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1 This article was downloaded by: [Tel Aviv University] On: 17 February 2015, At: 05:16 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: Registered office: Mortimer House, Mortimer Street, London W1T 3JH, UK Critical Reviews in Food Science and Nutrition Publication details, including instructions for authors and subscription information: Systematic Review Demonstrating that Breakfast Consumption Influences Body Weight Outcomes in Children and Adolescents in Europe Hania Szajewska a & Marek Ruszczyński a a The Medical University of Warsaw, Department of Pediatrics, Warsaw, Poland Published online: 28 Jan To cite this article: Hania Szajewska & Marek Ruszczyński (2010) Systematic Review Demonstrating that Breakfast Consumption Influences Body Weight Outcomes in Children and Adolescents in Europe, Critical Reviews in Food Science and Nutrition, 50:2, , DOI: / To link to this article: PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the Content ) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at

2 Critical Reviews in Food Science and Nutrition, 50: (2010) Copyright C Taylor and Francis Group, LLC ISSN: DOI: / Systematic Review Demonstrating that Breakfast Consumption Influences Body Weight Outcomes in Children and Adolescents in Europe HANIA SZAJEWSKA and MAREK RUSZCZYŃSKI The Medical University of Warsaw, Department of Pediatrics, Warsaw, Poland Skipping breakfast is common among children and adolescents. However, there is uncertainty regarding whether breakfast consumption contributes to or protects against overweight or obesity. We aimed to review the evidence on the effects of breakfast consumption on body weight outcomes in children and adolescents in Europe. The Cochrane Library, MEDLINE, and EMBASE were searched in January We identified 16 studies. All were cross-sectional or cohort trials involving more than 59,000 children/adolescents from Europe. Thirteen studies (n = 57,481) consistently showed that breakfast has a protective effect against becoming overweight or obese. One trial (n = 886) showed that this effect was significant only for boys. The effect of eating breakfast on the body mass index (BMI) was analyzed in 4 studies (n = 2897). All of these studies showed an increase in BMI in breakfast skippers. In one study (n = 1245), this effect was significant only for boys. The results of this analysis suggest that eating breakfast is associated with a reduced risk of becoming overweight or obese and a reduction in the BMI in children and adolescents in Europe. However, almost all of the data in this review were gathered from observational studies, thus, causality should not be assumed based on these findings. Keywords INTRODUCTION Breakfast, breakfast skipping, overweight, obesity, nutrition Worldwide obesity is now reaching epidemic proportions, stimulating research to identify factors that affect energy balance. While it is clear that genetic factors are important in determining body weight, others such as behavioral and environmental factors also contribute. Breakfast is commonly considered a key component of a healthy diet. However, skipping breakfast is common. It is estimated in the United States for example that approximately 8% of children and 20% 30% of adolescents skip breakfast. The risk of skipping breakfast is higher in female students, children from lower socioeconomic backgrounds, and older children and adolescents (Siega-Riz et al., 1998). Recognized barriers to eating breakfast include a lack of time, not feeling hungry in the morning, and weight concerns (Reddan et al., 2002). Given the scale of breakfast skipping among children and adolescents on Address correspondence to: Hania Szajewska (MD), Department of Pediatrics, The Medical University of Warsaw, Warsaw, Dzialdowska 1, Poland. hania@ipgate.pl one hand and the worldwide epidemic of overweight and obesity on the other, there is a question as to whether there are risks associated with omitting the first meal of the day. Previously, one systematic review aimed at determining the health effects of breakfast skipping in children and adolescents was performed (Rampersaud et al., 2005). This review, published in 2005 (search date: from 1970 through February 2004), identified 16 trials that examined the association between breakfast consumption and body weight. The authors found that although breakfast eaters consumed more daily calories, they were less likely to be overweight. However, it was noted that not all studies associated breakfast skipping with being overweight. A number of studies have since been published. Yet, there is still uncertainty regarding the effect of breakfast consumption on body weight. Therefore, our aim was to systematically review and update data from studies on the effect of breakfast consumption on body weight in children and adolescents in Europe. The rationale for this was that there are large variations in breakfast composition worldwide. While these variations are present in Europe also, one may assume that they are less pronounced than those found worldwide. 113

