Skip to main content

Evaluating the impacts of school garden-based programmes on diet and nutrition-related knowledge, attitudes and practices among the school children: a systematic review

Abstract

Background

Previous evidence suggests that school garden-based programmes (SGBP) may be a promising yet cost-effective intervention to improve children’s knowledge, attitudes and practices (KAP) on healthy eating. This review aimed to summarise and evaluate the evidence available on the impacts of SGBP in addressing diet and nutrition-related KAP among school-aged children.

Methods

Five databases including PubMed, Embase, Cochrane, Web of Science and Scopus were searched until February 2021. Randomised, non-randomised controlled and pre-post intervention studies investigating the impacts of SGBP on at least one of the outcomes of interest including diet and nutrition-related knowledge, attitudes towards fruits and vegetables (F&V), food diversity and dietary practice among school-aged children were included. Study selection and data extraction were performed by one reviewer and checked for accuracy by the other two reviewers in accordance with PRISMA guideline. Quality appraisal for studies included was assessed using American Dietetic Association Quality Criteria Checklist.

Results

A total of 10,836 records were identified, and 35 studies that met the inclusion and exclusion criteria were included. This includes 25,726 students from 341 schools and 8 nurseries from 12 countries. Intervention duration ranged from 6 weeks to 4 years with 18 studies involving a varied degree of parental participation. SGBP, which majorly includes school gardening activities, cooking lessons and nutrition education, demonstrated beneficial effects on children’s nutritional knowledge, their attitudes and acceptability towards fruits and vegetables and children’s dietary practices including the actual F&V consumption and dietary diversity. However, the impacts of SGBP on such outcomes were highly influenced by various social and environmental factors including the activities/components and duration of the intervention, parental involvement, sample size, and the age of children when interventions were first introduced.

Conclusion

These findings suggest that SGBP may be effective in promoting children’s nutritional knowledge, attitudes and acceptability towards vegetables, however, the impacts may vary by the type, the extent, and the length of the programmes, and other factors such as parent involvement. Future SGBP is suggested to implement using a combined multidisciplinary approach targeting the children, parents, and community to effectively promote healthy eating among the children and prevent childhood obesity.

Peer Review reports

Introduction

Childhood malnutrition in all forms is affecting every country in the world [1]. In the past four decades, a tenfold increase was reported in the number of obese children and adolescents aged 5 to 19 worldwide, from 11 million in 1975 to 124 million in 2016 with an addition of 213 million being classified as overweight [2]. Concerningly, childhood malnutrition is likely to persist into adulthood, which can perpetuate an ill-health cycle, increasing the health risk in their later life [3]. Suboptimal diets with poor dietary behaviour are one of the major contributing factors for both the obesity and nutritional or micronutrient deficiencies. A healthy diet, according to the World Cancer Research Fund [4] and WHO [5], is characterised by the consumption of abundant whole grains, legumes, fruits, vegetables, and nuts with a limited intake of salt, red and processed meat, sugar and fat-rich “fast food” and other processed food. Diet rich in fibre and fruits and vegetables (F&V) e.g., Mediterranean diet, has shown positive effects on tackling obesity [6,7,8,9,10]. Despite prominent benefits of F&V, current consumption level remains low in young people. A survey of ten European countries reported that only 23.5% of the studied children met the WHO requirement of no less than 400 g of F&V per day and more than half of the children do not consume fruits on a daily basis [11].

According to the PRECEED-PROCEED model, behavioural change occurs under the changes of its determinants [12]. In other words, having a deeper understanding of its underlying determinant is the first step in improving diet quality among children. Compelling evidence suggested that F&V consumption is driven by knowledge and awareness of, preference for and attitude towards such foods [13]. Food preferences and dietary habits are generally shaped at an early age, and they are more likely to persist into adulthood and affect our food choices in later life [14,15,16]. Therefore, there is a need to enhance nutritional knowledge and encourage early F&V exposure among the children, to promote their willingness to consume, acceptance and liking of F&V [17,18,19,20,21].

Recent evidence suggested that school garden-based programmes (SGBP) may be a promising yet cost-effective intervention to promote healthy eating habits and increase children’s F&V intake with a potential to reduce food neophobia, which is defined as the reluctance to consume novel foods [22]. School is regarded as a prime setting to shape children’s dietary behaviour whereby 20% of their daily dietary intake are obtained [23, 24]. SGBP, which enhance the circular learning environment by integrating a hands-on experimental approach, may strengthen the impact of nutrition education on children. The hands-on activities include direct gardening experiences and active involvement in designing, building, developing and maintaining the school garden with edible plants [21, 25]. Other activities may include bed preparation, seed planting, seedlings transplanting, plant growing and nurturing, and application of organic pest control [26, 27]. Growing own produces not only can increase school and/or home accessibility and availability of F&V, but also encourage children to appreciate and value garden produce [24, 25]. This may eventually increase children’s preferential selection, willingness to taste and potentially the intake of F&V. In addition to single-component SGBP interventions, multicomponent school garden-based interventions that integrate gardening with classroom curriculum, physical education, cooking session, food service, and/or with parental involvement displayed a more promising effect in promoting children’s F&V consumption and its determinants [23, 25, 28].

Despite greater potential evidence on SGBP effects towards improving knowledge, attitudes and practices (KAP) regarding diet and nutrition remain mixed. Therefore, this study aimed to systematically review the available evidence on the impacts of SGBP on diet and nutrition-related KAP among school-aged children, and to explore the key features of its effectiveness.

Methods

Search strategy

The search was conducted between 11th November 2020 to 6th February 2021. Five databases were used, including PubMed, Embase, Cochrane, Web of Science and Scopus for primary research articles published from year 2000. This timeframe was chosen with the aim of obtaining the most recent SGBP intervention studies. The following search terms were used: (1) school children as the targeted population: adolescent* OR boy? OR child* OR children OR girl? OR juvenil* OR kid? OR preschool* OR school* OR teen* OR youth* OR young OR “school children” OR student*; (2) school setting: school* OR nurser* OR kindergarten* OR kindergarden*; (3) garden-based interventions: garden* OR gardening OR plant* OR fruit* OR vegetable* OR “fruit vegetable*” OR “fruit growing” OR “vegetable growing” OR seed* OR tree* OR “organic agriculture” OR “organic farming” OR “organic food” OR farm; (4) outcome measures on diet and nutritional related KAP: (eating OR diet* OR food OR dietary OR nutrition OR nutritional OR fruit* OR vegetable*) AND (knowledge OR attitude OR practi?e* OR behavio?r* OR preference* OR habit* OR intake* OR consumption* OR healthy OR skill* OR pattern* OR diversity OR diverse OR perception*) OR “energy intake” OR “appetite” OR “portion size*” OR “food fussiness” OR “food neophobia”; (5) study design: “controlled trial*” OR “intervention” OR randomised OR randomized OR trial* OR “randomised controlled trial*” OR “randomized controlled trial*” OR follow-up stud* OR program evaluation*” OR “controlled before-after stud*”. Details of the search strategies used for each database are presented in the Supplementary Table 1.

Inclusion and exclusion criteria

Studies were included if they met the following inclusion and exclusion criteria.

Inclusion criteria

Population

School children and adolescents (boys and girls) aged 3–18 years old attending nursery, kindergarten, primary, secondary or high school education and special school. Children under the age of 3 and over the age of 18 would still be included as long as they were being classified as “students” or still attending nurseries, kindergarten or high schools.

Interventions

Studies that used school gardening, kitchen-gardening, garden curriculum or horticulture activities as primary interventions were included. Gardening activities included cultivating plants such as fruits, vegetables, shrubs, flowers and trees while gardening programmes included activities such as preparing the soil, sowing seeds, planting, weeding, watering and harvesting, hands-on learning with fruits and vegetables, education on food origins and systems, and the fresh produce’s production. Garden-related cooking and tasting activities were also included. Gardening programmes could be conducted within the school curriculum or conducted out of the lesson time such as during recess, lunchtime or after-school activities and school trips to community allotments.

Outcomes

Studies with a result for at least one outcome of interest were included, including examining food literacy such as diet and nutrition-related knowledge, attitudes, skills, preferences, behaviours and practices e.g., dietary diversity and F&V intake.

Study design

Randomised controlled trials in which individuals or clusters (classes or schools) were randomly assigned to trial arms, non-randomized controlled trials and pre-post intervention studies which examined the changes in the outcome measures at post-intervention and baseline were included. Only studies written in English were included. No restrictions were placed on the author, sample size, funding sources of study, duration of the intervention or the country where the intervention took place.

