept and part of their everyday lives; 3) Factors influencing plant-based food acceptance, covering aspects such as the influence of sensory factors, habits and peer pressure; 4) Opportunities to increase plant-based eating, including factors related to pupils’ and kitchen staff’s ideas for how to increase plant-based food acceptance; and 5) Need for a supportive environment to achieve dietary change, comprising pupils’ and kitchen staff’s thoughts on the importance of more knowledge, resources and involvement of stakeholders to eat more plant-based meals in schools. Conclusions Successful implementation of sustainable school meals would require more knowledge among pupils and kitchen staff. Staff also need more training in cooking of sustainable meals. Barriers among pupils could be tackled by introducing new plant-based meals more gradually and by more carefully considering the seasoning, naming and aesthetics of dishes. An increased leadership support for change and involvement of stakeholders from multiple levels within society will be key in the transition to sustainable school meals at scale. Trial registration The trial registration for the OPTIMAT™-intervention may be found at clinicaltrials.gov (NCT04168632 Fostering Healthy and Sustainable Diets Through School Meals (OPTIMAT)).

Factors Affecting Masticatory Satisfaction in Patients with Removable Partial Dentures

(1) Background: The degree of satisfaction with dental treatment varies among patients, and the discrepancy may exist between the patient’s subjective evaluation and the objective assessment. Further, the optimal methods for increasing patient satisfaction with mastication remain unclear. This study aimed to identify factors affecting masticatory satisfaction in patients with removable partial dentures. (2) Methods: A total of 132 participants (71.0 ± 9.0 years) were included. Masticatory satisfaction was assessed on a visual analog scale. An oral health survey was conducted to assess the number of functional teeth, missing tooth classification: Kennedy classification, occlusal support: Eichner classification, and removable partial dentures wearing jaw. Objective masticatory performance was assessed using gummy jelly, while subjective masticatory ability was assessed using food acceptance status and oral health-related quality of life. The associations of these factors with masticatory satisfaction were assessed. (3) Results: Masticatory satisfaction among removable partial denture wearers was not significantly associated with gender, age, denture wearing jaw, Kennedy classification, and occlusal support. The degree of masticatory satisfaction was significantly greater with higher levels of masticatory function: masticatory performance, food acceptance score, and OHIP-14 score. The OHIP-14 score was the only significant explanatory variable for masticatory satisfaction in the multiple regression analysis; the strongest associations were with the “psychological discomfort” and “physical disability” subscales (p = 0.02 and p = 0.005, respectively). (4) Conclusions: Masticatory satisfaction among removable partial denture wearers was strongly associated with oral health-related quality of life, in which the ability to eat meals comfortably with removable partial dentures is the most important determinant of masticatory satisfaction.

Eating Competence in First-Generation Students at a Northeastern, Public University

Objectives To assess differences in eating competence (EC) between first-generation students (FG) and students with 1 + parents who graduated from college (non-FG), in students 18–24 years old, at a large, northeastern, public university. Methods Data were collected between 2015–2020 from the College Health and Nutrition Assessment Survey, an ongoing, cross-sectional study at a northeastern university. Participants (n = 1974) completed the Eating Competence Satter Inventory (ecSI 2.0TM) and self-reported education status of both parents through an online survey (Qualtrics) during the 3rd or 4th week of classes. ecSI scores range from 0–48; eating competence was defined as ≥32. Subgroups within the ecSI include Eating Attitudes, Food Acceptance, Food Regulation and Contextual Skills. FG was defined if both parents did not obtain a college degree. ANCOVA evaluated differences between mean ecSI scores of FG vs. non-FG (n = 1478); age, gender, race, Pell Grant status, dining hall usage, athlete status, and available kitchen served as covariates. Results In this sample, 64.9% of participants were female students, 25.2% were FG, and had a mean age of 19.0 ± 0.02 years. FG students (n = 496) had modestly lower mean ecSI scores than non-FG students (32.9 ± 0.4 vs. 34.0 ± 0.3, P = 0.03. Subscale scores for Food Acceptance (0–9), Food Regulation (0–9) and Contextual Skills (0–12) were lower in FG students compared to non-FG students (5.1 ± 0.1 vs. 5.4 ± 0.7, P = 0.03, 6.4 ± 0.1 vs. 6.6 ± 0.1, P = 0.05, and 10.4 ± 0.1 vs. 10.9 ± 0.1, P = 0.003 respectively). Conclusions Results suggest FG students have lower EC scores than their non-FG counterparts; subscales suggest where FG students may need more support to achieve more favorable weight and health outcomes. More research in diverse communities of college students will help address the needs of FG students and strengthen outcomes for campus communities. Funding Sources New Hampshire Agriculture Experiment Stations and the USDA National Institute of Food and Agriculture Hatch Project.