3 114 H. SZAJEWSKA AND M. RUSZCZYŃSKI METHODS The Cochrane Central Register of Controlled Trials (CEN- TRAL, the Cochrane Library, Issue 4, 2008), MEDLINE ( ), and EMBASE ( ) databases were systematically searched in January The reference lists of identified studies and key review articles, including previously published reviews, were also searched for all randomized and non-randomized clinical trials as well as prospective cohort and cross-sectional studies that assessed the effect of breakfast consumption, however defined, on body weight in children and adolescents. No language restrictions were imposed. Only studies conducted in Europe were included. The primary outcome measures were as follows: body weight, or a change in body weight (e.g., overweight, obesity), and body mass index (BMI). Included studies had to report at least one of these primary outcomes. In addition to these outcomes, a priori we decided to extract other data reported by the investigators if clinically relevant to the current review. The following search terms were used: breakfast and relevant population terms [e.g., child* or adolescent* to select a study population of less than 18 y of age] with appropriate truncations and misspellings. The search strategy used both keywords and MeSH terms. No further limitations were made so the search terms would be as sensitive as possible. One reviewer searched the databases. We excluded studies if the title and abstract were not relevant. However, we obtained papers for all potentially relevant studies if the abstract contained insufficient information to warrant exclusion. Data from each study were extracted using a standardized data-extraction form. Statistical Methods The data were analyzed using Review Manager (RevMan) [Computer program. Version 5.0. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2007]. The weighted mean difference (WMD), as appropriate, between the treatment (breakfast skippers) and control (breakfast eaters) groups was selected to represent the difference in continuous outcomes (with 95% CI). When a meta-analysis was not possible because of heterogeneity, the results are presented in narrative form. et al., 2002; Cartwright et al., 2003; Keski-Rahkonen et al., 2003; Sjoberg et al., 2003) All studies were cross-sectional or cohort studies. Participants were children and adolescents from European countries such as Croatia, Czech Republic, Denmark, Finland, Greece, The Netherlands, Norway, Portugal, Spain, Sweden, and the United Kingdom; they were aged 7 21 y and were from different socioeconomic backgrounds. Excluded trials, including the reasons for exclusion, are available upon request. A definition of breakfast was provided in only 3 studies (Vanelli et al., 2005; Keski-Rahkonen et al., 2002; Sjoberg et al., 2003). Although almost all of the studies provided criteria for breakfast skipping, there were variations in those criteria (Table 1). In some studies, the authors used, breakfast frequency (number of days with eaten breakfast) to define breakfast skipping. In other studies, breakfast skipping was defined according to the number of breakfasts eaten or skipped weekly. The definition of overweight/obesity also varied across the studies (Table 1). Breakfast Skipping and BMI The effect of breakfast consumption on BMI was analyzed in 4 trials (Dialektakou et al., 2008; Bralić et al., 2005; Gikas et al., 2003; Sjoberg et al., 2003). A meta-analysis of 3 trials (Bralić et al., 2005; Gikas et al., 2003; Sjoberg et al., 2003) (2086 participants) showed an increase in BMI of 0.78 kg/m2 (95% CI 0.51 to 1.04) in breakfast skippers compared with breakfast eaters (Fig. 1). Changing our meta-analysis model from fixed to random effects did not change the results. Additionally, Dialektakou and Vranas (2008) found a significant association (P < 0.05) between breakfast skipping and BMI in 29 of the 48 linear regression models that were used in their study. Breakfast Skipping and Overweight/Obesity Thirteen trials (n = 57,481) assessed the association between breakfast skipping and overweight/obesity and consistently showed that eating breakfast has a protective effect against becoming overweight or obese. In brief, Fabritius and Rasmussen found in a study involving 4824 participants that students who ate breakfast 0 1 weekdays per week compared to frequent RESULTS Search Results and Description of Studies Table 1 summarizes the key characteristics of the 16 included studies involving 59,528 participants (Fabritius et al., 2008; Henríquez Sánchez et al., 2008; Dialektakou et al., 2008; Mota et al., 2008; Harding et al., 2008; Vågstrand et al., 2007; Croezen et al., 2009; Vanelli et al., 2005; Bralic et al., 2005; Andersen et al., 2005; Gikas et al., 2003; Ortega et al., 1998; Kovarova Figure 1 Meta-analysis of the association between breakfast skipping and body mass index.

