Rate-induced tipping in complex high-dimensional ecological networks.

In an ecosystem, environmental changes as a result of natural and human processes can cause some key parameters of the system to change with time. Depending on how fast such a parameter changes, a tipping point can occur. Existing works on rate-induced tipping, or R-tipping, offered a theoretical way to study this phenomenon but from a local dynamical point of view, revealing, e.g., the existence of a critical rate for some specific initial condition above which a tipping point will occur. As ecosystems are subject to constant disturbances and can drift away from their equilibrium point, it is necessary to study R-tipping from a global perspective in terms of the initial conditions in the entire relevant phase space region. In particular, we introduce the notion of the probability of R-tipping defined for initial conditions taken from the whole relevant phase space. Using a number of real-world, complex mutualistic networks as a paradigm, we find a scaling law between this probability and the rate of parameter change and provide a geometric theory to explain the law. The real-world implication is that even a slow parameter change can lead to a system collapse with catastrophic consequences. In fact, to mitigate the environmental changes by merely slowing down the parameter drift may not always be effective: Only when the rate of parameter change is reduced to practically zero would the tipping be avoided. Our global dynamics approach offers a more complete and physically meaningful way to understand the important phenomenon of R-tipping.

Adaptable reservoir computing: A paradigm for model-free data-driven prediction of critical transitions in nonlinear dynamical systems.

A problem in nonlinear and complex dynamical systems with broad applications is forecasting the occurrence of a critical transition based solely on data without knowledge about the system equations. When such a transition leads to system collapse, as often is the case, all the available data are from the pre-critical regime where the system still functions normally, making the prediction problem challenging. In recent years, a machine-learning based approach tailored to solving this difficult prediction problem, adaptable reservoir computing, has been articulated. This Perspective introduces the basics of this machine-learning scheme and describes representative results. The general setting is that the system dynamics live on a normal attractor with oscillatory dynamics at the present time and, as a bifurcation parameter changes into the future, a critical transition can occur after which the system switches to a completely different attractor, signifying system collapse. To predict a critical transition, it is essential that the reservoir computer not only learns the dynamical "climate" of the system of interest at some specific parameter value but, more importantly, discovers how the system dynamics changes with the bifurcation parameter. It is demonstrated that this capability can be endowed into the machine through a training process with time series from a small number of distinct, pre-critical parameter values, thereby enabling accurate and reliable prediction of the catastrophic critical transition. Three applications are presented: predicting crisis, forecasting amplitude death, and creating digital twins of nonlinear dynamical systems. Limitations and future perspectives are discussed.

Interventions to promote healthy lifestyle behaviors in children and adolescents in summer day camps: a scoping review.

BACKGROUND: Children and adolescents have suboptimal physical activity and eating habits during summer breaks. Unlike the school setting, there is little evidence on interventions to promote healthy lifestyle behaviors in Summer Day Camps (SDCs). METHODS: The aim of this scoping review was to examine physical activity, healthy eating, and sedentary behavior interventions in the SDCs. A systematic search on four platforms (EBSCOhost, MEDLINE, EMBASE, and Web of Science) was performed in May 2021 and was updated in June 2022. Studies related to promoting healthy behaviors, physical activity, sedentary behaviors and/or healthy eating among campers aged 6 to 16 in Summer Day Camps were retained. The protocol and writing of the scoping review were done according to the guidelines of the "Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for scoping reviews (PRISMA-ScR)". RESULTS: Most interventions had a positive effect on the behavioral determinants or the behaviors themselves (i.e., physical activity, sedentary behaviors, or healthy eating). Involving counsellors and parents, setting camp goals, gardening, and education are all relevant strategies in promoting healthy lifestyle behaviors in SDCs. CONCLUSIONS: Since only one intervention directly targeted sedentary behaviors, it should strongly be considered for inclusion in future studies. In addition, more long-term and experimental studies are needed to establish cause-and-effect relationships between healthy behavior interventions in SDCs and behaviors of children and young adolescents.