Exclusion criteria

Garden-based interventions that did not organise by the school such as community-based gardening programmes, community youth interventions, summer holiday extra-curricular activities or clubs were excluded. Study organised by the school but occurred at the community level such community gardens, however, were included as the participants were still being regarded as “students”. Interventions with only teaching gardening related knowledge without actual hand-on gardening component were excluded. Studies that did not regard school gardening as their primary intervention or did not specify the age of participants were also excluded. Studies that only focused on describing school-based gardening programme without addressing its effects on nutritional KAP were excluded. Editorials, commentaries, opinions, review articles and observational studies such as cross-sectional studies, prospective and retrospective cohort studies were not included as well as unpublished, grey literature and ongoing studies with only preliminary findings.

Study selection

Studies obtained from the search were uploaded to ENDNOTE (X7, Thomson Reuters). Screening and selection of studies for inclusion in this review were performed by a reviewer and the decisions were checked by the other reviewer. During the first round of screening, the title and abstract were checked for eligibility based on the inclusion and exclusion criteria. In the second round of screening, full-text articles were obtained and screened for eligibility using the same criteria. Disagreement between reviewers was resolved by discussion and by a third reviewer.

Data extraction

A standardized data extraction form was utilized to obtain the following information, where possible: author, year of publication, journal source, source of funding, study design, year of study, country or population, sample characteristics (e.g., gender, age, socioeconomic status etc.), sample size, intervention size, control size, intervention group description (activities included in the SGBP), control group description, duration of intervention, outcome measures (e.g., indicators related to KAP around diet and nutrition) and main findings. Any disagreements were resolved through discussion with the research team.

Strategy for data synthesis

A systematic review synthesising the qualitative evidence of school garden-based programmes was conducted. The findings on the impact of school garden-based programmes in affecting school children’s KAP around diet and nutrition were reported according to the components of the interventions via categorising them into school garden-based programmes with and without parental involvement. A meta-analysis on any of the quantitative data extracted was unable to be performed due to the heterogeneity and variation in the study design, outcome measurement and intervention component.

Risk of bias assessment

The risk of bias of the individual studies included was independently assessed by two reviewers. Any disagreement on the risk of bias between reviewers was resolved by discussion and by a third reviewer when necessary. The risk of bias of the individual studies included was assessed using the Academy of Nutrition and Dietetics, Quality Criteria Checklist [29]. The 10 questions focus on (1) how clear the research question was; (2) selection of participants; (3) randomization/ group comparability; (4) description of withdrawals; (5) how the blinding was; (6) whether study procedures were described clearly; (7) whether the outcomes were clearly defined; (8) were appropriate statistical analyses applied; (9) did the results support the conclusion; (10) funding or sponsorship bias. To be rated positive, each of the criteria 2, 3, 6 and 7 must be met and the majority of 10 criteria overall. Any of criteria 2, 3, 6 and 7 not being met resulted in a neutral rating. If most criteria (i.e., more than 6 of them) were not met, the article would have a negative rating.

Result

The search from literature yielded a total of 10,836 potentially relevant articles from 5 databases (Fig. 1). After removing duplicates, 4,914 records remained. Those articles were screened for title and abstract for eligibility, resulting in 4,737 records being excluded. The full text of the remaining 177 records was assessed and examined. Using the same criteria, a total of 142 records were excluded. Thus, a total of 35 records were included in this review.

Fig. 1
figure 1

Flowchart of identification and selection of studies in accordance with PRISMA guidelines

Study characteristics

In total, 25,726 school children recruited from 341 schools and 8 nursery centres from 12 different countries were included in this review. Most of the studies were mainly reported from the populations of the United States (n = 18). Six studies were conducted in low- and middle-income countries (LMICs) (Nepal, Bhutan, Burkina Faso and Brazil) and 29 studies were conducted in developed countries (United States, Australia, United Kingdom, Portugal, Canada, South Korea, Netherlands and Belgium). Sample size ranged from 1 to 49 schools and 44 to 4300 participants, with more than 80% of the included studies recruited more than 100 participants (n = 29/35). Participants’ age ranged from 2 to 19 years old, with the majority from the age of 8–12 years old. Duration of intervention ranged from 6 weeks to 4 years (mean ± SD: 10 ± 11 months) and integrated school gardening intervention activities included outdoor or indoor classroom gardening (e.g., Earthbox gardening); harvesting lessons; cooking lessons and experimental kitchen activities utilising harvests; taste tests; nutrition-related education on food cultivation, healthy living skills, agriculture and nutrition science; physical education; healthy F&V snack program; poster, poem and nutrition and vegetable charts displays on school boards, meat-free Monday, using locally source produce in school meals and market days to sell produce from the garden and local farmers’ market visit. Outcomes of each study varied, but the majority primarily focused on the changes in children's KAP on food consumption (particularly F&V).

Quality appraisal of included studies

The quality appraisal of the studies included is reported in Fig. 2. Almost half of the studies included had a low risk of bias with the remaining rated unclear risk (neutral). No study included had a high risk of bias. Categories that were commonly rated as weak (e.g., with more than half of the studies rated a high risk of bias) were statistical analysis, blinding and withdrawal description. Most of the studies (n = 33/35) failed to apply appropriate statistical analysis, studies rated as low risk of bias in this category were able to address the confounding factors as well as the application of intention to treat analysis. Majority of the studies (n = 32/35) failed to describe the allocation concealment or blinding of researchers, participants, or data collectors. In addition, a large proportion of studies did not describe the method of handling withdrawals (n = 24/35), including the follow-up method and withdrawal reasons. Detailed quality appraisal of each study is reported in Supplementary Table 2.

Fig. 2
figure 2

Quality rating of included studies using the Quality Criteria Checklist from Academy of Nutrition and Dietetics

Description of the included studies

A total of 35 studies have been included, and the characteristics of each intervention study are reported in Table 1. There were 18 out of the 35 studies in which the intervention included parental involvement. In this review, level of parental involvement differed between studies, ranging from students gardening with parents; student and family cooking events; parent gardening, home gardening, maintenance of school garden, school visit invitation to receive a brief of school gardening project, end-of-programme celebration invitation, take-home materials (e.g., “Family Stories” booklet and recipe cards) and parent newsletter (considered as weak parental component or low activity intensity). The main findings of the impacts of SGBP on intervention outcomes and the study quality are reported in Table 2.

Table 1 Summary of the included SGBP interventions (n = 35)
Table 2 Summary on the main findings of each SGBP intervention (n = 35)

Major findings

The impacts of school garden-based programmes with or without parental involvement on the children’s diet and nutritional-related knowledge, attitudes, and practices from the 35 studies included are summarised in Fig. 3. Non-significant increase is regarded as no change in terms of the effectiveness on improving the measure outcomes as reported by the studies.

Fig. 3
figure 3

Impacts of school garden-based programmes on measured outcomes between those with and without parental involvement (n = 35). *Refers to food, nutrition, gardening and science-related knowledge. ** Attitudes include the concepts of preference and/ or taste ratings towards. *** Others include fibre, vitamin A & C, salts, sugary sweetened beverages and ultra-processed foods reduction

Dietary practices and food consumption

Children’s F&V intake was the most studied outcome (n = 26). Six out of 10 studies demonstrated SGBP without parental involvement, with a shorter intervention duration ranging from 12 weeks to 28 weeks and a smaller sample size ranging from 77 to 320 participants, resulting in a more favourable outcome on children’s vegetable intake, especially among the younger children from pre-schools and primary schools [22, 32, 37, 47, 57, 59]. Contrarily, most of the SGBP with parental involvement did not show significant improvement in children’s vegetable intake (n = 11/16) [26, 31, 35, 38, 40, 44, 45, 52, 54,55,56]. However, this may be due to the longer intervention duration ranging from 1 year to 4 years, larger sample size ranging from 89 to 4300 participants or intervening at an older age (e.g., secondary school-aged children). Similar findings were observed in children’s fruit intake, SGBP with a shorter duration (~ 12 weeks) and smaller sample size (~ 77 to 99 participants) showed better improvement in children’s fruit intake among the preschool and primary school-aged children [47, 59]. However, the majority of the SGBP with longer intervention duration (~ 1 year to 4 years) and larger sample size (~ 60 to 4300 participants), did not observe significant improvement in children’s fruit intake, regardless of the parental involvement [3, 26, 27, 30, 31, 36, 38, 40, 42, 44, 45, 52, 54,55,56].