4 Table 1 Characteristics of included trials Definition of Definition of Study ID Study design Study aim Participants breakfast skipping overweight/obesity Confounding Factors Results Fabritius and Rasmussen 2008 Henriquez Sanchez P et al., 2008 Dialektakou and Vranas 2008 Cross-sectional school survey To assess whether skipping breakfast in lower socioeconomic status position (SEP) patients is connected with overweight Cross-sectional To estimate the prevalence of obesity/overweight among Canary adolescents and its association with breakfast intake Cross-sectional To assess whether an association between skipping breakfast and overweight depends on the definition of breakfast skipping Mota et al., 2008 Cross-sectional To assess the associations and impact of increased meal frequency, physical activity, and skipping breakfast on obesity levels Harding et al., 2008 Vagstrand et al., 2007 Cross-sectional To assess ethnic and lifestyle influences on obesity Cross-sectional To investigate if eating habits among adolescents are related to body fatness and gender Croezen 2007 Cross-sectional To assess the association between breakfast skipping and risky behaviors and overweight/obesity Vanelli et al., 2005 Bralic and Kovacic 2005 Cross-sectional To assess breakfast habits and their relationship to nutritional status Cross-sectional To assess the correlation between social, behavioral, and nutritional habits and BMI N = 4824, y (Denmark) N = 1001, y, (Spain) N = 811, High school students Aged y (mean:16.62 y) (Greece) N = y, urban, (Portugal) N = 6599, y, (UK) N = y (Sweden) N = 25, y (grade 2) y (grade 4) (The Netherlands) N = y and y (Italy) N = ±1.19 y (females) (Croatia) Frequency of breakfast/week: skipper 0 1/week Breakfast eaten: yes or no 24 different definitions of breakfast skipping Self-reported breakfast skipping no further details Defined with BMI cut-off points according to Cole BMI percentile chart >85% overweight >97% obesity Age- and sex-specific BMI cut-off points proposed by IOTF criteria According to age-and sex-specific BMI cut-points (25 30 at 18 years, according to Cole) Not defined IOTF age-specific thresholds Frequency of breakfast per week: never 1 4 times per week, 5 6 times/week, or daily; type of breakfast Frequency of breakfast per week (0,1 2, 3 4,5 6,7) Self-reported breakfast skipping during 15 days Skip breakfast less than 3 times a week Skipping breakfast self-reported as routinely or occasionally Body fatness (BF%) was measured using the BodPod system (measuring volume and mass of the object and calculating its density) BMI cut -off points for overweight and obesity by Cole BMI cut-off points for overweight and obesity by Cole Socioeconomic factors, parental occupational class Physical activity (hours devoted to television and video games vs. sport) sex, ethnicity, smoking, dieting, parental education Skipping breakfast was associated with overweight. Students who only ate breakfast 0 1 weekdays per week: OR for overweight: 1.80 (95% CI: ). Frequent consumption of breakfast: less protective against overweight among low SEP schoolchildren An inverse relationship between breakfast and its quality and obesity was observed. Girls: (% of overweight in group of eaters vs. skippers) 11.5% vs. 17.5% (% of obese in group of eaters vs. skippers) 16.5% vs. 30%, p = Boys: (% of overweight in group of eaters vs. skippers) 10.5% vs. 18.2% (% of obese in group of eaters vs. skippers) 11.3% vs. 27.3%, p = Fewer breakfast-skipping variables were associated with BMI than with overweight/obesity. Fewer associations were found when controlling than when not controlling for potential confounders. Fewer associations were found for variables corresponding to some definitions of breakfast skipping than for variables corresponding to other definitions. Meal frequency, physical activity Obese girls and skipping breakfast -NS Obese boys skipped breakfast significantly more (13% vs. 5.6%; p 0.05) than ethnicity, parental and adolescent health- related influences (smoking, dietary