Search Results (45)

Low glycemic-index foods may reduce postprandial oxidative stress by reducing postprandial glucose excursions, but the evidence for this is limited by dietary confounders. To determine whether reducing postprandial glucose per se reduces postprandial oxidative stress, overnight-fasted participants (BMI 25.0–39.9 kg/m², n = 18) consumed four test meals in random order: 75 g dextrose solution (Dex) within 5 min (bolus/noC), Dex slowly over 3.25 h (sipping/noC), bolus with 1 g vitamin C (bolus/C) and sipping with 1 g vitamin C (sipping/C). Venous blood was taken at intervals over 6 h; a standard lunch was consumed at 4 h. Sipping flattened postprandial glucose and insulin and reduced free fatty acid rebound compared to bolus (p < 0.05). Vitamin C raised serum vitamin C from ~20 to ~55 μmol/L. The total peroxyl radical trapping antioxidant potential (TRAP) increments differed after lunch, with a main effect of vitamin C at 5 h (mean ± SEM; C 70 ± 23 vs. noC −29 ± 27; p = 0.016) and main effects of rate (sipping 57 ± 25 vs. bolus −71 ± 28; p = 0.0002) and vitamin C (C 58 ± 25 vs. noC −73 ± 28; p = 0.0003) at 6 h. By multiple regression analysis, the TRAP area under the curve (AUC) was positively associated with the insulin AUC (p < 0.001) and negatively with the glucose and vitamin C AUCs (p < 0.05). The oxidized LDL increments were higher 6 h after sipping than bolus (7 ± 7 vs. −20 ± 7, p = 0.005). The oxidized LDL AUC was negatively associated with the TRAP AUC (p < 0.001). These results support the hypothesis that reducing postprandial glucose reduces postprandial oxidative stress. Full article

Background/Objectives: School meals play an important role in ensuring reliable, healthy access to food, but there are many barriers to participation, especially for rural students. This study examined the perceived impact of UFSM policies and the perceptions of school meals among students in rural areas of Maine. Methods: This mixed-methods study included surveys with n = 61 middle and high school students and interviews with n = 11 middle and high school students between 2023 and 2024. The surveys and interviews focused on potential impacts of UFSM policies as well as general barriers and facilitators to participation in school meals. Quantitative surveys were analyzed using logistic regression, adjusting for demographic characteristics. Interviews were analyzed using principles of content analysis. Results: Students reported that UFSM had multiple benefits, and many students perceived that providing free school meals for all helped reduce the stigma associated with school meals, in part through increased participation. Students liked the variety of foods offered, but many did not perceive school meals, especially breakfast, to be “fresh” or “healthy”. Additionally, many students perceived there to be long lunch lines and insufficient time to eat their meals. Conclusions: While students perceived multiple benefits to UFSM, opportunities to further improve the quality of school meals, as well as policies to ensure sufficient lunch period lengths, may be important complements to increase participation and consumption of school meals among rural students. Full article

School meals are a cornerstone of the United States’ nutrition safety net for children from low-income families, providing nearly 30 million lunches daily. However, recent U.S. policy actions may limit access to school meals for children who need them most. The One Big Beautiful Bill Act changed eligibility requirements to limit participation in the Supplemental Nutrition Assistance Program (SNAP) and Medicaid. School-age children enrolled in SNAP and Medicaid are automatically enrolled in school meal programs. Limiting participation in SNAP and Medicaid has the potential to significantly impact children’s ability to receive nutritious school meals at low or no cost, will make it harder for schools to participate in community eligibility provision, and will increase the administrative burden on school staff and parents. Full article