Four studies reported the positive impacts of SGBP on dietary fibre, and a study showed increased intake on vitamin A and vitamin C at the post-intervention [37, 44, 55, 59]. A study conducted on the Portuguese population showed a promising effect of SGBP in reducing students’ salt intake [51], and the other three studies found no significant improvement in reducing sugar-sweetened beverages (SSB) and ultra-processed food consumption at the post-intervention [30, 38, 49]. In addition, a small number of studies investigated the impact on the variety of fruits (n = 6) and vegetables (n = 7) consumed, with the majority not able to demonstrate a significant improvement (n = 5/6 [26, 27, 40, 42, 48]; n = 4/7 [26, 27, 40, 48], respectively).

Nutrition, gardening, agricultural and science-related knowledge

Nutrition, gardening, agricultural and science-related knowledge was the second most studied outcome (n = 20). Fourteen out of 20 studies reported that SGBP with or without parental involvement demonstrated significant improvement in children’s nutritional knowledge at the post-intervention, especially those shorter SGBP interventions (less than a year) integrating with classroom education and intervening at a younger age (6 to 15 years old) [3, 22, 26, 32, 35, 39,40,41, 46, 49, 50, 56,57,58]. It is worth highlighting that high sample size variability has been observed in those studies that have reported changes in children’s nutritional knowledge.

Attitudes and behaviours towards fruits and vegetables

Two thirds of the reported studies showed significant improvement in children’s attitudes and behaviours towards vegetables at post-intervention (n = 13/19) [22, 26, 27, 32, 33, 35, 41, 47, 49, 52, 56,57,58]. Parental involvement in SGBP seems to produce better improvement in children’s attitudes towards vegetables, especially those with shorter intervention duration ranging from 12 weeks to 1 year, regardless of the sample size and the children’s age group (n = 7/9) [26, 27, 33, 35, 49, 52, 56]. Similar findings were observed on children’s attitudes towards fruits, the majority of the SGBP with parental involvement reported improvement on children’s attitudes towards fruits (n = 3/5) [26, 27, 52] compared to those without parental involvement (n = 3/7) [21, 47, 57]. In addition, parental involvement in SBGP seems to exert beneficial effects on improving children’s willingness to consume F&V, especially when intervened at a younger age (aged 3–12 years old) with an intervention duration ranging from 8 weeks to 2.5 years (n = 4/6) [48, 52, 54, 56].

Other outcomes of interest

Four studies reported on the dietary self-efficacy in children, which refers to children’s self-belief in their food knowledge level and the self-confidence to purchase, plan, prepare and cook food, as well as to make appropriate food decisions to achieve higher nutritional value [60]. Most of the studies reported no significant improvement in dietary self-efficacy (n = 3/4) [39, 46, 58].

Eight studies reported the impact of SGBP on home F&V availability and consumption [21, 22, 34, 35, 43, 45, 48, 49]. Only one study from the US reported positive findings on home vegetable availability, with the remaining failing to demonstrate significant improvement [43]. In addition, one study from the US investigated the effect on school F&V availability reported a positive finding on improving school F&V availability [3].

Discussion

Are SGBP effective in improving diet-related knowledge, attitudes and practices among school children?

Despite the proposal of the knowledge, attitudes and behaviour communication model by Contento et al., 1992 which suggested a linear positive association between the three components that potentially influence the “practice” of such behaviour, recent research argued that such a relationship is far more reciprocal and dynamic [61, 62]. It is thus essential to understand the impacts of SGBP in addressing such association to maximise its intervention effect towards improving children F&V intake to alleviate childhood malnutrition. In this review, the findings generated from the 35 studies included indicated that school garden-based programmes were effective in increasing diet and nutritional knowledge, as well as promoting positive attitudes and behaviours (acceptability) towards vegetables among the school children, however, most of the studies reported no significant in their dietary practices such as F&V consumption and dietary diversity.

Positive impacts on food, nutrition, gardening and science-related knowledge

In this review, SGBP have shown promising effects in improving children’s knowledge of food, nutrition, gardening and science (Fig. 2). Acquisition of knowledge is the basis for behavioural change [63]. Active participation in school gardening activities in combination with in-class food and nutrition curriculum has strengthened not only children’s horticulture skills but also children’s declarative knowledge (what is a healthy diet), procedural knowledge (how to achieve a healthy diet) and conditional knowledge (when and why healthy diet) [41, 61, 64]. Children thus have a higher potential and ability to make better and healthier food choices. In addition, children have demonstrated a greater ability to identify unfamiliar food, as less typical vegetables are intentionally emphasized in class during the intervention and incorporated into cooking activities and recipes [37]. The “seed to mouth” nature of the cooking and gardening programme, where children eat what they have grown in the school garden, also explains why children are more likely to recognize the types of crop they have consumed [37].

Positive impacts on promoting attitudes and acceptability towards foods

SGBP may encourage children’s attitudes and acceptability to consume new food and reduce food neophobia via increasing their F&V exposure. Food neophobia refers to the reluctance to eat and try novel food, which often acts as a barrier to promote F&V preference and consumption among children and contribute to the development of unhealthful food habits [65,66,67]. In this review, SGBP were successful in improving children’s willingness to consume F&V. The direct involvements in growing and cooking own garden produces were associated with an increase in children self-reported willingness to consume new food [52, 56]. Additionally, the nature of the kitchen gardening programme, where children are encouraged to freely taste and share self-prepared meals with each other during kitchen class with no pressure to eat, has created a favourable social environment for children to try unfamiliar food and potentially reduce their food neophobic rate. A study conducted by Morgan et al., 2010 highlighted an increase in willingness and preference towards vegetables not only in the vegetables grown in the school garden, but also those in general, suggesting the intervention was successful in exerting influence beyond scope of the school garden, and even extended to those children did not directly expose to [56].

Interestingly, improvements were observed in children’s attitudes and acceptability towards vegetables, but not for the fruits. Previous evidence suggested that being actively involved in the food production and preparation process may exert positive influences on foods that are particularly hard to change preference towards [68, 69]. The hands-on learning experience provided by SGBP offers children regular positive exposure to vegetables. Through direct experience, for instance, crops growing, harvesting as well as food preparation, children increase familiarity with vegetables, and thus more likely to positively accept and improve taste preference towards such food [70,71,72]. This might also explain the insignificant intervention effect on improving children’s attitude towards fruits as the crops grown in the interventions were dominated by vegetable species, children thus had comparatively fewer opportunities to interact with fruits and thus lowering the chance to increase their acceptability towards such food.

Limited impacts on dietary practices and food consumption

Intervention effects on improving F&V dietary intake remain inconclusive due to the mixed results generated from the studies. F&V knowledge is one of the most important determinants of their consumption [46, 73,74,75,76]. This is also supported by the social cognitive theory as augmentation in food- and nutrition-related knowledge with the acquisition of horticultural skills could increase the behavioural capacity regarding F&V intake [60, 77]. Knowledge, attitudes, taste preferences and acceptability are often being described as one of the strongest predictors for future F&V intake [21, 37, 46]. However, in this review, our finding demonstrated that SGBPs improvement in such predictors may not be sufficient to translate into an actual increase in F&V uptake.

The weak intervention effect on dietary practices found in this review denotes SGBP might fail to address other determinants that might exert a greater influence on children’s F&V consumption. This includes school and home F&V availability, parental food habits and feeding practices, the level of perceived behaviour control (e.g., ease of increasing F&V intake) and dietary self-efficacy level (i.e., self-confidence in being able to increase F&V intake) among individuals, as well as the peers’ influences [78]. Children spend most of the time learning and working as a team at school, they are more likely to follow the group perspective and consider less about their own attitudes and beliefs [79]. In other words, when the peers are more health-conscious, individuals are more likely to consume more healthy food such as F&V regardless of their own attitude towards such foods [79, 80].

Nonetheless, studies with positive findings on improving dietary practice found that SGBP was helpful in building a “personal connection” between children and the crops they have grown through direct experience on crop planting and nurturing. The “garden-grown” nature also adds an extra value to the F&V, children are thus more inclined to try and consume those healthful foods [37, 58]. An increase in school F&V availability during intervention also acts as a drive-in promoting children’s F&V consumption [22]. Moreover, SGBP can exert its influence beyond the school setting, as it is found higher varieties of vegetables not cultivated from the school garden were consumed [22]. However, the studies with positive findings may be prone to bias. For instance, the study conducted by Parmer et al., 2009 may be prone to gender bias as it was conducted predominantly in males [57]. Previous studies reported gender differences in F&V intake with the female being more likely to consume F&V and have greater perceived behavioral control and favorable attitudes towards F&V [81,82,83,84]. The positive result from McAleese et al., 2007 might be prone to measurement error, as a one-time 24-hour food recall was used [59]. The use of one-time 24-hour recall to capture food intake might fail to obtain representable data due to the varied eating habits among individuals [26, 27]. Improvements in vegetable consumption observed from Ratcliffe et al., 2011 and McAleese et al., 2007 were mainly due to the reduced intake in the control group, thus implying a small improvement in the intervention group [22, 59].