habits, sex) Sex, energy intake, nutritional habits Amount of alcoholic drinks consumed per occasion, number of physically active days per week their normal-weight counterparts did. Association between skipping breakfast and obesity: girls OR 1.74, 95% CI ; boys OR 2.06; CI Regularity of breakfast eating was not significantly associated with body fatness % Unadjusted OR for relationship between breakfast skipping and overweight/ obesity (OR 1.68; 95% CI for grade 2, OR % CI for grade 4). Snacking and dietary habits 78% usually had breakfast; 22% reported skipping breakfast. Skippers vs. non-skippers: overweight: 27.5% vs. 9.1%, p = 0.01 obesity: 9.6% vs. 4.5%, p = Dieting, smoking, first menarche date, school performance, lunch consumption, milk consumption, sport activities BMI of breakfast skippers versus non skippers: 21.0±2.37 vs ±1.9 P < (Continued on next page) 115

5 Table 1 Characteristics of included trials (Continued) Definition of Definition of Study ID Study design Study aim Participants breakfast skipping overweight/obesity Confounding Factors Results Andersen et al., cross-sectional surveys in 1993 and in 2000 To assess the prevalence of overweight/obesity and associated factors Gikas et al., 2003 Cross-sectional To assess the prevalence of breakfast eating and its correlation to nutritional status and socioeconomic factors To assess whether breakfast skipping was associated with other unhealthy food habits Ortega et al., 1998 Kovarova et al., 2002 Cartwright et al., 2003 Keski-Rahkonen et al., 2003 Sjoberg et al., 2003 Self-reported 7 consecutive day food record Comparison of breakfast habits of obese/overweight and normal- weight schoolchildren Cross-sectional To assess the prevalence of obesity in prepubertal children Cross-sectional To test the hypothesis that higher levels of life stress are associated with higher levels of unhealthy dietary practices Cross-sectional Five birth cohorts of adolescent twins and their parents To investigate which sociodemographic factors and behaviors are associated with breakfast skipping in adolescents and adults. Cross-sectional To relate meal patterns of Swedish adolescents to food choice, nutrient intake, and other lifestyle factors. N = 3139 Primary school students, 4th and 8th graders Data from two cross sectional surveys (Norway) N = y, (Greece) N = y (Spain) N = y (Czech Republic) N = y (UK) N = 5448 twins 16 y (Finland) N = y (Sweden) Frequency of eating breakfast per week International cut-off points for BMI for overweight and obesity, based on centile curves defined to pass through the BMI of 25 and 30 kg/m 2 at the age of 18 y Skippers not defined Adolescents with BMI 85th percentile for age, sex and white race were classified as overweight/obese, while those with BMI < 85th percentile were classified as normal Breakfast consumption during 7 consecutive days Breakfast consumption habitual breakfast consumption Breakfast frequency according to a 5-point Likert scale (from 1 = least frequent breakfast consumption to 5 = most frequent breakfast consumption) Frequency of breakfast: every morning, a few times a week, about once a week or less often. Skipper: eating breakfast 1/week Irregular breakfast intake: skipping breakfast at least 1/week Overweight/obesity: - BMI >75th percentile Underweight: BMI <10th percentile; overweight: BMI 90th-97th percentile; obesity: BMI >97th percentile Overweight/obesity defined in accordance with standardized predicted growth curves developed by Cole IOTF criteria with age-and sex-specific cut-off points defined to pass through BMI of 25 kg/m 2 at age 18 y Lifestyle habits such as watching tv, energy consumption, sweets consumption; age, physical activity Sex, geographic area, maternal/paternal education, paternal occupation, working mother, dietary habits, alcohol consumption Adj OR for overweight in children who ate breakfast: 3 5/week: (OR 1.99; 95% CI ) <= 2 /week (OR 1.69; 95% CI ) Mean BMI was higher in breakfast skippers than eaters (22.6 ± 3 vs ± 2.8, P = 0.008). adj OR for obesity 