Background: The Healthy, Hunger-Free Kids Act requires access to free drinking water in public school cafeterias during meal times. Previous studies suggest that increasing access to water in schools can increase its consumption among students, potentially reducing their intake of sugar-sweetened beverages. The current study provides a descriptive assessment of water availability, delivery methods, and quality in 96 public schools across four New Jersey school districts. Methods: As part of the New Jersey Child Health Study, we administered an online and paper survey to school nurses at 96 schools to evaluate the availability, delivery, and quality of water in the school cafeteria during lunchtime. Univariate and bivariate statistics were used to analyze the data. Results: In school year 2019–20, 83 (86.5%) schools reported providing free drinking water in the cafeteria during lunch. The most common source of water was water fountains, available in 64 schools (66.7%). Issues related to water quality, specifically cleanliness, temperature, pressure, and taste, were present in 20–30% of schools. Conclusions: While most schools surveyed provide access to clean, free drinking water, students in some schools still lack free access to drinking water during school meals, which may affect overall water consumption among students. Full article

Distribution systems’ vulnerability to power losses remains high, among other parts of the power system, due to the high currents and lower voltage ratio. Connecting distributed generation (DG) units can reduce power loss and improve the overall performance of the distribution networks if sized and located correctly. However, existing studies have usually assumed that DGs operate only at the unity power factor (i.e., type-I DGs) and ignored their dynamic capability to control reactive power, which is unrealistic when optimizing DG allocation in power distribution networks. In contrast, optimizing the allocation of DG units injecting reactive power (type-II), injecting both active and reactive powers (type-III), and injecting active power and dynamically adjusting (absorbing or injecting) reactive power (type-IV) is a more likely approach, which remains unexplored in the current literature. Additionally, various metaheuristic optimization techniques are employed in the literature to optimally allocate DGs in distribution networks. However, the no-free-lunch theorem emphasizes employing novel optimization approaches, as no method is best for all optimization problems. This study demonstrates the potential of optimally allocating different DG types simultaneously to improve power distribution network performance using a parameter-free Jaya optimization technique. The primary objective of optimally allocating DG units is minimizing the distribution network’s power losses. The simulation validation of this study is conducted using the IEEE 33-bus test system. The results revealed that optimally allocating a multiunit DG mix instead of a single DG type significantly reduces power losses. The highest reduction of 96.14% in active power loss was obtained by placing three type-II, two type-III, and three type-IV units simultaneously. In contrast, the minimum loss reduction of 87.26% was observed by jointly allocating one unit of the aforementioned three DG types. Full article

A fundamental step to foster a sustainable future is enhancing students’ awareness of responsible food consumption. The present research study assessed students’ awareness of food waste (FW) issues, attitudes towards school catering and lunch management, and the reasons for plate waste (PW) in Rezekne city schools, Latvia. A survey was conducted in April 2024 involving 944 students in grades 2 to 7 across four selected schools (S1, S2, S3, and S4), provided with state and municipality-funded free lunches. Statistical analysis methods (Mean ± SD, Kruskal–Wallis H test, Mann–Whitney U post hoc test, and Spearman’s correlation analysis) were used to analyze the results. The findings revealed limited awareness and knowledge of students about FW issues, and generally indifferent attitude towards FW and school meals. In addition, significant dissatisfaction with the sensory qualities of meals was observed, yet sensory satisfaction did not correlate with FW levels, pointing to broader issues within the catering model. The restrictive pre-served portion system was found ineffective in reducing FW and fostering responsible consumption. A sustainable catering model should empower students to independently choose the type and quantity of food, combining their abilities and motivation with practical actions. These findings provide a basis for strategies aimed at reducing FW and promoting responsible and sustainable food consumption in Latvian schools. Full article