Other measure outcomes – home food environment

In this review, there was a small number of studies that investigated the intervention impact on children’s home F&V availability (n = 6) and consumption (n = 2). Home F&V availability is known to be a crucial determinant in affecting children’s food choices. If F&V is not readily available at home, it is difficult for the children to transfer what they have learnt from the intervention into everyday life [26, 27]. However, most of the studies reported no significant impacts of SGBP on home F&V availability and consumption. The potential explanations account for the neutral effect of SGBP in modifying children’s home F&V consumption include an increase in age (lessoning effect on parental influences), family influences, unappealing presentation of F&V in home meal, low home food security, comparatively higher cost of F&V, limited accessibility to F&V within community and media influences [73, 85, 86]. With respect to home F&V availability, the authors speculated that the failure of increasing the home F&V availability may be due to the low parental participation or response rate, which subsequently hinders the children’s F&V uptake at home, as parents remain to be the main nutrition gatekeeper [35]. Since children spend a significant amount of time at home, they are more likely to enjoy and consume food that their parents enjoy, or vice versa, and prefer foods that are readily accessible and available in the home environment. Thus, it is important to improve parents’ KAP on diet and nutrition as well as the home F&V availability and accessibility to improve children’s food choices. Besides, it may be due to other determinants such as socioeconomic status and cultural influences, as well as the accessibility and availability of such foods within the neighbourhood [87,88,89].

The type, the extent and the length of SGBP towards the intervention success

SGBP components

The nature of SGBP plays a key role in determining the success of the intervention. It is observed that all SGBP included in this review provided hand-on gardening experience, with most offered alongside nutrition education (n = 30), and cooking lessons (n = 16), which were shown to be effective in improving children’s knowledge, attitudes, and acceptability towards healthy eating practises. It is worth mentioning nutrition education is a crucial component in SGBP to improve children’s nutrition, gardening and agricultural knowledge as 12 out of 14 successful studies have integrated classroom education as part of SGBP. Other activities, including tasting sessions (n = 3), local farmers’ market visit (n = 3), local farmers and community members participating in gardening (n = 1), locally sourced produce included in school meals (n = 1) and other promotional activities such as poster display (n = 2), nutrition handout distribution (n = 1), healthy F&V snack programme (n = 1), Carrot camp (n = 1), harvest of the month (n = 1), meat-free Monday section (n = 1) and take-home activities (n = 1), were also investigated in some studies with unclear additional effect on improving children’s KAP. The effectiveness and the need for such components are thus questionable and worth to be further investigated. This study also investigated the effects of specialist/trained teacher delivered SGBP on improving intervention outcomes with no significant result observed.

Length of intervention

Previous evidence has shown school gardening interventions that succeed in enhancing nutrition knowledge lasted for a minimum of 17 weeks [39]. This review, however, reveals a minimum of 9 to 10 weeks of intervention is sufficient to observe a significant improvement in nutritional knowledge among school children aged 10–12 years old, implying a shorter intervention is as effective as a longer intervention in improving in such outcome. Similar findings were observed in the outcomes of attitudes towards vegetables (12 weeks to 1 year) and F&V intake (F: 12 weeks; V:12–28 weeks). A possible explanation is those interventions with shorter duration might have more intense effect which may not be long-lasting when intervention period lengthens. In addition, interventions that succeed in reducing children food neophobic rate in this review were mostly conducted within 5 months to 1 year, implying short intervention favours the improvement in children’s food acceptability whereas long intervention might demotivate children and potentially reduce the intervention effect, as SGBP turns from initially a “novel experience” into a “mainstream activity” [90].

Age

Age is one of the crucial factors in determining the effectiveness of SGBP in improving children’s food choices and dietary behaviour. In this review, it is observed that the SGBP which have been intervened at an early age may produce more favourable outcomes in improving children’s nutrition-related knowledge, willingness to consume F&V and vegetable intake. Children’s food preferences and dietary habits are generally developed and shaped early in life and may persist in adulthood, thus early childhood provides an ideal opportunity to shape healthy eating behaviours among individuals [91]. Younger children tend to have more plasticity in preferences and are more likely to accept foods that are available within their environment, which may explain why SGBP have been reported to be more successful when targeting the younger population [92].

Sample size

Sample size is also one of the determinants of the intervention’s success. This review revealed that the SGBP conducted in a smaller sample size produced more favourable outcomes in improving F&V intake, school interventions conducted in a smaller sample size often have a smaller teacher-student ratio with a higher teacher-student interaction, students thus receive more individualised attention and support with a higher potential to achieve better performance on intervention outcomes [93]. However, this finding was contradictory to most studies that support the usage of a larger sample size in intervention as it produces more representable, accurate and reliable results [94, 95]. Further studies are needed to explore and consolidate the relationship between sample size and intervention outcomes and understand the underlined rationale behind.

Does parent participation benefit the SGBP?

This review reveals that parental involvement in SGBP may help to better promote children’s attitudes towards and willingness to consume F&V. Parents are known to play a fundamental role in the development and achievement of the children [96]. According to social learning theory, children learn and model from the behaviour of others through observation [97]. As children spend a substantial amount of time with parents, children’s food choice, eating behaviour and eating-related attitudes are thus hugely influenced by their parent [92, 98, 99]. Active and effective parental involvement in the SGBP, including face-to-face engagement with frequent interactions with children, provides parents more opportunities to impose positive parental modelling effects on healthy eating and enjoyment of eating F&V. Children are thus more likely to develop a preference for F&V and to make healthier food choices.

The insignificant parental effect observed in most of the studies could possibly be due to the little parental involvement element and low parents’ participation in the intervention activities. Studies conducted by Jaenke et al., 2012, Lee et al., 2017, Taylor et al., 2018, and Massarani et al., 2019 only included regular parent newsletter distribution as their main parents’ engagement activities, as newsletter could only serve as an informed purpose, parent-children’s interactions were hence limited [38, 42, 45, 54]. In addition, parents often have inflexible and overwhelming work schedules with multiple responsibilities in charge, resulting in limited time dedicated to each responsibility and hence a low parents’ participation in school activities is expected [100, 101]. Therefore, it is understandable that no significant parental effect was observed. Moreover, some of the studies did not describe the parental involvement activities in detail (e.g., the number of parents involved, and the response rate were absent), which make it difficult to assess its impacts on the effectiveness of the interventions. Future SGBP, hence, should measure the degree of parental engagement, if possible, examine what constitutes effective parental involvement and identify effective strategies to promote and maximise parental interaction with children during the intervention. To encourage more parental engagement, it requires better cooperation between the school and parents. It is suggested to schedule meetings and activities on multiple occasions to match parents’ varying schedules and be flexible in accommodating parents and families in the school programmes such as providing incentives, food or refreshments, and free transportation to minimise barriers and create an enabling environment for parents’ participation [102].

SGBP in developed countries and LMICs

Six studies included from LMICs observed, similar to the overall findings or findings in developed countries, significant improvements in children’s preferences and attitudes towards vegetables but no significant improvement in F&V intake. Whilst improvement in food, nutrition, gardening and science-related knowledge was observed in the developed countries, it was not observed in the LMICs. The insignificant gardening effects on improving children’s knowledge and F&V consumption could be due to the inadequacy in school resources. Due to the limited number of teachers and fewer classroom materials provided, teachers from LMICs are already struggling with completing their high amount of workload. Schreinemachers et al., 2019 reported that teaching in Burkina Faso is difficult as every teacher is averagely responsible for 45 primary schoolchildren, requesting them to take on extra responsibilities and time for the implementation of an unessential gardening intervention are thus extremely hard [40]. The intervention effects might consequently be undermined as teachers are less likely to deliver the intervention programme due to the constraints of time and resources. Furthermore, the seasonal supply of vegetables also lowers the intervention effect. Due to the limited water supply in the dry season, vegetables are reported to be available for only 3 to 4 months, effect on improving children’s preference towards and intake of F&V are therefore reduced due to the limited availability and accessibility of F&V [40]. Besides, it is known that most school children from LMICs already participated in agricultural activities at home, garden-based intervention might be more appealing to those from developed countries where children lack nature experience and outdoor activities at school [40]. The parental influences on shaping children’s dietary behaviour were weak in the six studies, which is possibly due to their comparatively low education level [26, 33]. With limited knowledge and awareness of nutrition and healthy diet, parents from LMICs might be less likely to make healthier food choices for their children, family modelling impact is thus reduced.

