Effects of Oro-Sensory Exposure on Satiation and Underlying Neurophysiological Mechanisms-What Do We Know So Far?

Abnormal functional connectivity of the reward circuit associated with early satiety in patients with postprandial distress syndrome

Postprandial distress syndrome (PDS) is the most common functional dyspepsia (FD) subtype. Early satiety is one of the cardinal symptoms of the PDS subtype in FD patients. The heterogeneity of symptoms in FD patients hampered therapy for patients based on specific symptoms, necessitating a symptom-based understanding of the pathophysiology of FD. To investigate the correlation between reward circuit and symptom severity of PDS patients, seed (Nucleus accumbens, NAc, a key node in the reward circuit) based resting-state functional connectivity (FC) was applied in the neuroimaging data analysis. The results demonstrated that the patients with PDS manifested strengthened FC between NAc and the caudate, putamen, pallidum, amygdala, hippocampus, thalamus, anterior cingulate cortex (ACC), and insula. Moreover, the FC between NAc and ACC, insula, thalamus, and hippocampus exhibited significant positive associations with symptom severity. More importantly, the strengthened FC between NAc and the ACC, insula, amygdala, and hippocampus were found associated with the early satiety symptom of patients with PDS. This study indicated that the altered FC of reward circuit regions may play a role in the pathophysiology of patients with PDS, and some of the aberrant NAc-based FC within the reward circuit were more related to the early satiety of patients with PDS. These findings improve our symptom-based understanding of the central pathophysiology of FD, lay the groundwork for an objective diagnosis of FD, and shed light on the precise prescription for treating FD based on symptoms.

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.

Child eating behaviors are consistently linked to intake across meals that vary in portion size

Prior studies evaluating a single meal in children characterized an "obesogenic" style of eating marked by larger bites and faster eating. It is unclear if this style is consistent across portion sizes within children so we examined eating behaviors in 91 children (7-8 years, 45 F) without obesity (BMI<90th percentile). Children consumed 4 ad libitum meals in the laboratory consisting of chicken nuggets, macaroni, grapes, and broccoli that varied in portion size (100%, 133%, 166%, 200%) with a maximum of 30 min allotted per meal. Anthropometrics were assessed using age and sex adjusted body mass index (BMI) percentile and dual energy x-ray absorptiometry. Bites, sips, active eating time, and meal duration were coded from meal videos; bite size (kcal and g/bite), proportion of active eating (active eating time/meal duration), and eating rate (kcal and g/meal duration) were computed. Intraclass correlation coefficients (ICC) showed that most eating behaviors were moderately consistent across portions (>0.50). The consistency of associations between eating behaviors and total meal intake and adiposity were assessed with general linear models adjusted for food liking, pre-meal fullness, age, and sex. Across all portions, more bites, faster eating rate, and longer meal duration were associated with greater intake. While higher BMI percentile was associated with faster eating rates across all meals, greater fat mass index was only associated with faster eating at meals with portions typical for children (i.e., 100% and 133%). In a primarily healthy weight sample, an 'obesogenic' style of eating was a consistent predictor of greater intake across meals that varied in portion size. The consistent relationship of these behaviors with intake makes them promising targets to reduce overconsumption.

Spread it on thick? Relative effects of condiment addition and slice thickness on eating rate of bread

Manipulating eating rate (ER) by food properties may enhance or reduce food intake. Within composite foods, such as bread with condiments, the shape of carrier food and the use of condiments are known to influence ER. However, not much is known about their quantitative impacts and interactions. This study investigates the effect of bread slice thickness and addition of condiment on oral processing (ER, chews per g, bite size). In a full factorial design, 30 participants (BMI 21.6 ± 2.0 kg m-2, 23.3 ± 2.1 year) consumed two types of bread (wholewheat (WB); and sourdough (SB)), in three different slice thicknesses (1, 2, 4 cm), with three conditions of margarine addition (0, 2, 4 g per slice of 28 cm2). The results showed that addition of margarine in both breads led to ∼50% higher ER in a non-linear fashion mainly via less chews per g (all P < 0.001). Increasing bread slice thickness in both breads, resulted in ∼15% higher ER, mainly via larger bite sizes (all P < 0.001). The addition of margarine reduced or overruled the effect of slice thickness on all oral processing characteristics (interaction margarine × slice thickness, all P < 0.01). Perceived sensory dryness showed a strong negative correlation with ER. In conclusion, this study highlighted the importance of bread slice thickness, amount of a condiment, and their interactions in controlling ER. Lubrication of the dry crumbs was a main mechanism in controlling ER in this study. These insights can help the design of products with lower ER.