Background/Objectives: Test efficacy of the social emotional learning (SEL)-based Mighty Girls program, a program culturally tailored for English-speaking Hispanic/Latino girls in seventh grade comprised of classroom sessions and a virtual reality computer game. We hypothesized that the curriculum would decrease risky sexual behaviors in a program that can be used as part of a comprehensive sex education curriculum or as a stand-alone program. Methods: A randomized group trial was conducted in which 22 low-income, predominately Hispanic schools within the Miami-Dade County Public School System were randomly assigned to intervention (consented n = 335) and control (consented n = 217) conditions. All study activities occurred after school. Primary outcome measures were resistance self-efficacy, acceptance of dating violence, sexual intentions, and sexual behavior. Assessments occurred at baseline, immediately post-intervention, 3-, 12-, and 24-months post-intervention. Changes in outcomes from baseline to 24 months were modeled using multi-level models to account for nesting of students within schools with full information maximum likelihood to account for missing data and baseline school attendance and enrollment in free and reduced lunch as covariates. Analyses are also controlled for multiple testing. Results: The program had a significant effect on reducing acceptance of dating violence at 24 months post-intervention (estimate = −0.083, p ≤ 0.05), but no effect on resistance self-efficacy, sexual intentions, or sexual behavior (p ≥ 0.58). Conclusion: Study findings demonstrate that a social emotional learning (SEL) curriculum can impact sexual behaviors such as susceptibility to dating violence. Low baseline levels for sexual intentions and behaviors as well as a high baseline of efficacy may have impacted findings for the other outcomes. Full article

This study analyzed the statement “diversification is a free lunch”. We empirically showed that diversification is only a free lunch under uncertainty or ignorance, confirming Warren Buffett’s “diversification is protection against ignorance”. Using historical returns of the S&P500 constituents illustrated that diversification not only decreased the risk but also the returns if the expected returns could be estimated. The findings of this study highlight that diversification reduces risk but that the risk reduction is not for free. Full article

The No Free Lunch Theorem tells us that no algorithm can beat other algorithms on all types of problems. The algorithm selection structure is proposed to select the most suitable algorithm from a set of algorithms for an unknown optimization problem. This paper introduces an innovative algorithm selection approach called the CNN-HT, which is a two-stage algorithm selection framework. In the first stage, a Convolutional Neural Network (CNN) is employed to classify problems. In the second stage, the Hypothesis Testing (HT) technique is used to suggest the best-performing algorithm based on the statistical analysis of the performance metric of algorithms that address various problem categories. The two-stage approach can adapt to different algorithm combinations without the need to retrain the entire model, and modifications can be made in the second stage only, which is an improvement of one-stage approaches. To provide a more general structure for the classification model, we adopt Exploratory Landscape Analysis (ELA) features of the problem as input and utilize feature selection techniques to reduce the redundant ones. In problem classification, the average accuracy of classifying problems using CNN is 96%, which demonstrates the advantages of CNN compared to Random Forest and Support Vector Machines. After feature selection, the accuracy increases to 98.8%, further improving the classification performance while reducing the computational cost. This demonstrates the effectiveness of the first stage of the CNN-HT method, which provides a basis for algorithm selection. In the experiments, CNN-HT shows the advantages of the second stage algorithm as well as good performance with better average rankings in different algorithm combinations compared to the individual algorithms and another algorithm combination approach. Full article

Dietary recommendations to reduce the consumption of free sugars often group 100% fruit juice with other sugar-containing beverages. The objective of this study was to determine the effect of consuming 100% orange juice compared to an orange drink on next-meal food intake (FI), glycemic response, average appetite, emotions, and sensory characteristics in normal-weight adults. Thirty-six normal-weight adults (age: 26.8 ± 0.9 years) consumed, in random order and at least 5 days apart, three 240 mL test beverages as follows: (a) 100% orange juice, (b) orange drink, or (c) water. Subjective sweetness and pleasantness were determined immediately after test beverage consumption. Glycemic response, average appetite, and subjective emotions were measured every 15 min for 60 min. Food intake was determined at a pizza lunch 60 min later. Rest-of-day glycemic response and energy intake (EI) were determined using a continuous glucose monitor and food record, respectively. Lunch FI (p = 0.054) and total EI (p = 0.01) were both lower after 100% orange juice compared with the orange drink. Caloric compensation was 84% after 100% orange juice and −25% after the orange drink (p = 0.047). Average appetite was not significantly different between the test beverages (p > 0.05). Blood glucose iAUC adjusted for available carbohydrate was lower after 100% orange juice compared with the orange drink (p < 0.001). Rest-of-day blood glucose concentrations were lower after 100% orange juice compared with the orange drink (p = 0.03) and water control (p < 0.001). In conclusion, consumption of 100% orange juice as a preload resulted in higher caloric compensation, lower total daily EI, and lower blood glucose concentrations compared to the orange drink. Full article