Eating behaviour traits mediate the association between satiety responsiveness and energy intake among individuals with overweight and obesity.

Whether eating behaviour traits represent factors that could explain the susceptibility to overeating in individuals with low satiety responsiveness remain to be extensively examined. This study aimed to assess if eating behaviours mediate the association between satiety responsiveness and energy intake. Baseline data from individuals with overweight or obesity (n = 303; age = 38.7 ± 8.4 years; BMI = 33.2 ± 3.4 kg/m2, 56% women) who participated in four weight-loss studies were included in this cross-sectional study. Satiety responsiveness was determined by the satiety quotient (SQ) based on fullness sensations in response to a standardized breakfast. Energy intake was self-reported in a three-day food record and measured by an ad libitum buffet meal. Eating behaviours were assessed with questionnaires. Mediation analyses adjusted for age and sex, and for underreporting for the food record, were performed using a regression-based and bootstrapping approach. The association between SQ and self-reported total energy intake was mediated by susceptibility to hunger (ß = -2.51 ± 1.26, 95% CI, -5.38 to -0.52) and its subscales, internal and external locus of hunger (ß = -2.00 ± 1.10, 95% CI, -4.50 to -0.28 and ß = -2.42 ± 1.29, 95% CI, -5.30 to -0.30, respectively). Susceptibility to hunger (ß = -2.71 ± 1.13, 95% CI, -5.29 to -0.84), internal and external locus of hunger (ß = -1.84 ± 0.95, 95% CI -4.00 to -0.30 and ß = -3.42 ± 1.31, 95% CI, -6.39 to -1.24, respectively), cues that may trigger food cravings (ß = -5.43 ± 2.91, 95% CI, -11.83 to -0.44) and state-craving as a physiological state (ß = -4.31 ± 2.51, 95%CI, -10.14 to -0.44) also mediated the association between SQ and measured energy intake. These results suggest that susceptibility to hunger and food cravings partly explained the susceptibility to overeating among individuals with low satiety responsiveness. Interventions targeting susceptibility to hunger and food cravings may thus be helpful to prevent overeating among these individuals.

The impact of a family web-based nutrition intervention to increase fruit, vegetable, and dairy intakes: a single-blinded randomized family clustered intervention.

BACKGROUND: The importance of adopting healthy eating habits at a young age to prevent obesity and chronic diseases justifies the need for effective interventions. OBJECTIVE: This study evaluated the impact of a family web-based nutrition intervention on vegetable and fruit (V/F) and dairy product (DP) consumption, nutrient intakes, diet quality and BMI or BMI z-scores. METHODS: Forty-three families with children aged 8-16 years were randomized to either the family web-based intervention, or web-based general nutrition guidelines (control) over 8 weeks. Nutritional variables were assessed with three-day dietary records while anthropometry (body weight and height) was assessed with standardized measures at baseline (PRE), immediately after the intervention (POST 1) and 3-6 months after the intervention (POST 2). Linear mixed models for repeated measures were used to assess the main effects and their interactions followed by post hoc tests. RESULTS: The intervention had an effect on DP, total sugar, potassium, magnesium, and calcium in children (Group x Time, P = 0.02 to 0.03) and on DP, V/F juice, carbohydrates, total sugar, saturated fat, protein and calcium in parents (Group x Time, P = 0.01 to 0.03). Post hoc tests revealed children in the intervention group increased their DP intakes immediately after the intervention (POST1) but decreased at follow-up (POST2). No effect of the intervention on V/F, diet quality or BMI was observed. CONCLUSION: Compared to general nutrition guidelines, this family web-based nutrition intervention had a modest effect on nutrient intakes, but beneficial effect on DP intakes in the short term. TRIAL REGISTRATION: ClinicalTrials.gov , NCT03798808 , Registered 10 january 2019 - Retrospectively registered.

Translation and validation of the Child Three-Factor Eating Questionnaire (CTFEQr17) in French-speaking Canadian children and adolescents.

