The State of the Summer: a Review of Child Summer Weight Gain and Efforts to Prevent It

Seasonal variability in body mass index, waist circumference, and skinfolds in Norwegian children

OBJECTIVES

Studies have shown that children develop a higher body weight during summer months. This has been demonstrated repeatedly using the body mass index (BMI), but the effect of season on other weight-related anthropometric measurements is still unclear.

METHODS

Measurements of height, weight, waist circumference (WC), triceps, and subscapular skinfolds (TSF and SSF), collected from September till May in a cross-sectional sample of 4-16-year-old children and adolescents (n = 4525) from the Bergen Growth Study 1 (BGS1). Differences in z-score by season were tested with linear models adjusted for age group and separately for sex. Overall differences were tested with a one-way between-group analysis of variance.

RESULTS

The girls had higher BMIz (+0.12, p = .03) and WCz (+0.18, p = .002) in fall compared with spring. TSFz (-0.19, p < .001) and SSFz (-0.18, p < .001) were lower in winter in girls, and in boys both in fall (TSFz -0.10, p = .046; SSFz - 0.16, p < .001), and winter (TSFz -0.15, p = .004; SSFz -0.14, p = .003), when compared with spring.

CONCLUSIONS

Seasonal variation was detected for all anthropometric measures, but differences in the direction of the effect between measures of global (BMI), central (WC) or subcutaneous (SF) adiposity suggest a more complex mechanism that needs further exploration.

The Effects of COVID-19 Virtual Learning on Body Fat and Insulin Resistance in Adolescents with Overweight or Obesity

(1) Background: COVID-19 virtual learning reduced structural supports for adolescent physical activity and diet, threatening metabolic health, especially in teens with overweight or obesity (OWOB). (2) Methods: Adolescents (N = 14) with OWOB completed fasting blood draws (measuring insulin resistance, IR) and Dual Energy X-Ray Absorptiometry (DXA, measuring total body fat percent, TBF%) pre-COVID-19 and during COVID-19. Changes in TBF% and IR were calculated (1) pre-COVID-19 and (2) from pre-COVID-19 to during COVID-19. Age and body mass index (BMI) percentile-matched data assessed normative changes across similar, non-COVID-19 time periods. Paired t-tests compared TBF% change pre- to during COVID-19 with (1) TBF% change pre-COVID19 and (2) TBF% normative change. Two ANCOVAs compared IR change pre- to during COVID-19 with (1) IR change pre-COVID-19 controlling for BMI z-score and difference in time between assessments and (2) normative change in IR controlling for sex/race. (3) Results: The TBF% change pre-COVID-19 and the normative change were similar. The TBF% increased more (~six percentage points) during COVID-19 compared to normative change (p < 0.01). During COVID-19, IR increased more (~2.5 units) than change pre-COVID-19 (p = 0.03) and increased more (~3.5 units) than normative change (p = 0.01). (4) Conclusions: TBF% and IR increased exponentially during COVID-19 in teens with OWOB compared to pre-COVID-19 and normative changes.

Effects of a Summer Physical Activity Program on Fitness and Cognitive Function among Children from Low Socioeconomic Households

During the summer months, school aged children experience a loss in academic gains made over the course of the school year, as well as engage in poorer health behaviors such as decreased physical activity and poor diet that can lead to excess weight gain. This study aimed to assess changes in body composition, fitness, and cognitive abilities in children from low-income households after a summer physical activity program and explored whether time spent in moderate to vigorous physical activity (MVPA) was related to these changes. Participant's (N = 77) body composition, aerobic fitness (i.e., PACER), and cognitive function (i.e., modified flanker task) were measured during week 1 and week 3. MVPA was collected via hip accelerometer worn during program hours. Paired t-tests and regression analyses were conducted to determine changes between week 1 and 3, whether participation was related to changes in fitness, adiposity, and cognitive function. T-tests revealed significant changes in PACER score (10.71 ± 7.72 to 13.301 ± 10.68; p < 0.001) and incongruent accuracy on the flanker task (65.94% ± 23.83 to 69.00% ± 21.89; p < 0.006), however no significant change in BMI-for-age percentile or body fat percentage was detected. Additionally, regression analyses revealed no significant relationship between change in MVPA or attendance, and changes in PACER, flanker task performance, BMI, or body fat percentage. Children that participated in a summer physical activity program targeted toward children affected by poverty exhibited significant improvements in cardiorespiratory fitness and cognitive abilities, and no changes in body composition.