Strengths and limitations

One of the strengths of this review is that a comprehensive literature search was performed from five different databases to adequately identify most of the literature related to this topic, and potentially reduced the selection bias [103]. A robust review method was used, as two reviewers were involved to determine the inclusion and exclusion of studies independently. In addition, based on the Quality Criteria Checklist from the Academy of Nutrition and Dietetics (2016), none of the included studies was rated as high risk of bias, this demonstrates the high quality of the included studies.

There are a few limitations that cannot be ignored. The use of various measurement tools to assess the outcome measures increases the complexity of interpretation when comparing between studies. Heterogeneity of the intervention components, sample sizes, study designs and outcome measures between studies implied that the synthesis of the meta-analysis was not possible. Therefore, a single summary estimate of the impacts of SGBP failed to be generated [104]. In addition, result in this review is just a general sum up of findings from each study reported, age, sample size, ethnicity and study quality have not been weighted. Impacts of society-led or community-led gardening programmes have also not been explored and discussed, thus it is beyond the remit of this review to fully cover the impact and efficiency of society or community-led gardening programmes, a recent review by Ohly et al., 2016 provides a comprehensive overview of this topic [105]. Moreover, all SGBPs included were multifaceted with varying degrees of cooking, gardening, and nutrition components. It is thus difficult to assess which aspect of these components and how intense (or what dose) these components were most likely to be associated with positive outcomes on children’s diet and nutrition related KAP. Besides, most of the SGBP did not consider the variation of teacher experience and motivation, which are some of the determinants for programme effectiveness. The use of varying teaching approaches and enthusiasm in curriculum delivery may influence students’ learning outcomes, and potentially determine the success of the intervention [54, 106]. In addition, the review might be prone to selection bias as only studies written in English were included. Furthermore, evidence was based on studies in which the participants were predominantly US and European populations with only a small amount from Asian or other countries, therefore the findings generated may not be generalizable and transferable to the other populations.

Recommendations on future SGBP

To strengthen the impact of SGBP in promoting children’s KAP as observed from most of the successful interventions, integrated SGBP which include multiple or additional components such as nutritional education and parental involvement activities are encouraged to maximise the intervention effect. Classroom education is a crucial aspect of SGBP to effectively improve children’s nutritional-related knowledge. Thus, future SGBP is highly recommended to integrate with age-appropriate classroom education, conduct in smaller sample size with smaller child-to-staff ratio and shorter duration (~ 12 to 28 weeks), and intervene at an early age, preferably around the pre-school and primary school age, to achieve better outcomes on children’s nutritional-related knowledge and F&V consumption [107]. In addition, parental involvement in SGBP may help to promote children’s attitudes towards F&V, which may subsequently promote the intake of such foods.

Future SGBP should also adopt a multi-level approach, which covers the school, home and community environment to maximise the scope and therefore the impact of intervention. In addition, to further promote F&V consumption among children at school, it is recommended to incorporate food service into SGBP intervention. Potential ways include setting up a school salad bar in the cafeteria using the crops grown from SGBP or utilizing the produces to supplement the food in the cafeteria to increase the accessibility and availability of F&V at school. Future SGBP should also consider building relationships or partnerships with the local farmers or community gardens or, promoting or providing the students and their families the locally grown produce so as to maximise the exposure to F&V and the potential to promote such intake. Future studies should investigate the effective strategies to improve parental participation and involvement to strengthen the impact of SGBP in improving F&V consumption. In addition, it is essential for parents to acknowledge their key roles in shaping children’s eating habits. Future SGBP should offer more parental lessons and provide parents with the knowledge and tools to improve children’s eating behaviours [108]. This includes 1) offering practical advice on fostering children’s preferences towards healthier food options and increasing their willingness to consume unfamiliar food; 2) understanding the negative impact of coercive feeding practice and providing alternative options; 3) helping parents to establish a good parental role model; 4) educating the importance of not overfeeding their children and not forcing them to finish the meal when full [108]. Furthermore, more focus should be placed on investigating the long-term impact and the sustainability of the future SGBP.

Conclusion

School garden-based programmes have generally shown beneficial effects on children’s knowledge of diet and nutrition, attitudes and acceptability towards vegetables with limited influence shown on dietary practices including the actual consumption of fruits and vegetables and the diversity of the diets. Impacts of SGBP on measured outcomes were highly influenced by various social and environmental factors with it being shown to be more effective when conducted at a younger age, for instance, in pre- or primary school-age children. In addition, positive outcomes found in children’s nutritional knowledge and dietary practices when conducted in a shorter intervention duration, and smaller sample size or smaller child-to-staff ratio, were possibly due to being more focused and accurately measured. Nevertheless, large heterogeneity was observed in the study design and methodologies, which have weakened the outcome significancy analysis. Parental involvement may help to better promote children’s attitudes, behaviours and willingness to consume fruits and vegetables. More measures are needed to be taken to encourage parental engagement so as to maximise the intervention effect. Future SGBP is suggested to use a combined multidisciplinary and multi-level approach targeting the children, parents and community to effectively promote healthy eating among the children and prevent childhood obesity. This would ensure that the interventions tackle individual intake as well as the factors affecting the social, family and school environment.

Availability of data and materials

The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

Abbreviations

F&V:

Fruits and vegetables

KAP:

Knowledge, attitudes, and practices

SGBP:

School garden-based programme(s)

UK:

United Kingdom

US:

United States

WHO:

World Health Organization

References

  1. Popkin BM, Corvalan C, Grummer-Strawn LM. Dynamics of the double burden of malnutrition and the changing nutrition reality. Lancet. 2020;395(10217):65–74.

    PubMed  Article  Google Scholar 

  2. Abarca-Gómez L, Abdeen ZA, Hamid ZA, Abu-Rmeileh NM, Acosta-Cazares B, Acuin C, et al. Worldwide trends in body-mass index, underweight, overweight, and obesity from 1975 to 2016: a pooled analysis of 2416 population-based measurement studies in 128· 9 million children, adolescents, and adults. Lancet. 2017;390(10113):2627–42.

    Article  Google Scholar 

  3. Yoder ABB, Liebhart JL, McCarty DJ, Meinen A, Schoeller D, Vargas C, et al. Farm to elementary school programming increases access to fruits and vegetables and increases their consumption among those with low intake. J Nutr Educ Behav. 2014;46(5):341–9.

    Article  Google Scholar 

  4. World Cancer Research Fund. Diet, nutrition, physical activity and Cancer: a global perspective. A summary of the third expert report. 2012. Retrieved from https://www.wcrf.org/wp-content/uploads/2021/02/Summary-of-Third-Expert-Report-2018.pdf.

  5. World Health Organization. Healthy diet – Fact sheets. 2020. Retrieved from https://www.who.int/news-room/fact-sheets/detail/healthy-diet

  6. Howarth NC, Saltzman E, Roberts SB. Dietary fiber and weight regulation. Nutr Rev. 2001;59(5):129–39.

    CAS  PubMed  Article  Google Scholar 

  7. Rasmussen M, Krølner R, Klepp K-I, Lytle L, Brug J, Bere E, et al. Determinants of fruit and vegetable consumption among children and adolescents: a review of the literature. Part I: quantitative studies. Int J Behav Nutr Phys Act. 2006;3(1):1–19.

    Article  Google Scholar 

  8. Ventura E, Davis J, Byrd-Williams C, Alexander K, McClain A, Lane CJ, et al. Reduction in risk factors for type 2 diabetes mellitus in response to a low-sugar, high-fiber dietary intervention in overweight Latino adolescents. Arch Pediatr Adolesc Med. 2009;163(4):320–7.

    PubMed  Article  Google Scholar 

  9. Ventura EE, Davis JN, Alexander KE, Shaibi GQ, Lee W, Byrd-Williams CE, et al. Dietary intake and the metabolic syndrome in overweight Latino children. J Am Diet Assoc. 2008;108(8):1355–9.

    CAS  PubMed  PubMed Central  Article  Google Scholar 

  10. Miller SJ, Batra A, Shearrer G, House B, Cook L, Pont S, et al. Dietary fibre linked to decreased inflammation in overweight minority youth. Pediatric Obesity. 2016;11(1):33–9.