1.9, 95% CI , p = Sex Overweight/obese children, especially female subjects, omitted breakfast more frequently compared to normal-weight subjects (P <0.05) Maternal education, sex, age, anthropometric measurements, dietary habits, physical activity Demographic factors, stress, dietary habits, snacking, Thrill and adventure seeking, self-perceived health, dietary spread used for bread, parental unemployment, parental breakfast eating, smoking, exercise, education level at 17 y, sex, alcohol use, behavioral disinhibition, alcohol use, age of puberty onset Lunch consumption, regularity of meals, smoking, ethnicity, low socioeconomic index, considered weight too high In the group of obese children, 54.1% had breakfast compared to 75.3% in the group of underweight children (P <0.001) Overweight children were less likely to eat breakfast every day (OR 0.72; 95% CI ; p < 0.01) Breakfast skippers compared to breakfast eaters had a doubled chance of having a BMI (adj. for sex) >25 kg/m 2 (OR 2.0; 95% CI ; p 0.001) For boys, BMI was higher (21.4 ±3.3 vs. 20.5±2.5 kg/m 2 [P = 0.006]) for subjects with irregular breakfast intake compared with subjects with regular breakfast intake, but this difference did not exist for the girls (21.2±2.4 vs. 20.9± 2.9 kg/m 2 ). BMI, body mass index; CI, confidence interval; IOTF, International Obesity Task Force; OR, odds ratio; y, years. 116

6 EFFECT OF BREAKFAST CONSUMPTION ON BODY WEIGHT 117 breakfast eaters who ate breakfast more than 3 weekdays per week were almost twice as likely to be overweight (OR 1.8; 95% CI 1.38 to 2.36) (Fabritius et al., 2008). The effect was less meaningful among children from families of low socioeconomic status. In a study involving 1001 participants, Sánchez Henríquez et al., found a higher prevalence of overweight/obese children in the group that skipped breakfast compared to the group of breakfast consumers both for girls (overweight: 17.5% vs. 11.5%; obesity: 30% vs. 16.5%) and for boys (overweight: 18.2% vs. 10.5%; obesity: 27.3% vs. 11.3%) (Sanches-Henriquez et al., 2008). Dialektakou and Vranas assessed the association between different breakfast skipping definitions and overweight/obesity defined according to International Obesity Task Force (IOTF) criteria in a study involving 811 participants (Dialektakou et al., 2008). For example, for children who ate an average of 0 1 breakfasts/week, the odds ratio for overweight/obesity was 1.97 (95% CI ; p = 0.002). Mota et al. observed in a study involving 886 participants that obese boys were significantly more likely to skip breakfast compared with their normal-weight counterparts (13% vs. 5.6%; p < 0.05) (Mota et al., 2008). No such difference was observed in girls. In a large trial by Harding et al., involving 6599 participants of different ethnicities from the UK, breakfast skipping almost doubled the odds ratio for obesity both for girls (OR 1.74; 95% CI 1.30 to 2.34) and for boys (OR 2.06; 95% CI 1.57 to 2.70) (Harding et al., 2008). A study by Croezen et al. (2009) involving 25,176 Dutch teenagers demonstrated a strong association between skipping breakfast and overweight in second and fourth grade children (OR 1.68; 95% CI for grade 2; OR 1.32; 95% CI for grade 4) as well as obesity (Croezen et al., 2009). Vanelli et al. found in a study involving 1202 participants that overweight and obesity were more frequent in the group of breakfast skippers compared with the group of breakfast consumers (27.5% vs. 9.1%, p = 0.01 and 9.6% vs. 4.5%, p = 0.04, respectively) (Vanelli et al., 2005). Andersen et al. performed 2 cross-sectional surveys of Norwegian schoolchildren (n = 3139) in 1993 and They reported that the consumption of breakfast 3 5 times per week was associated with an increased chance of being overweight (adj. OR 1.99; 95% CI ). Interestingly, this association lost its significance in children who ate breakfast 2 or fewer times per week (adj. OR 1.69; 95% CI ) (Andersen et al., 2005). Gikas et al. showed in a study involving 513 participants that breakfast skipping