Association between Types of Screen Time and Weight Status during the COVID-19 Pandemic: A Longitudinal Study in Children and Adolescents

BACKGROUND

This study aimed to investigate the changes in distinct types of screen time and explore their longitudinal association with children and adolescents' weight status.

METHODS

A two-wave longitudinal study was conducted among 2228 children and adolescents (6-19 years) in Shanghai, China, before and during the pandemic. Recreational screen time (watching TV/videos, online gaming, using social media, and browsing webpages), educational screen time (online homework and online class), and BMI were measured using a self-reported questionnaire. Mixed-effects models were constructed to assess the associations between screen time and weight status.

RESULTS

The prevalence of overweight and obesity was 20.5% and 10.2% at baseline, respectively. Both recreational and educational screen time increased significantly over two months. While recreational screen time was found to be a risk factor for obesity, it was not the case for educational screen use. Specifically, adolescents who spent more time watching TV/videos had a higher obesity risk (OR = 1.576). No significant associations were found in children.

CONCLUSIONS

Overweight and obesity were prevalent among children and adolescents in China. Reducing screen-based activities is a promising strategy to prevent unhealthy weight gain in Chinese children and adolescents, while it is necessary to consider the content and distinguish between educational and recreational screen use.

Longitudinal changes in juvenile and adolescent body mass indices before, during, and after the COVID-19 lockdown in New Zealand

OBJECTIVE

This study uses longitudinal data from school children in Dunedin, New Zealand, to evaluate impacts of COVID-19 lockdown measures on changes in body mass (BMI, kg/m² ). Impacts are assessed using two non-mutually exclusive hypotheses. The "structured days" hypothesis holds that children tend to alter sleep patterns, reduce activity and increase snacking when not in structured environments. The bidirectional hypothesis proposes that over-weight or obese children are predisposed to further gains in unstructured settings.

METHODS

Juveniles and adolescents (n = 95, 60% female) were recruited from Dunedin schools. Repeated measures analyses assessed variation in intra-individual change in BMI during four periods: P1 (before summer break), P2 (during summer break), P3 (during the COVID-19 lockdown), and P4 (after the lockdown ended). The model also examined if these changes were influenced by participants' sex or body size early in the first period assessed using log-transformed BMI, log-transformed weight, height, or lower leg length.

RESULTS

Repeated measures analyses of per month gains in BMI (kg/m² ) during the four periods revealed consistent period (p ≤ .001), period by sex (p ≤ .010), and period by body size (p ≤ .001) interactions across all four body size proxies. Both sexes experienced the greatest gains during the lockdown (P3), but differed in response to their summer break (P2).

CONCLUSION

Results are mostly consistent with the "structured days" hypothesis, but challenge the bidirectional hypothesis as defined. Further research better characterizing risks of gains in adiposity are needed.

Integration of Time-Based Recommendations with Current Pediatric Health Behavior Guidelines: Implications for Obesity Prevention and Treatment in Youth

PURPOSE OF REVIEW

Youth-onset obesity is associated with negative health outcomes across the lifespan including cardiovascular diseases, type 2 diabetes, obstructive sleep apnea, dyslipidemias, asthma, and several cancers. Pediatric health guidelines have traditionally focused on the quality and quantity of dietary intake, physical activity, and sleep.

RECENT FINDINGS

Emerging evidence suggests that the timing (time of day when behavior occurs) and composition (proportion of time spent allocated to behavior) of food intake, movement (i.e., physical activity, sedentary time), and sleep may independently predict health trajectories and disease risks. Several theoretically driven interventions and conceptual frameworks feature behavior timing and composition (e.g., 24 h movement continuum, circadian science and chronobiology, intermittent fasting regimens, structured day hypothesis). These literatures are, however, disparate, with little crosstalk across disciplines. In this review, we examine dietary, sleep, and movement guidelines and recommendations for youths ages 0-18 in the context of theoretical models and empirical findings in support of time-based approaches. The review aims to inform a unifying framework of health behaviors and guide future research on the integration of time-based recommendations into current quantity and quality-based health guidelines for children and adolescents.

Changes in BMI During the COVID-19 Pandemic

BACKGROUND AND OBJECTIVES

Experts hypothesized increased weight gain in children associated with the coronavirus disease 2019 (COVID-19) pandemic. Our objective was to evaluate whether the rate of change of child body mass index (BMI) increased during the COVID-19 pandemic compared with prepandemic years.