    CAS  PubMed  Article  Google Scholar 

  11. Lynch C, Kristjansdottir AG, Te Velde SJ, Lien N, Roos E, Thorsdottir I, et al. Fruit and vegetable consumption in a sample of 11-year-old children in ten European countries–the PRO GREENS cross-sectional survey. Public Health Nutr. 2014;17(11):2436–44.

    PubMed  Article  Google Scholar 

  12. Green L, Kreuter M. The precede–proceed model. Health promotion planning: an educational approach. 3rd ed. Mountain View (CA): Mayfield Publishing Company; 1999. p. 32–43.

    Google Scholar 

  13. Bere E, Klepp K-I. Changes in accessibility and preferences predict children's future fruit and vegetable intake. Int J Behav Nutr Phys Act. 2005;2(1):1–8.

    Article  Google Scholar 

  14. Birch L, Savage JS, Ventura A. Influences on the development of children's eating behaviours: from infancy to adolescence. Can J Dietetic Pract Res. 2007;68(1):s1.

    Google Scholar 

  15. Ventura AK, Worobey J. Early influences on the development of food preferences. Curr Biol. 2013;23(9):R401–8.

    CAS  PubMed  Article  Google Scholar 

  16. Fitzgerald A, Heary C, Nixon E, Kelly C. Factors influencing the food choices of Irish children and adolescents: a qualitative investigation. Health Promot Int. 2010;25(3):289–98.

    PubMed  Article  Google Scholar 

  17. Singer MR, Moore LL, Garrahie EJ, Ellison RC. The tracking of nutrient intake in young children: the Framingham Children's study. Am J Public Health. 1995;85(12):1673–7.

    CAS  PubMed  PubMed Central  Article  Google Scholar 

  18. Resnicow K, Davis-Hearn M, Smith M, Baranowski T, Lin LS, Baranowski J, et al. Social-cognitive predictors of fruit and vegetable intake in children. Health Psychol. 1997;16(3):272.

    CAS  PubMed  Article  Google Scholar 

  19. Skinner JD, Carruth BR, Bounds W, Ziegler PJ. Children's food preferences: a longitudinal analysis. J Am Diet Assoc. 2002;102(11):1638–47.

    PubMed  Article  Google Scholar 

  20. Thompson VJ, Bachman CM, Baranowski T, Cullen KW. Self-efficacy and norm measures for lunch fruit and vegetable consumption are reliable and valid among fifth grade students. J Nutr Educ Behav. 2007;39(1):2–7.

    PubMed  PubMed Central  Article  Google Scholar 

  21. Hanbazaza MA, Triador L, Ball GD, Farmer A, Maximova K, Nation AF, et al. The impact of school gardening on Cree children's knowledge and attitudes toward vegetables and fruit. Can J Diet Pract Res. 2015;76(3):133–9.

    PubMed  Article  Google Scholar 

  22. Ratcliffe MM, Merrigan KA, Rogers BL, Goldberg JP. The effects of school garden experiences on middle school-aged students’ knowledge, attitudes, and behaviors associated with vegetable consumption. Health Promot Pract. 2011;12(1):36–43.

    PubMed  Article  Google Scholar 

  23. Evans A, Ranjit N, Rutledge R, Medina J, Jennings R, Smiley A, et al. Exposure to multiple components of a garden-based intervention for middle school students increases fruit and vegetable consumption. Health Promot Pract. 2012;13(5):608–16.

    PubMed  Article  Google Scholar 

  24. Story M, Kaphingst KM, Robinson-O'Brien R, Glanz K. Creating healthy food and eating environments: policy and environmental approaches. Annu Rev Public Health. 2008;29:253–72.

    PubMed  Article  Google Scholar 

  25. Christian MS, Evans CE, Nykjaer C, Hancock N, Cade JE. Evaluation of the impact of a school gardening intervention on children’s fruit and vegetable intake: a randomised controlled trial. Int J Behav Nutr Phys Act 2014;11(1):1–15.

  26. Schreinemachers P, Bhattarai DR, Subedi GD, Acharya TP, Chen H-p, Yang R-y, et al. Impact of school gardens in Nepal: a cluster randomised controlled trial. J Dev Effectiveness. 2017;9(3):329–43.

    Article  Google Scholar 

  27. Schreinemachers P, Rai BB, Dorji D, Chen H-p, Dukpa T, Thinley N, et al. School gardening in Bhutan: evaluating outcomes and impact. Food Sec. 2017;9(3):635–48.

    Article  Google Scholar 

  28. Evans CE, Christian MS, Cleghorn CL, Greenwood DC, Cade JE. Systematic review and meta-analysis of school-based interventions to improve daily fruit and vegetable intake in children aged 5 to 12 y. Am J Clin Nutr. 2012;96(4):889–901.

    CAS  PubMed  Article  Google Scholar 

  29. Magistrelli A, Chezem JC. Effect of ground cinnamon on postprandial blood glucose concentration in normal-weight and obese adults. J Acad Nutr Diet. 2012;112:1806–9. https://doi.org/10.1016/j.jand.2012.07.037.

    CAS  Article  PubMed  Google Scholar 

  30. Davis JN, Pérez A, Asigbee FM, Landry MJ, Vandyousefi S, Ghaddar R, et al. School-based gardening, cooking and nutrition intervention increased vegetable intake but did not reduce BMI: Texas sprouts-a cluster randomized controlled trial. Int J Behav Nutr Phys Act. 2021;18(1):1–14.

    Article  Google Scholar 

  31. Barnard M, Mann G, Green E, Tkachuck E, Knight K. Evaluation of a comprehensive farm-to-school program: parent and teacher perspectives. J Hunger Environ Nutr. 2020;15(6):794–808.

    Article  Google Scholar 

  32. Kim S-O, Park S. Garden-based integrated intervention for improving children’s eating behavior for vegetables. Int J Environ Res Public Health. 2020;17(4):1257.

    Article  Google Scholar 

  33. Schreinemachers P, Baliki G, Shrestha RM, Bhattarai DR, Gautam IP, Ghimire PL, et al. Nudging children toward healthier food choices: an experiment combining school and home gardens. Global Food Security. 2020;26:100454.

    PubMed  Article  Google Scholar 

  34. Shrestha A, Schindler C, Odermatt P, Gerold J, Erismann S, Sharma S, et al. Nutritional and health status of children 15 months after integrated school garden, nutrition, and water, sanitation and hygiene interventions: a cluster-randomised controlled trial in Nepal. BMC Public Health. 2020;20(1):1–19.

    Article  CAS  Google Scholar 

  35. van den Berg A, Warren JL, McIntosh A, Hoelscher D, Ory MG, Jovanovic C, et al. Impact of a gardening and physical activity intervention in title 1 schools: the TGEG study. Child Obes. 2020;16(Suppl 1):44–54.

    Article  Google Scholar 

  36. Khan M, Bell R. Effects of a school based intervention on Children’s physical activity and healthy eating: a mixed-methods study. Int J Environ Res Public Health. 2019;16(22):4320.

    Article  Google Scholar 

  37. Landry MJ, Markowitz AK, Asigbee FM, Gatto NM, Spruijt-Metz D, Davis JN. Cooking and gardening behaviors and improvements in dietary intake in Hispanic/Latino youth. Child Obes. 2019;15(4):262–70.

    PubMed  Article  Google Scholar 

  38. Massarani FA, Citelli M, Canella DS, Koury JC. Healthy eating promoting in a Brazilian sports-oriented school: a pilot study. PeerJ. 2019;7:e7601.

    PubMed  Article  Google Scholar 

  39. Huys N, Cardon G, De Craemer M, Hermans N, Renard S, Roesbeke M, et al. Effect and process evaluation of a real-world school garden program on vegetable consumption and its determinants in primary schoolchildren. PLoS One. 2019;14(3):e0214320.

    CAS  PubMed  Article  Google Scholar 

  40. Schreinemachers P, Ouedraogo MS, Diagbouga S, Thiombiano A, Kouamé SR, Sobgui CM, et al. Impact of school gardens and complementary nutrition education in Burkina Faso. J Dev Effectiveness. 2019;11(2):132–45.

    Article  Google Scholar 

  41. Leuven JR, RUtenfrans AH, Dolfing AG, Leuven RS. School gardening increases knowledge of primary school children on edible plants and preference for vegetables. Food Sci Nutr. 2018;6(7):1960–7.