This correlational study associated data on children enrolled in individualized educational plans in their K-12 schools (IEP) and an algorithm-calculated score of neurotoxins at contaminated sites located in each school district. The study also mapped and projected the correlations using Geographical Information System (GIS) technology. These data were populated in ArcMap 10.5 (a GIS software) for generating maps and data to conduct geospatial analysis. A total of 1 Superfund site and 39 CERCLA sites were identified as contaminated sites for this analysis. The majority of contaminants were heavy metals such as lead, arsenic, mercury, and cadmium. The mean toxic score of all contaminated sites combined was 13.4 (SD 14.4). Correlational analysis between the IEP numbers from each school district and toxic scores from the contaminated school district sites exhibited a positive relationship (F = 23.7, p < 0.0001). Correlations were also seen among higher toxics scores, IEP numbers, and children under the age of 10 (p < 0.00052) as well as higher proportions of black students in areas with high toxics scores (p = 0.0032). Black students were also far more likely to be enrolled in an IEP (p < 0.0001). Household income and poverty percentage in contaminated areas were also correlated (p = 0.0002). Individuals without college degrees were overrepresented in high toxic score school districts (p < 0.0001). The important low socio-economic status indicator of free and reduced lunch programs also correlated with increasing toxic scores (p = 0.0012) and IEP numbers (p = 0.0416). This study emphasizes the need to account for multiple exposures to wholistically appreciate environmental factors contributing to negative health outcomes. Full article

Previously, it has been indicated that oat polar lipids included in a liquid meal may have the potential to beneficially modulate various cardiometabolic variables. The purpose of this study was to evaluate the effects of oat polar lipids in a solid food matrix on acute and second meal glucose tolerance, blood lipids, and concentrations of gut-derived hormones. The oat polar lipids were consumed at breakfast and effects on the biomarkers were investigated in the postprandial period and following a standardized lunch. Twenty young, healthy subjects consumed in total four different breakfast meals in a crossover study design. The breakfasts consisted of 1. White wheat bread (WWB) with an added 7.5 g of oat polar lipids (PLL); 2. WWB with an added 15 g of oat polar lipids (PLH); 3. WWB with and added 16.6 g of rapeseed oil (RSO) as a representative of commonly consumed oils; and 4. WWB consumed alone, included as a reference. All products with added lipids contained equivalent amounts of fat (16.6 g) and available carbohydrates (50 g). Rapeseed oil was added to the oat polar lipid meals to equal 16.6 g of total fat. The standardized lunch was composed of WWB and meatballs and was served 3.5 h after the breakfast. Test variables (blood glucose, serum insulin, triglyceride (TG), free fatty acids (FFA), ghrelin, GLP-1, PYY, and GIP) were measured at fasting and repeatedly during the 5.5 h after ingestion of the breakfast. After breakfast, PLH substantially lowered postprandial glucose and insulin responses (iAUC 0–120 min) compared with RSO and WWB (p < 0.05). Furthermore, a reduced glycaemic response to lunch (210–330 min) was observed following the PLH breakfast compared to all of the other breakfasts served (p < 0.05). Oat polar lipids (PLH) significantly reduced TG and ghrelin and increased circulating gut hormones GLP-1 and PYY compared to RSO (p < 0.05). The results show that exchanging part of the dietary lipids with oat polar lipids has the potential to improve postprandial blood glucose regulation and gut hormones and thus may have a preventive effect against type 2 diabetes. Full article