OBJECTIVE: To translate and validate the Child Three-Factor Eating Questionnaire (CTFEQr17), assessing cognitive restraint (CR), uncontrolled eating (UE) and emotional eating (EE), among French-speaking Canadian young individuals. DESIGN: Phase 1 comprised a translation and the evaluation of the comprehension of the questionnaire. Phase 2 comprised a confirmatory factor analysis (CFA), the evaluation of internal consistency (Cronbach's α), test-retest reliability (intra-class correlation coefficients (ICC)) and construct validity, including correlations among the CTFEQr17 and Eating Attitudes Test (EAT-26), anthropometrics, dietary intake and diet quality. SETTING: Primary and secondary schools, Québec City, Canada. PARTICIPANTS: Phases 1 and 2 included 20 (40 % boys, mean age 11·5 (sd 2·4) years) and 145 (48 % boys, mean age 11·0 (sd 1·9) years) participants, respectively. RESULTS: Phase 1 resulted in the questionnaire to be used in Phase 2. In Phase 2, the CFA revealed that the seventeen item, three-factor model (CTFEQr17) provided an excellent fit. Internal consistency was good (Cronbach's α: 0·81-0·90). Test-retest reliability was moderate to good (ICC = 0·59, (95 % CI 0·48, 0·70), ICC = 0·78, (95 % CI 0·70, 0·84), ICC = 0·50, (95 % CI 0·38, 0·62) for CR, UE and EE, respectively). CR correlated with EAT-26 score (r = 0·43, P < 0·0001). UE and EE correlated negatively with BMI Z-scores (r = -0;·26, P = 0·003; r = -0;·19, P = 0·03, respectively). CR correlated with the proportion of energy intake from protein and diet quality (r = 0·18, P = 0·04; r = 0·20, P = 0·02, respectively). CONCLUSION: The CTFEQr17 is suitable to use among French-speaking Canadian young individuals.

Pinning control of networks: Dimensionality reduction through simultaneous block-diagonalization of matrices.

In this paper, we study the network pinning control problem in the presence of two different types of coupling: (i) node-to-node coupling among the network nodes and (ii) input-to-node coupling from the source node to the "pinned nodes." Previous work has mainly focused on the case that (i) and (ii) are of the same type. We decouple the stability analysis of the target synchronous solution into subproblems of the lowest dimension by using the techniques of simultaneous block diagonalization of matrices. Interestingly, we obtain two different types of blocks, driven and undriven. The overall dimension of the driven blocks is equal to the dimension of an appropriately defined controllable subspace, while all the remaining undriven blocks are scalar. Our main result is a decomposition of the stability problem into four independent sets of equations, which we call quotient controllable, quotient uncontrollable, redundant controllable, and redundant uncontrollable. Our analysis shows that the number and location of the pinned nodes affect the number and the dimension of each set of equations. We also observe that in a large variety of complex networks, the stability of the target synchronous solution is de facto only determined by a single quotient controllable block.

Matryoshka and disjoint cluster synchronization of networks.

The main motivation for this paper is to characterize network synchronizability for the case of cluster synchronization (CS), in an analogous fashion to Barahona and Pecora [Phys. Rev. Lett. 89, 054101 (2002)] for the case of complete synchronization. We find this problem to be substantially more complex than the original one. We distinguish between the two cases of networks with intertwined clusters and no intertwined clusters and between the two cases that the master stability function is negative either in a bounded range or in an unbounded range of its argument. Our proposed definition of cluster synchronizability is based on the synchronizability of each individual cluster within a network. We then attempt to generalize this definition to the entire network. For CS, the synchronous solution for each cluster may be stable, independent of the stability of the other clusters, which results in possibly different ranges in which each cluster synchronizes (isolated CS). For each pair of clusters, we distinguish between three different cases: Matryoshka cluster synchronization (when the range of the stability of the synchronous solution for one cluster is included in that of the other cluster), partially disjoint cluster synchronization (when the ranges of stability of the synchronous solutions partially overlap), and complete disjoint cluster synchronization (when the ranges of stability of the synchronous solutions do not overlap).