    PubMed  PubMed Central  Article  Google Scholar 

  42. Taylor JC, Zidenberg-Cherr S, Linnell JD, Feenstra G, Scherr RE. Impact of a multicomponent, school-based nutrition intervention on students’ lunchtime fruit and vegetable availability and intake: a pilot study evaluating the shaping healthy choices program. J Hunger Environ Nutr. 2018;13(3):415–28.

    Article  Google Scholar 

  43. Wells NM, Meyers BM, Todd LE, Henderson CR Jr, Barale K, Gaolach B, et al. The carry-over effects of school gardens on fruit and vegetable availability at home: a randomized controlled trial with low-income elementary schools. Prev Med. 2018;112:152–9.

    PubMed  Article  Google Scholar 

  44. Gatto NM, Martinez LC, Spruijt-Metz D, Davis JN. LA sprouts randomized controlled nutrition, cooking and gardening programme reduces obesity and metabolic risk in Hispanic/Latino youth. Pediatric Obesity. 2017;12(1):28–37.

    CAS  PubMed  Article  Google Scholar 

  45. Lee RE, Parker NH, Soltero EG, Ledoux TA, Mama SK, McNeill L. Sustainability via active garden education (SAGE): results from two feasibility pilot studies. BMC Public Health. 2017;17(1):1–11.

    Article  Google Scholar 

  46. Davis JN, Martinez LC, Spruijt-Metz D, Gatto NM. LA Sprouts: A 12-week gardening, nutrition, and cooking randomized control trial improves determinants of dietary behaviors. J Nutr Educ Behav 2016;48(1):2–11. e11.

  47. Duncan MJ, Eyre E, Bryant E, Clarke N, Birch S, Staples V, et al. The impact of a school-based gardening intervention on intentions and behaviour related to fruit and vegetable consumption in children. J Health Psychol. 2015;20(6):765–73.

    PubMed  Article  Google Scholar 

  48. Sharma SV, Hedberg AM, Skala KA, Chuang R-J, Lewis T. Feasibility and acceptability of a gardening-based nutrition education program in preschoolers from low-income, minority populations. J Early Child Res. 2015;13(1):93–110.

    Article  Google Scholar 

  49. Spears-Lanoix EC, McKyer ELJ, Evans A, McIntosh WA, Ory M, Whittlesey L, et al. Using family-focused garden, nutrition, and physical activity programs to reduce childhood obesity: the Texas! Go! Eat! Grow! Pilot study. Child Obes. 2015;11(6):707–14.

    PubMed  Article  Google Scholar 

  50. Wells NM, Myers BM, Todd LE, Barale K, Gaolach B, Ferenz G, et al. The effects of school gardens on children's science knowledge: a randomized controlled trial of low-income elementary schools. Int J Sci Educ. 2015;37(17):2858–78.

    Article  Google Scholar 

  51. Cotter J, Cotter MJ, Oliveira P, Cunha P, Polónia J. Salt intake in children 10–12 years old and its modification by active working practices in a school garden. J Hypertens. 2013;31(10):1966–71.

    CAS  PubMed  Article  Google Scholar 

  52. Gibbs L, Staiger PK, Johnson B, Block K, Macfarlane S, Gold L, et al. Expanding children’s food experiences: the impact of a school-based kitchen garden program. J Nutr Educ Behav. 2013;45(2):137–46.

    PubMed  Article  Google Scholar 

  53. Gatto NM, Ventura EE, Cook LT, Gyllenhammer LE, Davis JN. LA sprouts: a garden-based nutrition intervention pilot program influences motivation and preferences for fruits and vegetables in Latino youth. J Acad Nutr Diet. 2012;112(6):913–20.

    PubMed  Article  Google Scholar 

  54. Jaenke RL, Collins CE, Morgan PJ, Lubans DR, Saunders KL, Warren JM. The impact of a school garden and cooking program on boys’ and girls’ fruit and vegetable preferences, taste rating, and intake. Health Educ Behav. 2012;39(2):131–41.

    PubMed  Article  Google Scholar 

  55. Davis JN, Ventura EE, Cook LT, Gyllenhammer LE, Gatto NM. LA sprouts: a gardening, nutrition, and cooking intervention for Latino youth improves diet and reduces obesity. J Am Diet Assoc. 2011;111(8):1224–30.

    PubMed  Article  Google Scholar 

  56. Morgan PJ, Warren JM, Lubans DR, Saunders KL, Quick GI, Collins CE. The impact of nutrition education with and without a school garden on knowledge, vegetable intake and preferences and quality of school life among primary-school students. Public Health Nutr. 2010;13(11):1931–40.

    PubMed  Article  Google Scholar 

  57. Parmer SM, Salisbury-Glennon J, Shannon D, Struempler B. School gardens: an experiential learning approach for a nutrition education program to increase fruit and vegetable knowledge, preference, and consumption among second-grade students. J Nutr Educ Behav. 2009;41(3):212–7.

    PubMed  Article  Google Scholar 

  58. Somerset S, Markwell K. Impact of a school-based food garden on attitudes and identification skills regarding vegetables and fruit: a 12-month intervention trial. Public Health Nutr. 2009;12(2):214–21.

    PubMed  Article  Google Scholar 

  59. McAleese JD, Rankin LL. Garden-based nutrition education affects fruit and vegetable consumption in sixth-grade adolescents. J Am Diet Assoc. 2007;107(4):662–5.

    CAS  PubMed  Article  Google Scholar 

  60. Bandura A, Freeman W, Lightsey R. Self-efficacy: the exercise of control: Springer; 1999.

    Google Scholar 

  61. Schrader P, Lawless KA. The knowledge, attitudes, & behaviors approach how to evaluate performance and learning in complex environments. Perform Improv. 2004;43(9):8–15.

    Article  Google Scholar 

  62. Contento IR, Manning AD, Shannon B. Research perspective on school-based nutrition education. J Nutr Educ. 1992;24(5):247–60.

    Article  Google Scholar 

  63. Rolling TE, Hong M. The effect of social cognitive theory-based interventions on dietary behavior within children. J Nutr Health Food Sci. 2016;4(5):1–9.

    Google Scholar 

  64. Berezowitz CK, Bontrager Yoder AB, Schoeller DA. School gardens enhance academic performance and dietary outcomes in children. J Sch Health. 2015;85(8):508–18.

    PubMed  Article  Google Scholar 

  65. Falciglia GA, Couch SC, Gribble LS, Pabst SM, Frank R. Food neophobia in childhood affects dietary variety. J Am Diet Assoc. 2000;100(12):1474–81.

    CAS  PubMed  Article  Google Scholar 

  66. Cooke L, Wardle J, Gibson E. Relationship between parental report of food neophobia and everyday food consumption in 2–6-year-old children. Appetite. 2003;41(2):205–6.

    CAS  PubMed  Article  Google Scholar 

  67. Russell CG, Worsley A. Why don’t they like that? And can I do anything about it? The nature and correlates of parents’ attributions and self-efficacy beliefs about preschool children’s food preferences. Appetite. 2013;66:34–43.

    PubMed  Article  Google Scholar 

  68. Juhl HJ, Poulsen CS. Antecedents and effects of consumer involvement in fish as a product group. Appetite. 2000;34(3):261–7.

    CAS  PubMed  Article  Google Scholar 

  69. Verbeke W, Vackier I. Individual determinants of fish consumption: application of the theory of planned behaviour. Appetite. 2005;44(1):67–82.

    PubMed  Article  Google Scholar 

  70. Morris J, Neustadter A, Zidenberg-Cherr S. First-grade gardeners more likely to taste vegetables. Calif Agric. 2001;55(1):43–6.

    Article  Google Scholar 

  71. Wardle J, Cooke LJ, Gibson EL, Sapochnik M, Sheiham A, Lawson M. Increasing children's acceptance of vegetables; a randomized trial of parent-led exposure. Appetite. 2003;40(2):155–62.

    PubMed  Article  Google Scholar 

  72. Lakkakula A, Geaghan J, Zanovec M, Pierce S, Tuuri G. Repeated taste exposure increases liking for vegetables by low-income elementary school children. Appetite. 2010;55(2):226–31.

    PubMed  Article  Google Scholar 

  73. Willows ND, Veugelers P, Raine K, Kuhle S. Prevalence and sociodemographic risk factors related to household food security in Aboriginal peoples in Canada. Public Health Nutr. 2009;12(8):1150–6.

    PubMed  Article  Google Scholar 

  74. Kristjansdottir AG, De Bourdeaudhuij I, Klepp K-I, Thorsdottir I. Children’s and parents’ perceptions of the determinants of children’s fruit and vegetable intake in a low-intake population. Public Health Nutr. 2009;12(8):1224–33.