METHODS

The study population of 1996 children ages 2 to 19 years with at least 1 BMI measure before and during the COVID-19 pandemic was drawn from 38 pediatric cohorts across the United States participating in the Environmental Influences on Child Health Outcomes-wide cohort study. We modeled change in BMI using linear mixed models, adjusting for age, sex, race, ethnicity, maternal education, income, baseline BMI category, and type of BMI measure. Data collection and analysis were approved by the local institutional review board of each institution or by the central Environmental Influences on Child Health Outcomes institutional review board.

RESULTS

BMI increased during the COVID-19 pandemic compared with previous years (0.24 higher annual gain in BMI during the pandemic compared with previous years, 95% confidence interval 0.02 to 0.45). Children with BMI in the obese range compared with the healthy weight range were at higher risk for excess BMI gain during the pandemic, whereas children in higher-income households were at decreased risk of BMI gain.

CONCLUSIONS

One effect of the COVID-19 pandemic is an increase in annual BMI gain during the COVID-19 pandemic compared with the 3 previous years among children in our national cohort. This increased risk among US children may worsen a critical threat to public health and health equity.

Seasonality of Children’s Height and Weight and Their Contribution to Accelerated Summer Weight Gain

Background: While children have been shown to have increased BMI during the summer compared to the school year, it is not known if this may be due to seasonal variations in height or weight separately.

Methods: Trained nurses measured heights (cm) and weights (kg) in a cohort of Kindergarteners (n = 7648) twice per year from the beginning of kindergarten through 5th grade. Variation in height and weight by season (school year vs. summer) was examined using separate mixed-effects models. Season, sex, and BMI trajectory group were tested as fixed effects. Random effects included repeated measurements of time, students nested within a school, intercept, and slope for growth over time. Similar models using BMIz as the outcome examined the interaction of height or weight with season.

Results: The rate of height gain was greater during the school year (∼Sept to April) compared to summer (∼April to Sept) (β = -0.05, SE = 0.013, p < 0.0001). The rate of weight gain did not differ seasonally. Height gain was more strongly associated with increased BMIz during summer compared to the school year (β =.02, SE = 0.005, p <0 .0001), mainly among children who remained healthy weight throughout elementary school (β = 0.014, SE = 0.003, p < 0.0001) and those who transitioned to a healthier weight status (β = 0.026, SE = 0.008, p = 0.004). We found a similar seasonal effect for the association between weight with BMIz among children who maintained a healthy weight status (β = 0.014, SE = 0.014, p < 0.0001).

Conclusion: This study indicates seasonality in children’s height gain, gaining height at a faster rate during the school year compared to the summer, while weight gain remained relatively more consistent throughout the year. Seasonality in height and weight gain had the greatest impact on BMIz among children with a healthy weight status. Future research with more frequent measurements is needed to better understand the seasonal regulation of children’s growth and weight gain.

A Socioecological Perspective of How Physical Activity and Sedentary Behaviour at Home Changed during the First Lockdown of COVID-19 Restrictions: The HomeSPACE Project

The COVID-19 pandemic forced school closures, resulting in home schooling, more time spent at home and fewer opportunities for physical activity (PA). This study explored factors influencing PA and sedentary behaviours (SB) within the home environment during the first lockdown, starting in March 2020. Twenty semi-structured interviews (20 parents and 23 children, 12 years ± 1.25) were conducted. Data were coded using thematic analysis on NVivo© and concepts from McLeroy’s socioecological model for health promotion were used to analyse the data. Findings indicate that children’s PA and SB at home were influenced by: (i) individual-level factors (e.g., gender, competence, attitudes and motivation); (ii) interpersonal-level factors (e.g., siblings, parents, pets, friends and coaches); (iii) organisation-level factors (e.g., school, clubs and societies), (iv) community-level factors (e.g., home and local environment, access to facilities, social norms, time constraints and home equipment), and (v) policy-level factors (e.g., lockdown restrictions). Stay-at-home mandates resulted in perceived reductions in PA and increases in SB within the home; however, this provided alternative positive opportunities for families, including more time to spend together and exploring green and blue spaces in the local area.