Validation of the Adult Eating Behaviour Questionnaire adapted for the French-speaking Canadian population.

PURPOSE: The Adult Eating Behaviour Questionnaire (AEBQ) is a newly developed questionnaire adapted from the widely used Child Eating Behaviour Questionnaire. This questionnaire assesses four food approach scales, namely hunger, food responsiveness, emotional overeating (EOE) and enjoyment of food, and four food avoidance scales, namely satiety responsiveness (SR), emotional undereating (EUE), food fussiness and slowness in eating (SE). This study aimed to validate a French version of the AEBQ in controlled conditions among French-speaking adults from Quebec, Canada. METHODS: The AEBQ was pre-tested through structured interviews with 30 individuals. Participants of the validation study (n = 197, aged 19-65 years) had their height and weight measured and completed the AEBQ, Three-Factor Eating Questionnaire (TFEQ) and Intuitive Eating Scale-2 to assess factorial structure, internal consistency and construct validity. Test-retest reliability over 2 weeks was assessed among 144 participants. RESULTS: Confirmatory factor analysis indicated an excellent model fit (NNFI = 0.98, CFI = 0.98, RMSEA = 0.03, χ2/df = 1.17) and provided support for the use of the original 8-factor questionnaire. Internal consistency was adequate for most scales (Cronbach's alpha = 0.66-0.94) and moderate to excellent test-retest reliability was observed for all scales (ICC = 0.70-90). Women showed higher levels of EOE and SR, and individuals with overweight and obesity showed higher levels of EOE and lower levels of EUE and SE. Construct validity was also supported by expected correlations with disinhibition and susceptibility to hunger from the TFEQ and intuitive eating. CONCLUSION: This study indicates that the French AEBQ is a valid and reliable tool to measure eating behaviours in the adult population of Quebec. LEVEL OF EVIDENCE: Level III: Evidence obtained from well-designed cohort or case-control analytic studies. The data are cross-sectional, but all measurement were undertaken in controlled laboratory conditions and the study provided new information.

Cluster synchronization of networks via a canonical transformation for simultaneous block diagonalization of matrices.

We study cluster synchronization of networks and propose a canonical transformation for simultaneous block diagonalization of matrices that we use to analyze the stability of the cluster synchronous solution. Our approach has several advantages as it allows us to: (1) decouple the stability problem into subproblems of minimal dimensionality while preserving physically meaningful information, (2) study stability of both orbital and equitable partitions of the network nodes, and (3) obtain a parameterization of the problem in a small number of parameters. For the last point, we show how the canonical transformation decouples the problem into blocks that preserve key physical properties of the original system. We also apply our proposed algorithm to analyze several real networks of interest, and we find that it runs faster than alternative algorithms from the literature.

Yogurt consumption, body composition, and metabolic health in the Québec Family Study.

PURPOSE: The aim was to compare the anthropometric and metabolic profiles and lifestyle behaviours of yogurt consumers and non-consumers and to determine if the observed differences persisted after adjustment for diet quality and related variables. METHODS: Using cross-sectional and follow-up data from the Québec Family Study, men and women were classified into yogurt consumers (n = 269; 96 men and 173 women) and non-consumers (n = 570; 279 men and 291 women), and their anthropometric measurements, metabolic profiles, and lifestyle factors were compared. RESULTS: Men yogurt consumers had a lower body weight, BMI, % body fat, waist circumference and lower plasma insulin, and C-peptide concentrations in response to oral glucose, while women yogurt consumers had lower waist circumference, BMI, % body fat, plasma glucose, insulin, and C-peptide compared with non-consumers (P < 0.05). After adjustment for the Nutrient-Rich Foods (NRF) index, a marker of diet quality, these differences persisted in men and only for glycemic variables in women. Additional adjustment for physical activity participation and % body fat did not abolish the significant differences observed between yogurt consumers and non-consumers for plasma glucose, insulin, and C-peptide responses to oral glucose in women only (P < 0.05). Analyses of data after a 6-year follow-up reinforced these observations, since both men and women yogurt consumers maintained a better metabolic profile compared with non-consumers after adjustments for age and NRF (P < 0.05). In addition, an interaction between group and time for % body fat in men suggests a benefit of yogurt consumption over time on body composition. CONCLUSION: Yogurt consumption is associated with body composition and metabolic health benefits that are not entirely explained by a global effect of diet quality.