Does vaping affect the taste and smell perception? An exploratory study with New Zealand young adults

OBJECTIVE

The study aimed to assess potential effects of vaping on individual taste and smell perception in a sample of young adult New Zealanders.

DESIGN

This cross-sectional study measured taste and smell perception using intensity and hedonic ratings to two olfactory (i.e., vanillin, methional) and two gustatory stimuli (i.e., sucrose, monosodium glutamate), representing sweet and savoury flavours. Detection sensitivities to sucrose and vanillin were also assessed using a forced choice detection paradigm aligned with the signal detection framework. MANCOVAs were employed to compare sensory perception between groups based on vaping use frequency. Additional regression analyses were conducted to identify potential predictors of intensity and hedonic sensory ratings.

SETTING

Participants were recruited from the University of Otago student population and surrounding neighbourhoods of Dunedin, New Zealand in 2023.

PARTICIPANTS

The study included 213 university students (98 vapers and 115 non-vapers) RESULTS: We found a significant difference in hedonic ratings for vanillin, indicating a stronger preference among non-vapers. However, no other differences between the two groups were significant. Notably, the use of tobacco and mint flavours were emerged as significant predictors for hedonic responses to the savoury smell and sweet taste stimulus, respectively. No significant differences were observed between groups in the ability to detect weak stimuli.

CONCLUSIONS

Our findings suggest that vape use, particularly with specific flavours, may be associated with alterations in hedonic responses to smells. This finding may have potential implications for how vaping affects on food preferences and dietary choices.

Satiating Capacity of Plant-Based Meat in Realistic Meal Contexts at Home

Plant-based meat substitutes replacing animal meat can potentially support the transition towards more sustainable diets. To enable the required transition, consumer acceptance of plant-based meat is essential. An important aspect of this is the feeling of satiety or being full after eating. This study determined the satiating capacity of both plant-based meat and animal meat in 60 adults under real-life in-home conditions. Participants consumed four fixed ready-to eat meals for lunch at home once per week. Two types of Indian curry with 'chicken' were investigated as well as two types of pasta Bolognese with 'minced meat'. The two 'chicken' dishes and the two 'minced meat' dishes had the same recipe except for a gram-for-gram swap (125 g each) of either animal meat (chicken breast and minced meat) or plant-based (soy) meat. Results showed no difference in the satiating power of an animal meat dish and a plant-based meat dish when these were eaten as part of a full lunch meal at home. In addition, the meals did not result in energy nor macronutrient compensation during the rest of the day after consuming the meals. This occurred despite the caloric differences of the meals as a result of the real-life conditions (i.e., a lower energy content of the pasta with plant-based meat compared to the other meals). We conclude that meals with plant-based meat can be as satiating as meals with animal meat.

Speed limits: the effects of industrial food processing and food texture on daily energy intake and eating behaviour in healthy adults

PURPOSE

Frequent consumption of industrially processed foods has been associated with obesity. However, it is unknown what drives this association. Food textures of industrially processed foods that stimulate energy overconsumption may be an important driver of this association. Therefore, this study aimed to determine the independent and combined effects of food texture and level of industrial food processing (based on the NOVA classification) on daily energy intake and eating behaviour.

METHODS

Eighteen healthy adults (F/M: 11/7, 23 ± 3 y, 22.1 ± 2.0 kg/m2) participated in a 2 × 2 randomized crossover dietary intervention with four conditions (total of 288 meals): hard unprocessed, hard (ultra-)processed, soft unprocessed and soft (ultra-)processed. Daily diets were offered ad libitum and were equal in energy density (1 kcal/g). Food Intake (g) was measured by pre- and post-consumption weighing of the plates. Eating behaviour parameters were derived from video annotations.