Impacts of the COVID-19 Pandemic on Children's Sugary Drink Consumption: A Qualitative Study

The coronavirus (COVID-19) pandemic has caused striking alterations to daily life, with important impacts on children's health. Spending more time at home and out of school due to COVID-19 related closures may exacerbate obesogenic behaviors among children, including consumption of sugary drinks (SDs). This qualitative study aimed to investigate effects of the pandemic on children's SD consumption and related dietary behaviors. Children 8–14 years old and their parent (n = 19 dyads) participated in an in-depth qualitative interview. Interviews were recorded, transcribed verbatim, and independently coded by two coders, after which, emergent themes and subthemes were identified and representative quotations selected. Although increases in children's SD and snack intake were almost unanimously reported by both children and their parents, increased frequency of cooking at home and preparation of healthier meals were also described. Key reasons for children's higher SD and snack intake were having unlimited access to SDs and snacks and experiencing boredom while at home. Parents also explained that the pandemic impacted their oversight of the child's SD intake, as many parents described loosening prior restrictions on their child's SD intake and/or allowing their child more autonomy to make their own dietary choices during the pandemic. These results call attention to concerning increases in children's SD and snack intake during the COVID-19 pandemic. Intervention strategies to improve the home food environment, including reducing the availability of SDs and energy-dense snacks and providing education on non-food related coping strategies are needed.

The Impact of Waivers on Summer Meal Participation in Maryland

BACKGROUND

The Summer Food Service Program (SFSP) is a federally funded program that serves free, nutritious meals during the summer months. In 2019, 6 federal waivers that previously helped sponsors serve meals were rescinded. The purpose of this mixed methods study was to assess the impact of the waiver rescission on the experiences of SFSP sponsors in Maryland.

METHODS

This study analyzed responses from Maryland SFSP sponsors in a quantitative online survey and linked meal participation data for 2018 and 2019 (n = 29) and in-depth interviews (n = 11) about their experiences serving summer meals.

RESULTS

Most respondents reported that the waiver rescission significantly impacted their experience serving meals, including increases in workload, spending and staffing; reductions in meal types (eg, breakfast); fewer meals served; and changing closed sites to open. Sponsors expressed desire for the state to apply for waivers on behalf of all SFSP sponsors in future years.

CONCLUSION

The federal rescission of USDA summer meals waivers created substantial barriers for sponsors. To address the issues created by policy decisions, school food authorities and other SFSP should continue to work with researchers and antihunger advocates to share their experiences in order to shape state programs and policies.

Later sleep timing predicts accelerated summer weight gain among elementary school children: a prospective observational study

OBJECTIVES AND BACKGROUND

Social demands of the school-year and summer environment may affect children's sleep patterns and circadian rhythms during these periods. The current study examined differences in children's sleep and circadian-related behaviors during the school-year and summer and explored the association between sleep and circadian parameters and change in body mass index (BMI) during these time periods.

METHODS

This was a prospective observational study with 119 children ages 5 to 8 years with three sequential BMI assessments: early school-year (fall), late school-year (spring), and beginning of the following school-year in Houston, Texas, USA. Sleep midpoint, sleep duration, variability of sleep midpoint, physical activity, and light exposure were estimated using wrist-worn accelerometry during the school-year (fall) and summer. To examine the effect of sleep parameters, physical activity level, and light exposure on change in BMI, growth curve modeling was conducted controlling for age, race, sex, and chronotype.

RESULTS

Children's sleep midpoint shifted later by an average of 1.5 h during summer compared to the school-year. After controlling for covariates, later sleep midpoints predicted larger increases in BMI during summer, (γ = .0004, p = .03), but not during the school-year. Sleep duration, sleep midpoint variability, physical activity levels, and sedentary behavior were not associated with change in BMI during the school-year or summer. Females tended to increase their BMI at a faster rate during summer compared to males, γ = .06, p = .049. Greater amounts of outdoor light exposure (γ = -.01, p = .02) predicted smaller increases in school-year BMI.

CONCLUSIONS

Obesity prevention interventions may need to target different behaviors depending on whether children are in or out of school. Promotion of outdoor time during the school-year and earlier sleep times during the summer may be effective obesity prevention strategies during these respective times.