A New Chaotic System with a Self-Excited Attractor: Entropy Measurement, Signal Encryption, and Parameter Estimation.

In this paper, we introduce a new chaotic system that is used for an engineering application of the signal encryption. It has some interesting features, and its successful implementation and manufacturing were performed via a real circuit as a random number generator. In addition, we provide a parameter estimation method to extract chaotic model parameters from the real data of the chaotic circuit. The parameter estimation method is based on the attractor distribution modeling in the state space, which is compatible with the chaotic system characteristics. Here, a Gaussian mixture model (GMM) is used as a main part of cost function computations in the parameter estimation method. To optimize the cost function, we also apply two recent efficient optimization methods: WOA (Whale Optimization Algorithm), and MVO (Multi-Verse Optimizer) algorithms. The results show the success of the parameter estimation procedure.

Yogurt Consumption as a Signature of a Healthy Diet and Lifestyle.

Yogurt is considered to be a nutrient-dense food that significantly contributes to the intake of several nutrients, including calcium and protein. As described in this paper, yogurt consumers have a higher nutrient intake than do nonconsumers. Yogurt consumers are also characterized by healthier dietary habits than nonconsumers, which partly explains their reduced incidence of overweight and obesity. Recent studies also suggest that yogurt consumers exhibit healthier nonnutritional behaviors, such as reduced smoking and greater participation in physical activity, than do nonconsumers. Furthermore, when greenhouse gas emissions are used as an additional criterion to categorize foods, yogurt appears to be an eco-friendly food. Compared with that of other foods, the carbon footprint of yogurt production is low to moderate and may be included as part of a healthy and sustainable diet. Based on these factors, yogurt consumption may be the signature of a healthy diet and lifestyle.

The impact of an innovative web-based school nutrition intervention to increase fruits and vegetables and milk and alternatives in adolescents: a clustered randomized trial.

BACKGROUND: The increase in overweight and obesity in adolescents and its health-related consequences highlight the need to develop strategies, which could help them adopt healthy eating habits. The objective of this study was to evaluate the impact of an innovative web-based school nutrition intervention (Team Nutriathlon) aimed at promoting the consumption of vegetables and fruit (V/F) and milk and alternatives (M/A) in high school students and to identify facilitators and/or barriers influencing its success. METHODS: Ten classes of first and second year secondary students (grades 7 and 8) from the Québec City region were randomized into two groups (control n = 89 and intervention n = 193). Participants in the intervention (Team Nutriathlon) were to increase their consumption of V/F and M/A using an innovative web-based platform, developed for this study, over 6 weeks. The control group followed the regular school curriculum. The number of servings of V/F and M/A consumed by students per day was compared between the two groups before, during, immediately after and 10 weeks after the intervention using a web-based platform. Main outcome measures included V/F and M/A servings and facilitators and/or barriers of program success. Repeated measures linear fixed effects models were used to assess the impact of Team Nutriathlon on V/F and M/A consumption. A P-value of <0.05 was considered significant. RESULTS: Students in the intervention reported a significant increase of 3 servings and 1.8 servings per day of V/F and M/A, respectively, compared to the control group (P < 0.05); however, this was only observed in the short-term. Some factors contributing to the success of Team Nutriathlon included the team aspect of the program, use of the technology and recording results outside of classroom hours. CONCLUSION: Team Nutriathlon represents an innovative web-based nutrition program which positively impacts V/F and M/A consumption among high school students. Using web-based or technological platforms may help youth adopt healthy eating habits that will have implications later in adulthood; however, further studies are needed to determine their long-term effects. TRIAL REGISTRATION: NCT03117374 (retrospectively registered).