RESULTS

Daily energy intake and food intake were, respectively, 33% (571 ± 135 kcal) and 14% (247 ± 146 g) lower in the hard compared to the soft conditions (main texture p < 0.001). Energy intake was lower in both hard conditions compared to the (ultra)processed soft condition (Tukey p < 0.04). Eating rate (g/min) was on average 85% slower (P < 0.001) in the hard compared to the soft conditions (p < 0.001). Level of processing did not affect food intake.

CONCLUSION

Consumption of hard-textured foods reduces daily energy intake of (ultra-) processed foods. This preliminary investigation shows that there is great variability in food properties that affect energy and food intake beyond industrial food processing. However, findings should be interpreted with precaution considering the limited sample size of this trial. Future classification systems for public health messaging should include energy intake rate to help reduce overconsumption.

CLINICAL TRIAL REGISTRY

NCT04280146, https://www.

CLINICALTRIALS

gov , February 21st 2020.

Apple versus chocolate: Evidence for discrimination of distension-related and calorie-related satiety signals in post-prandial fullness and hunger, and in the quality and location of other body sensations

Gastric distension and detection of macronutrients (calories) in the gut are determinants of satiation and satiety. We tested effects of these variables on body sensations after eating, and their connection with visual-analogue scale (VAS) hunger and fullness ratings. Participants completed VAS ratings and quality and location of body sensations tasks after consumption of milk chocolate (38 g, 200 kcal) versus fresh apple fruit matched for weight (38 g, 20 kcal) and matched for calories (380 g, 200 kcal). Effects of food weight (380 vs 38 g) were large and located predominantly in the abdominal region. They also occupied a greater body area and occurred sooner after eating than effects related to calories (200 vs 20 kcal). The same pattern was apparent in the results from the quality of sensations task. VAS ratings indicated that hunger was affected by food volume and calories, whereas fullness was affected primarily by food volume. Together, these results provide evidence of dissociation of the perceived after-effects of food ingestion related to food volume and food calorie content in humans. Additionally, the studies demonstrate the utility of two rarely used, semi-quantitative tasks, which generate information on the identity, intensity, valence, and location of eating-related sensations.

Metabolic Effects and Safety Aspects of Acute D-allulose and Erythritol Administration in Healthy Subjects

The rapid increase in sugar consumption is associated with various negative metabolic and inflammatory effects; therefore, alternative sweeteners become of interest. The aim of this study was to investigate the metabolic effects and safety aspects of acute D-allulose and erythritol on glucose, insulin, ghrelin, blood lipids, uric acid, and high-sensitive C-reactive protein (hsCRP). In three study visits, 18 healthy subjects received an intragastric administration of 25 g D-allulose or 50 g erythritol, or 300 mL tap water (placebo) in a randomized, double-blind and crossover order. To measure the aforementioned parameters, blood samples were drawn at fixed time intervals. Glucose and insulin concentrations were lower after D-allulose compared to tap water (p = 0.001, d_z = 0.91 and p = 0.005, d_z = 0.58, respectively); however, Bayesian models show no difference for insulin in response to D-allulose compared to tap water, and there was no effect after erythritol. An exploratory analysis showed that ghrelin concentrations were reduced after erythritol compared to tap water (p = 0.026, d_z = 0.59), with no effect after D-allulose; in addition, both sweeteners had no effect on blood lipids, uric acid and hsCRP. This combination of properties identifies both sweeteners as excellent candidates for effective and safe sugar alternatives.

Eating rate and bite size were related to food intake across meals varying in portion size: A randomized crossover trial in adults

Serving larger portions leads to increased food intake, but behavioral factors that influence the magnitude of this portion size effect have not been well characterized. We investigated whether measures of eating microstructure such as eating rate and bite size moderated the portion size effect. We also explored how sensory-specific satiety (SSS; the relative hedonic decline of a food as it is eaten) was affected by eating microstructure and larger portions. In a randomized crossover design, 44 adults aged 18-68 y (66% women; 46% with overweight and obesity) ate lunch in the laboratory once a week for 4 weeks. The meal consisted of pasta that was varied in portion size (400, 500, 600, or 700 g) and 700 g of water. Meals were video-recorded to assess bite count and meal duration, which were used to calculate mean eating rate (g/min) and mean bite size (g/bite). At each meal participants also completed an assessment of SSS. The results showed that as larger portions were served, meal intake increased in a curvilinear manner (p < 0.0001). Measures of eating microstructure did not moderate the portion size effect but were related to intake across all portions; faster eating rate, larger bite size, higher bite count, and longer meal duration were associated with greater consumption at all meals (all p < 0.0001). SSS was not influenced by any measure of eating microstructure or by portion size (all p > 0.10). In summary, the portion size effect was not moderated by eating microstructure, but relatively faster eating rates and larger bite sizes at meals, along with large portions, combined to increase food intake.