Preliminary Evidence of Children’s Weight Gain From 5 Months of Home Quarantine During the COVID-19 Pandemic

Purpose. Preventive measures to curtail the spread of the Coronavirus Disease 2019 (COVID-19)—such as home quarantine, closure of schools/programs—are necessary, yet the impact of these restrictions on children’s weight status is unknown. The purpose of this case report was to investigate changes in children’s body mass index (BMI) and zBMI during COVID-19 quarantine. Methods. Children had their heights and weights recorded early March 2020 (pre-COVID-19) and 5 months later (early August 2020). Paired sample t tests examined changes in BMI and zBMI from baseline to follow-up. Results. Twenty-nine children (62% female; mean age 9.3 years; 27.5% with overweight or obesity) provided height and weight data at both time points. There was a significant difference in pre-COVID-19 BMI (mean [M] = 20.1, standard deviation [SD] = 6.0) and follow-up BMI (M = 20.7, SD = 6.4); t(57) = −3.8, P < .001, and pre-COVID-19 zBMI (M = 0.8, SD = 0.9) and follow-up zBMI (M = 0.9, SD = 0.9); t(57) = -3.1, P = .003. Five of the 29 children moved from normal weight to overweight (n = 4) or obese (n = 1) during 5 months of quarantine. Conclusions. Preliminary evidence shows most children increased their BMI and zBMI values from pre-COVID-19 assessment to the follow-up assessment, 5 months later. These initial findings identify potential incidental negative health consequences of children as a result of COVID-19 preventative measures such as home quarantine.

Summer Weight Gain Among Preschool-Aged Children With Obesity: An Observational Study in Head Start

School-aged children gain weight most rapidly in summer, but few studies have investigated summer weight gain among preschool-aged children. We fit continuous linear spline mixed models to test for accelerated summer weight gain among 2,044 children attending 16 Boston-area Head Start programs between fall 2016 and spring 2019. Academic year and summer rates of change in modified body mass index z-score differed (P < .001), with accelerated summer weight gain most pronounced among children with obesity. As with school-aged children, increased focus on the summer is warranted for promoting healthy weight among children in Head Start.

COVID-19-Related Weight Gain in School-Aged Children

Collapse

Early effects of the COVID-19 pandemic on physical activity and sedentary behavior in children living in the U.S

Background

COVID-19 restrictions such as the closure of schools and parks, and the cancellation of youth sports and activity classes around the United States may prevent children from achieving recommended levels of physical activity (PA). This study examined the effects of the COVID-19 pandemic on PA and sedentary behavior (SB) in U.S. children.

Method

Parents and legal guardians of U.S. children (ages 5–13) were recruited through convenience sampling and completed an online survey between April 25–May 16, 2020. Measures included an assessment of their child’s previous day PA and SB by indicating time spent in 11 common types of PA and 12 common types of SB for children. Parents also reported perceived changes in levels of PA and SB between the pre-COVID-19 (February 2020) and early-COVID-19 (April–May 2020) periods. Additionally, parents reported locations (e.g., home/garage, parks/trails, gyms/fitness centers) where their children had performed PA and their children’s use of remote/streaming services for PA.

Results

From parent reports, children (N = 211) (53% female, 13% Hispanic, M_age = 8.73 [SD = 2.58] years) represented 35 states and the District of Columbia. The most common physical activities during the early-COVID-19 period were free play/unstructured activity (e.g., running around, tag) (90% of children) and going for a walk (55% of children). Children engaged in about 90 min of school-related sitting and over 8 h of leisure-related sitting a day. Parents of older children (ages 9–13) vs. younger children (ages 5–8) perceived greater decreases in PA and greater increases in SB from the pre- to early-COVID-19 periods. Children were more likely to perform PA at home indoors or on neighborhood streets during the early- vs. pre-COVID-19 periods. About a third of children used remote/streaming services for activity classes and lessons during the early-COVID-19 period.

Conclusion

Short-term changes in PA and SB in reaction to COVID-19 may become permanently entrenched, leading to increased risk of obesity, diabetes, and cardiovascular disease in children. Programmatic and policy strategies should be geared towards promoting PA and reducing SB over the next 12 months.

Effects of Four-Day School Weeks on Physical Education Exposure and Childhood Obesity

BACKGROUND

Use of 4-day school weeks (FDSWs) as a cost-saving strategy has increased substantially as many US school districts face funding declines. However, the impacts of FDSWs on physical activity exposure and related outcomes are unknown. This study examined physical education (PE) exposure and childhood obesity prevalence in 4- versus 5-day Oregon schools; the authors hypothesized lower PE exposure and higher obesity in FDSW schools, given reduced school environment exposure.

METHODS

The authors utilized existing data from Oregon to compare 4- versus 5-day models: t tests compared mean school-level factors (PE exposure, time in school, enrollment, and demographics) and complex samples weighted t tests compared mean child-level obesity data for a state representative sample of first to third graders (N = 4625).