The Potential Role of Yogurt in Weight Management and Prevention of Type 2 Diabetes.

Yogurt is a semisolid fermented milk product that originated centuries ago and is viewed as an essential food and important source of nutrients in the diet of humans. Over the last 30 years, overweight and obesity have become characteristic of Western and developing countries, which has led to deleterious health outcomes, including cardiovascular disease, type 2 diabetes, hypertension, and other chronic conditions. Recent epidemiological and clinical evidence suggests that yogurt is involved in the control of body weight and energy homeostasis and may play a role in reducing the risk for type 2 diabetes partly via the replacement of less healthy foods in the diet, its food matrix, the effect of specific nutrients such as calcium and protein on appetite control and glycemia, and alteration in gut microbiota. This review will discuss the specific properties that make yogurt a unique food among the dairy products, epidemiological and clinical evidence supporting yogurt's role in body weight, energy balance, and type 2 diabetes, including its potential mechanisms of action and gaps that need to be explored. Key teaching points • Several epidemiological and clinical studies have suggested a beneficial effect of yogurt consumption in the control of body weight and energy homeostasis, although this remains controversial. • Yogurt possesses unique properties, including its nutritional composition; lactic acid bacteria, which may affect gut microbiota; and food matrix, which may have a potential role in appetite and glycemic control. • Potential mechanisms of action of yogurt include an increase in body fat loss, decrease in food intake and increase in satiety, decrease in glycemic and insulin response, altered gut hormone response, replacement of less healthy foods, and altered gut microbiota. • The relative energy and nutrient content and contribution of a standard portion of yogurt to the overall diet suggest that the percentage daily intake of these nutrients largely contributes to nutrient requirements and provides a strong contribution to the regulation of energy metabolism.

Canned Navy Bean Consumption Reduces Metabolic Risk Factors Associated with Obesity.

The high prevalence of obesity and its metabolic co-morbidities require dietitians to promote lifestyle modifications that can be effectively implemented into practice and are feasible for customers to adhere to. The objective of this study was to determine the effect of commercially available ready-to-eat canned navy beans added to the habitual diet on risk factors associated with obesity. Fourteen overweight and obese adults consumed 5 cups of canned navy beans per week for 4 weeks. The study results demonstrated that bean consumption results in reduced waist circumference in females by 2.5 cm and males by 2.1 cm (P < 0.001). The effect of beans on pulse rate, total cholesterol (TC), and low-density lipoprotein cholesterol (LDL) were sex dependent (P < 0.05). In males, pulse rate, TC, and LDL were decreased by 6.5%, 11.5%, and 18%, respectively. In females, pulse rate increased by 9.6%, and TC and LDL were relatively unchanged. There was a trend for a decreased glucose AUC (P = 0.06) in response to a glucose load. This study demonstrates that consuming 5 cups per week of ready-to-eat canned navy beans for 4 weeks reduces metabolic risk factors associated with obesity and therefore can be used as a tool in dietetic practice.

Glycemic effect of oat and barley beta-glucan when incorporated into a snack bar: a dose escalation study.

BACKGROUND: The blood glucose-lowering effects of ß-glucan from oats and barley depend on the amounts consumed and their rheological properties. This has been recently challenged with growing evidence that the food matrix may also be an important factor in predicting its physiological response. OBJECTIVE: The objective of this study was to examine the effects of varying doses of ß-glucan from oats and barley and added to a snack bar on postprandial glycemia. DESIGN: In a randomized crossover study, 12 healthy males and females consumed one of 8 snack bars containing 0 (control), 1.5, 3, and 6 g of ß-glucan derived from oats or barley or 3 white bread controls. All treatments contained 50 g of available carbohydrate. Blood glucose concentrations were measured after ingestion of the treatments over 2 hours. RESULTS: Incorporation of 1.5 to 6 g of ß-glucan into snack bars had no additional glucose-lowering benefits irrespective of dose and source compared to the control bars (0 g ß-glucan), suggesting that both the solid food matrix and composition of the bars may play a role in their effects on glycemic response. All bars reduced blood glucose area under the curve (AUC) by an average of 25% (p < 0.05) compared to the mean of the 3 white bread controls. CONCLUSION: Adding ß-glucan from oats and barley to the snack bar formulation used in this study did not yield any additional benefits beyond the glucose-lowering effects of the snack bars themselves.