Dissecting ultra-processed foods and drinks: Do they have a potential to impact the brain?

Ultra-processed foods and drinks (UPF) are formulation of ingredients, mostly of exclusive industrial use, that result from a series of industrial processes. They usually have a low nutrient but high energy density, with a high content of saturated and trans fats, and added sugars. In addition, they have characteristic organoleptic properties, and usually contain sophisticated additives, including artificial sweeteners, to intensify their sensory qualities and imitate the appearance of minimally processed foods. In addition, recent research has warned about the presence of chemicals (e.g., bisphenol) and neo-formed contaminants in these products. UPF production and consumption growth have been spectacular in the last decades, being specially consumed in children and adolescents. UPF features have been associated with a range of adverse health effects such as overeating, the promotion of inflammatory and oxidative stress processes, gut dysbiosis, and metabolic dysfunction including problems in glucose regulation. The evidence that these UPF-related adverse health effects may have on the neural network implicated in eating behavior are discussed, including the potential impact on serotonergic and dopaminergic neurotransmission, brain integrity and function. We end this review by placing UPF in the context of current food environments, by suggesting that an increased exposure to these products through different channels, such as marketing, may contribute to the automatic recruitment of the brain regions associated with food consumption and choice, with a detrimental effect on inhibitory-related prefrontal cortices. While further research is essential, preliminary evidence point to UPF consumption as a potential detrimental factor for brain health and eating behavior.

The Importance of Food Processing and Eating Behavior in Promoting Healthy and Sustainable Diets

Numerous association studies and findings from a controlled feeding trial have led to the suggestion that "processed" foods are bad for health. Processing technologies and food formulation are essential for food preservation and provide access to safe, nutritious, affordable, appealing and sustainable foods for millions globally. However, food processing at any level can also cause negative health consequences that result from thermal destruction of vitamins; formation of toxins such as acrylamide; or excessive intakes of salt, sugar, and fat. Research on ultraprocessed foods centers on food composition and formulation. In addition, many modern food formulations can have poor nutritional quality and higher energy density. We outline the role of processing in the provision of a safe and secure food supply and explore the characteristics of processed foods that promote greater energy intake. Despite the potential for negative health effects, food processing and formulation represent an opportunity to apply the latest developments in technology and ingredient innovation to improve the food supply by creating foods that decrease the risk of overeating. Expected final online publication date for the Annual Review of Nutrition, Volume 42 is August 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Interrelations Between Food Form, Texture, and Matrix Influence Energy Intake and Metabolic Responses

Purpose of Review

Nutrition often focuses on food composition, yet differences in food form, texture, and matrix influence energy intake and metabolism. This review outlines how these attributes of food impact oral processing, energy intake, and metabolism.

Recent Findings

Food form has a well-established impact on intake, where liquids are consumed more than solids and semi-solids. For solids, texture properties like thickness, hardness, and lubrication, and geometrical properties like size and shape influence oral processing, eating rate, and intake. Food matrix integrity can influence nutrient and energy absorption and is strongly influenced by food processing.

Summary

Food texture and matrix play important roles in modulating energy intake and absorption. Future research needs to consider the often overlooked role of texture and matrix effects on energy and metabolic responses to composite foods and meals. Research is needed to understand how processing impacts macro- and micro-structure of food and its long-term impact on energy balance and health.

Appetite and Satiety Control-Contribution of Gut Mechanisms

The prevalence of obesity, and its comorbidities, particularly type 2 diabetes, cardiovascular and hepatic disease and certain cancers, continues to rise at an alarming rate worldwide [...].