RESULTS

Enrollment, time in school, and student-teacher ratio were significantly lower in FDSW schools. FDSW schools provided significantly more PE, both in minutes (120 vs 101 min/wk in 4- vs 5-d schools, P < .01) and relative to total time in school (6.9% vs 5.0%, P < .0001). Obesity prevalence did not differ significantly between school models.

CONCLUSION

Greater PE exposure in FDSW schools was observed, and it remains unknown whether differences in PE exposure contributed to obesity prevalence in this sample of students. Efforts to better understand how FDSWs impact physical activity, obesity risk, and related factors are needed.

The Diet Quality of a Sample of Predominantly Racial Minority Children From Low-Income Households Is Lower During the Summer vs School Year: Results From the Project Summer Weight and Environmental Assessment Trial Substudy

BACKGROUND

Little is known about the diet quality of racial minority children during the summertime when school is out of session and there is risk of accelerated weight gain. Project Summer Weight and Environmental Assessment Trial was an observational, prospective study exploring child weight status and health trends during the summer.

OBJECTIVE

The objective of this substudy of Project Summer Weight and Environmental Assessment Trial was to examine the diet quality of elementary-aged racial minority children during the summertime vs school year.

DESIGN

This observational, prospective substudy was conducted from June to September 2017.

PARTICIPANTS/SETTING

Students in prekindergarten through fifth grade were recruited from 2 schools located in low-income urban neighborhoods of Columbus, OH, with a predominantly Black population. Sixty-two children (39 families) enrolled.

MAIN OUTCOME MEASURES

Twenty-four-hour dietary recalls (2 weekdays, 1 weekend day) were collected at 3 time points: (1) beginning of summer (T0); (2) midsummer (T1); and (3) beginning of subsequent school year (T2). Healthy Eating Index (HEI)-2015 total and component scores were calculated to assess diet quality. Daily calories (kilocalories) and servings of types of foods within food groups were also assessed.

STATISTICAL ANALYSES

Repeated measures analysis of variance and Tukey's post hoc analyses were performed.

RESULTS

Retention was 76% (n = 47). Mean age was 7.0 ± 0.3 years, 79% (n = 37) were African American, and 58% of participants (n = 26) reported annual household incomes ≤$20,000. HEI-2015 total score was significantly lower during the summertime vs school year (P = .02). HEI-2015 component score for whole fruits (P = .04) was also lower in the summer vs school year, along with total vegetables (P < .001), greens and beans (P < .001) specifically, and legumes (P < .001). The HEI-2015 component score for added sugars (P = .04) was significantly lower in the summer vs the school year as well, indicating a higher intake of added sugars during the summer. On the other hand, whole grains were higher during the summer vs school year (P < .01), specifically snack chips (P = .03) and popcorn (P < .01). Total daily calories did not differ between the summertime vs school year.

CONCLUSIONS

In a small sample of predominantly racial minority school-aged children from low-income households, child diet quality is better during the school year vs summer. Future research is needed to determine if and to what extent summer vs school year diet quality may be associated with differences in weight status.

The Academic, Behavioral, and Health Influence of Summer Child Nutrition Programs: A Narrative Review and Proposed Research and Policy Agenda

Since 1975, the US Department of Agriculture has sponsored the Summer Food Service Program as a nationwide strategy for providing nutritious meals to children and youth (aged 18 years or younger) in low-income communities during the summer months. Many programs are sponsored by community organizations as well as school districts that may offer the program through the Summer Food Service Program or a seamless waiver, allowing them to extend school meals programs into the summer. These summer nutrition programs are designed to decrease food insecurity and improve health outcomes among at-risk populations. However, the characteristics of these programs, including the types of participants reached, and the programs' influence on outcomes such as academics, behavior, and physical and mental health, have not been summarized. The aims of this narrative review are to present existing knowledge about the characteristics of summer nutrition programs and their influence on students, to identify knowledge gaps, and to identify future research needs. An extensive search identified eight peer-reviewed articles and 10 reports, briefs, or other documents reporting research on the Summer Food Service Program. A variety of additional literature was reviewed to provide relevant information about summer nutrition programs. The review revealed a dearth of research regarding current Summer Food Service Program implementation. Summer nutrition programs alleviated food insecurity among at-risk populations; however, little research was found about the influence of summer programs on students' dietary intake or weight outcomes. More rigorous and mixed-methods studies examining the characteristics and influence of summer nutrition programs are needed.