Overcoming Barriers in Eating Disorder Care: Advances, Gaps, and Recommendations for Equitable Assessment and Treatment.

This paper provides an overview of topics discussed by clinicians and researchers invited to speak at the Canadian Nutrition Society's Thematic Conference 2023, which was centered on advances in research and practice in the assessment and treatment of disordered eating and eating disorders. Presenters emphasized the importance of understanding how systemic factors such as racism, weight stigma, and COVID-19 affect the assessment and treatment of eating disorders, and proposed strategies for addressing these inequities. In this paper, we provide actionable recommendations for clinicians working with individuals with eating disorders; professional development, cultural competence, and equitable assessment and treatment practices are discussed.

Caloric beverages consumed freely at meal-time add calories to an ad libitum meal.

The objective was to compare the effects of ad libitum consumption of commonly consumed meal-time beverages on energy and fluid intakes and post-meal average subjective appetite and blood glucose in healthy adults. In a randomized controlled design, 29 males and females consumed to satiation an ad libitum pizza meal with one of five beverages in unlimited amount including water (0 kcal), 1% milk (44 kcal/100 ml), regular cola (44 kcal/100 ml), orange juice (44 kcal/100 ml) and diet cola (0 kcal). Food and fluid intakes were measured at the meal. Average subjective appetite and blood glucose were measured before and for 2h after the meal. Although energy intake from pizza was similar among all beverage treatments, the amount of fluid consumed (g) varied among the beverages with intake of orange juice higher than regular and diet cola, but not different from water or milk. Meal-time ingestion of caloric beverages, milk, orange juice and regular cola, led to higher total meal-time energy intakes compared to either water or diet cola. Post-meal blood glucose area under the curve (AUC) was lower after milk than after meals with water, orange juice and regular cola and post-meal average subjective appetite AUC was lower after milk than after meals with water. Meal intakes of nutrients including protein, calcium, phosphorus, zinc, vitamins B12, A and D were higher at the meal with milk compared to the other beverages. Thus, caloric beverages consumed ad libitum during a meal add to total meal-time energy intake, but 1% milk favors a lower post-meal blood glucose and average subjective appetite score and adds to nutrient intake.

Energy and macronutrient content of familiar beverages interact with pre-meal intervals to determine later food intake, appetite and glycemic response in young adults.

The objective was to compare the effects of pre-meal consumption of familiar beverages on appetite, food intake, and glycemic response in healthy young adults. Two short-term experiments compared the effect of consumption at 30 (experiment 1) or 120 min (experiment 2) before a pizza meal of isovolumetric amounts (500 mL) of water (0 kcal), soy beverage (200 kcal), 2% milk (260 kcal), 1% chocolate milk (340 kcal), orange juice (229 kcal) and cow's milk-based infant formula (368 kcal) on food intake and subjective appetite and blood glucose before and after a meal. Pre-meal ingestion of chocolate milk and infant formula reduced food intake compared to water at 30 min, however, beverage type did not affect food intake at 2h. Pre-meal blood glucose was higher after chocolate milk than other caloric beverages from 0 to 30 min (experiment 1), and after chocolate milk and orange juice from 0 to 120 min (experiment 2). Only milk reduced post-meal blood glucose in both experiments, suggesting that its effects were independent of meal-time energy intake. Combined pre- and post-meal blood glucose was lower after milk compared to chocolate milk and orange juice, but did not differ from other beverages. Thus, beverage calorie content and inter-meal intervals are primary determinants of food intake in the short-term, but macronutrient composition, especially protein content and composition, may play the greater role in glycemic control.