We examined if areas around schools with more students of lower socioeconomic status (SES) have more total food/beverage advertisements and/or more advertisements with poorer nutritional content as compared to areas around schools with fewer students with lower SES. All outdoor food/beverage advertisements within a half-mile radius of 47 middle and high schools in the United States were objectively documented in 2012 and coded for nutritional content. The total number of advertisements and the macronutrient and micronutrient contents (total calories, fat (g), protein (g), carbohydrate (g), sugar (g), and sodium (mg)) of food and beverage items depicted in the advertisements were calculated. In total, 9132 unique advertisements were recorded, with 3153 ads displaying food and beverages that could be coded for nutrient content. Schools located in areas of lower SES (≥60% students receiving free/reduced-price lunch) had significantly more advertisements displaying food and beverages that could be coded for nutrient content (z = 2.01, p = 0.04), as well as advertisements that contained more sodium (z = 2.20, p = 0.03), as compared to schools located in areas of higher SES. There were no differences in calorie, fat, protein, carbohydrate, or sugar content. Policies to reduce the prevalence of outdoor food and beverage advertising are warranted. Full article

Background: Accurate assessment of self-reported appetite under free-living conditions is warranted to conduct large-scale intervention studies measuring appetite at a feasible cost. However, the performance of visual analogue scales (VASs) for this purpose has not been widely examined. Method: This randomized crossover trial was conducted to evaluate VASs in free-living vs. clinic-based settings and to assess appetite response following hypocaloric whole-grain rye and refined wheat diets. Twenty-nine healthy adults with overweight or obesity continuously answered VAS questions about their perceived appetite from morning to evening. Results: No differences in whole-day VAS scores (primary outcome) between clinic-based and free-living settings were observed, whereas measures of total area under the curve (tAUC) showed increased fullness in clinic-based interventions of 7% (p < 0.008) for whole-day responses and 13% (p < 0.03) following a snack. Appetite responses for a whole day did not differ between diets whereas rye-based dinners induced 12% (p < 0.016) higher fullness and reduced hunger by 17% (p < 0.02) irrespective of setting. A reduction in hunger of 15% (p < 0.05) was also observed following rye-based vs. wheat-based lunches. Conclusion: The results suggest that the VAS is valid for evaluation of appetite responses between diets under free-living conditions. No difference in self-reported appetite over the whole day was found after whole-grain rye vs. refined wheat-based diets, but there were some suggested differences at certain postprandial periods, in individuals with overweight or obesity. Full article

Little published research explores the perceptions of school nutrition professionals and youth regarding existing school nutrition marketing materials. A two-phased approach was taken to address this gap. In Phase 1, a national convenience sample of US school nutrition professionals (n = 1546; 89% female; 83.3% white; mean age 50 ± 10.2 years) evaluated a sample of marketing materials via a web-based survey. Phase 2 involved a sample of youth (n = 61; 51% female, 52.5% Hispanic; 98% participation in free/reduced price lunch) living in the Phoenix, Arizona metro area who completed interviews on the top-rated materials from the school nutrition professionals (Phase 1). Main outcome measures included perceived attractiveness/appeal, comprehension, relevance, motivation/persuasion, and uniqueness of marketing materials. In Phase 1, means/standard deviations of school nutrition professionals’ perceptions across materials are provided. For Phase 2, a thematic/subtheme analysis of the youth interviews is provided. School nutrition professionals found the materials easy to understand (82%); however, they rated the materials low in motivational appeal (48%) and low in their ability to influence the selection or consumption of fruits/vegetables (95%). Youth participants discussed their likes, dislikes, comprehension, social aspects, and health aspects of the materials. Results indicate that existing marketing materials were not highly rated by professionals or youth. Greater investment and research are needed to test and develop nutrition marketing materials for schools, with a focus on enhancing their appeal and impact on fruit/vegetable consumption. Full article