    PubMed  Article  Google Scholar 

  75. Fischer C, Brug J, Tak NI, Yngve A, te Velde SJ. Differences in fruit and vegetable intake and their determinants among 11-year-old schoolchildren between 2003 and 2009. Int J Behav Nutr Phys Act. 2011;8(1):1–11.

    Article  Google Scholar 

  76. Grosso G, Mistretta A, Turconi G, Cena H, Roggi C, Galvano F. Nutrition knowledge and other determinants of food intake and lifestyle habits in children and young adolescents living in a rural area of Sicily, South Italy. Public Health Nutr. 2013;16(10):1827–36.

    PubMed  Article  Google Scholar 

  77. Glanz K, Rimer BK, Viswanath K. Health behavior and health education: theory, research, and practice: Wiley; 2008.

    Google Scholar 

  78. Smelser NJ, Baltes PB. International encyclopedia of the social & behavioral sciences. Amsterdam: Elsevier; 2001.

    Google Scholar 

  79. Frymier AB, Nadler MK. Persuasion: Integrating theory, research, and practice. Recording for the Blind & Dyslexic. 2007.

  80. Rogers R, Prentice-Dunn S, Gochman D. Handbook of health behavior research 1: personal and social determinants. New York: Plenum Press; 1997. p. 113–32.

    Google Scholar 

  81. Emanuel AS, McCully SN, Gallagher KM, Updegraff JA. Theory of planned behavior explains gender difference in fruit and vegetable consumption. Appetite. 2012;59(3):693–7.

    PubMed  PubMed Central  Article  Google Scholar 

  82. Cooke LJ, Wardle J. Age and gender differences in children's food preferences. Br J Nutr. 2005;93(5):741–6.

    CAS  PubMed  Article  Google Scholar 

  83. Macaux ALB. Eat to live or live to eat? Do parents and children agree? Public Health Nutr. 2001;4(1a):141–6.

    Article  Google Scholar 

  84. Reynolds KD, Baranowski T, Bishop DB, Farris RP, Binkley D, Nicklas TA, et al. Patterns in child and adolescent consumption of fruit and vegetables: effects of gender and ethnicity across four sites. J Am Coll Nutr. 1999;18(3):248–54.

    CAS  PubMed  Article  Google Scholar 

  85. Santiago-Torres M, Adams AK, Carrel AL, LaRowe TL, Schoeller DA. Home food availability, parental dietary intake, and familial eating habits influence the diet quality of urban Hispanic children. Child Obes. 2014;10(5):408–15.

    PubMed  PubMed Central  Article  Google Scholar 

  86. Findlay LC, Langlois KA, Kohen DE. Hunger among Inuit children in Canada. International Journal of Circumpolar Health. 2013;72(1):20324.

    Article  Google Scholar 

  87. Dubowitz T, Heron M, Bird CE, Lurie N, Finch BK, Basurto-Dávila R, et al. Neighborhood socioeconomic status and fruit and vegetable intake among whites, blacks, and Mexican Americans in the United States. Am J Clin Nutr. 2008;87(6):1883–91.

    CAS  PubMed  Article  Google Scholar 

  88. Pollard J, Kirk SL, Cade JE. Factors affecting food choice in relation to fruit and vegetable intake: a review. Nutr Res Rev. 2002;15(2):373–87.

    CAS  PubMed  Article  Google Scholar 

  89. Jago R, Baranowski T, Baranowski JC. Fruit and vegetable availability: a micro environmental mediating variable? Public Health Nutr. 2007;10(7):681–9.

    PubMed  Article  Google Scholar 

  90. Davis JN, Spaniol MR, Somerset S. Sustenance and sustainability: maximizing the impact of school gardens on health outcomes. Public Health Nutr. 2015;18(13):2358–67.

    PubMed  Article  Google Scholar 

  91. Mennella JA, Castor SM. Sensitive period in flavour learning: effects of duration of exposure to formula flavors on food likes during infancy. Clin Nutr. 2012;31(6):1022–5.

    PubMed  PubMed Central  Article  Google Scholar 

  92. Birch LL, Fisher JO. Development of eating behaviours among children and adolescents. Pediatrics. 1998;101(suppl 2):539–49.

    CAS  PubMed  Article  Google Scholar 

  93. Koc N, Celik B. The impact of number of students per teacher on student achievement. Procedia Soc Behav Sci. 2015;177:65–70.

    Article  Google Scholar 

  94. Faber J, Fonseca LM. How sample size influences research outcomes. Dental Press J Orthodontics. 2014;19:27–9.

    Article  Google Scholar 

  95. Andrade C. Sample size and its importance in research. Indian J Psychol Med. 2020;42(1):102–3.

    PubMed  PubMed Central  Article  Google Scholar 

  96. Ceka A, Murati R. The role of parents in the education of children. J Educ Pract. 2016;7(5):61–4.

    Google Scholar 

  97. Zimmerman B. Social learning, cognition, and personality development. Int Encyclopedia Soc Behav Sci. 2001:14341–5.

  98. Birch LL. The relationship between children’s food preferences and those of their parents. J Nutr Educ. 1980;12(1):14–8.

    Article  Google Scholar 

  99. Scaglioni S, De Cosmi V, Ciappolino V, Parazzini F, Brambilla P, Agostoni C. Factors influencing children’s eating behaviours. Nutrients. 2018;10(6):706.

    PubMed Central  Article  Google Scholar 

  100. Sandstrom H, Giesen L, Chaudry A. How contextual constraints affect low-income working parents' child care choices. Washington, DC: Urban Institute; 2012.

    Book  Google Scholar 

  101. Pilarz AR. Mothers’ work schedule inflexibility and Children’s behavior problems. J Fam Issues. 2021;42(6):1258–84.

    PubMed  Article  Google Scholar 

  102. Centres for Disease Control and Prevention. Strategies for involving parents in school health. Atlanta, GA: U. S Department of Health and Human Services; 2012.

    Google Scholar 

  103. Zhao J-G. Combination of multiple databases is necessary for a valid systematic review. Int Orthop. 2014;38(12):2639–9.

    PubMed  Article  Google Scholar 

  104. Haidich A-B. Meta-analysis in medical research. Hippokratia. 2010;14(Suppl 1):29.

    CAS  PubMed  PubMed Central  Google Scholar 

  105. Ohly H, Gentry S, Wigglesworth R, Bethel A, Lovell R, Garside R. A systematic review of the health and well-being impacts of school gardening: synthesis of quantitative and qualitative evidence. BMC Public Health. 2016;16(1):1–36.

    Google Scholar 

  106. Rockoff JE. The impact of individual teachers on student achievement: evidence from panel data. Am Econ Rev. 2004;94(2):247–52.

    Article  Google Scholar 

  107. Hart K, Bishop J, Truby H. An investigation into school children's knowledge and awareness of food and nutrition. J Hum Nutr Diet. 2002;15(2):129–40.

    CAS  PubMed  Article  Google Scholar 

  108. Scaglioni S, Salvioni M, Galimberti C. Influence of parental attitudes in the development of children eating behaviour. Br J Nutr. 2008;99(S1):S22–5.

    CAS  PubMed  Article  Google Scholar 

Download references

Acknowledgements

The authors would like to acknowledge funding support from the UK Biotechnology and Biological Sciences Research Council (BBSRC).

Funding

This research was funded by UK Biotechnology and Biological Sciences Research Council (BBSRC) (Grant number: BB/T008989/1), with a project title of “Addressing micronutrient deficiencies associated with the double burden of childhood malnutrition in China, a combined food system framework”.

Author information

Authors and Affiliations

Authors

Contributions

CLC and PYT conducted searches, screening, quality assessment and data extraction; CLC wrote the first draft of the manuscript; PYT and YYG edited and revised the manuscript; all the authors read and approved the final manuscript.

Corresponding author

Correspondence to Yun Yun Gong.

Ethics declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary Information

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Chan, C.L., Tan, P.Y. & Gong, Y.Y. Evaluating the impacts of school garden-based programmes on diet and nutrition-related knowledge, attitudes and practices among the school children: a systematic review. BMC Public Health 22, 1251 (2022). https://doi.org/10.1186/s12889-022-13587-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s12889-022-13587-x

Keywords

  • School-aged children
  • School garden-based programmes
  • Nutritional knowledge
  • Attitudes
  • Food acceptability
  • Dietary practices
  • Fruits and vegetables