Young Children's Food-Related Receptive Language and Acceptance of a Novel Food

Objectives Little inquiry has been undertaken regarding the interface of children's development of eating behaviors and their understanding of food-related (FR) words. Thus, we explored the relationship between young children's understanding of FR vocabulary (FR receptive language) and their acceptance of a novel food. Methods Caregivers (n = 35) and children ages 7–24 mo (n = 12 infants age <12 mo; n = 23 toddlers age ≥12 mo) participated in a study in which caregivers offered a novel food (nutrition supplement added to infant oatmeal) to their children. Novel food acceptance was measured as g consumed. The Communicative Development Inventory assessed caregiver perceptions of infants’ understanding of 154 words related to food and eating (FR receptive language). A linear regression model with FR receptive language, age (toddler vs. infant) and a FR receptive language-by-age interaction was used to predict acceptance of the novel food. Covariates included infant sex and BMI z-score and a p < 0.1 was chosen for this exploratory study. Results As expected, caregivers reported that infants understood fewer words as compared to toddlers (median [IQR]; 7 [13] vs. 33 [46], respectively). The relationship between FR receptive language and novel food acceptance differed by age (F = 8.08, p = 0.01). Among toddlers, greater FR receptive language (more food-related words understood) was associated with greater novel food acceptance (β [95% CI], 0.22g [−0.04, 0.49], p = 0.09). In younger infants, greater FR receptive language was associated with lower novel food acceptance (−0.80g [−1.53, −0.07], p = 0.03). Conclusions Receptive language facilitates children's understanding of their environment and contributes to shaping their behavior. Our preliminary findings suggest that greater FR receptive language may facilitate acceptance of novel food in toddlers. Younger infants were perceived to understand few words and may not have enough receptive language to positively influence food acceptance. Funding Sources This work was supported by the Government of Canada, as part of the Business Platform for Nutrition Research (BPNR) hosted by the Global Alliance for Improved Nutrition.

Early Temperamental Reactivity and Infants’ Responses to Novel Foods at 6 Months of Age

Objectives Since infant food acceptance is linked to diet quality and the development of food preferences, it is important to identify factors related to infants’ reactions to new foods. Temperament, or biologically-based differences in reactivity, has been associated with responses to new foods in childhood, but less research has focused on infancy. The objective of this study was to examine associations between infant temperament at 4 months and responses to new foods at 6 months. Methods Mother-infant dyads (n = 78; 62% male; 97% non-Hispanic white) participated in study visits when infants were 4 and 6 months of age. At 4 months, infants were video-recorded during tasks designed to elicit temperamental reactivity: 1) viewing 3 mobiles (containing 1, 3, and 7 stuffed bears) for 60 seconds each; and 2) listening to a recording of nonsense syllables spoken at 3 different volumes (Kagan & Snidman, 1991). Trained coders scored the presence of negative reactivity (i.e., crying) in 5-second intervals. An experimenter also rated the child's happiness and irritability during the visit on 9-point scales. At 6 months, mothers fed infants a new food (green beans or hummus). Trained coders scored the presence of negative affect (crying, fussing), positive behaviors (e.g., smiling, leaning forward), and food refusals (e.g., turning head) in 5-second intervals. Coded behaviors were summed and divided by the number of coded intervals. Results Regression models were used to test whether temperament (i.e., negative reactivity, happiness, and irritability) at 4 months predicted responses to the new food at 6 months. After controlling for age of solid food introduction (weeks), greater observed negative reactivity at 4 months was associated with more food refusals at 6 months (β = .30, p = .01). Higher happiness scores at 4 months were associated with less negative affect in response to the new food at 6 months (β = −.30, p = .01). Conclusions Temperamentally negative infants may be at risk for difficulties accepting new foods at the beginning of complementary feeding. Parents of these infants could benefit from strategies, such as repeated exposure, to increase new food acceptance. Future research should examine whether early difficulties with food acceptance persist across infancy and beyond. Funding Sources National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).

Nutritional versus behavioural intervention in children with avoidant/restrictive food intake disorder

Objective: The aim of the study was to determine the effectiveness of nutritional intervention compared to behavioural intervention to increase food acceptance and improve the nutritional status among children with avoidant/restrictive food intake disorder. Method: Six participants (3–4 years old) diagnosed with avoidant/restrictive food intake disorder took part in the study. They were randomly assigned to one of the two interventions, either a nutritional or behavioural approach. Results: The percentage of food acceptance increased for patients in the behavioural intervention group, but not for the nutritional intervention group (until later implementation of behavioural intervention). Moreover, the z-score for body mass index increased only after implementing behavioural intervention. The total score on the Montreal Children’s Hospital Feeding Scale decreased only after implementation of intervention based on behavioural approach. Inappropriate mealtime behaviour decreased across all participants after implementation of behavioural intervention. Discussion: Behavioural intervention seems to be promising for children with avoidant/restrictive food intake disorder to increase the oral intake of solid food and improve their growth.