was independently related to overweight/obesity (adjusted OR 1.9; 95% CI 1.12 to 2.88; p = 0.015) (Gikas et al., 2003). In a study by Ortega et al., involving 200 participants, the authors showed that overweight/obese subjects, particularly females, were more prone to skipping breakfast compared to normal-weight subjects (Ortega et al., 1998). The authors also reported that 2.3% of the nonobese boys skipped breakfast compared to 3.3% of the overweight/obese boys. In the girls population, 1.7% of the nonobese girls skipped breakfast compared to 8.7% of the overweight/obese girls (p < 0.05). Moreover, in a study by Kovarova et al., involving 3362 participants, the authors reported that fewer overweight children consumed breakfast compared to their underweight counterparts (54.1% vs. 75.3%; p < 0.01) (Kovarova et al., 2002). Similarly, in a study involving 4320 participants, Cartwright et al., found that overweight adolescents were less likely to consume breakfast every day compared with normal-weight subjects (OR 0.72; 95% CI 0.64 to 0.81; p < 0.01) (Cartwright et al., 2003). Finally, in a study by Keski-Rahkonen et al., involving 5448 participants, the authors reported that breakfast skippers compared to breakfast eaters were two times more likely to have a BMI >25 kg/m 2 (adjusted for sex OR 2.0; 95% CI 1.32 to 3.01; p 0.01) (Keski-Rahkonen et al., 2003). Other Outcomes One small study (n = 474) showed a lack of an association between breakfast frequency and body fat% measured with the use of the BodPod Body Composition System (Vågstrand et al., 2007). DISCUSSION Principal Findings Collectively, the data from observational studies carried out in Europe have consistently shown that children and adolescents who eat breakfast have a reduced risk of becoming overweight or obese and have a lower BMI compared with those who skip breakfast. These results are in line with previous results from cross-sectional studies and several small prospective cohort studies carried out outside of Europe (Duncan et al., 2008; Dubois et al., 2006; Utter et al., 2007; Timlin et al., 2008). Study Limitations This systematic review has several limitations. Although the search strategy was thorough, some studies might have not been located, particularly if published in local languages. We included only published reports. No effort was made to locate any unpublished studies which, based on our previous experience, is rarely successful. Consequently, a publication bias cannot be excluded. Almost all of the data in this review were gathered from observational studies, thus, causality should not be assumed based on these findings. The inclusion of randomized controlled trials would increase the validity of the results of a systematic review by reducing bias and random error and by

7 118 H. SZAJEWSKA AND M. RUSZCZYŃSKI providing only the highest level of evidence. Unfortunately, no such studies have been identified. The question remains open as to whether a randomized controlled trial that involves breakfast skipping in children for a certain period of time can be expected. An additional potential limitation of this systematic review stems from the various definitions of breakfast skipping. The importance of the definition of breakfast skipping has recently been revived by the publication by Dialektakou and Vranas (2008). This paper clearly shows that whether an association between breakfast skipping and BMI or breakfast skipping and overweight/obesity exists depends on how breakfast skipping is defined. The criteria for breakfast skipping used in the trials included in this review differed from study to study and sometimes could not be directly compared. Given all of the considerations discussed above, the evidence presented in this systematic review may be encouraging but not fully convincing. Potential Confounders Confounding factors are considered to be the most important threat to the validity of results from observational studies (Egger et al., 2003). Any study assessing the impact of breakfast consumption on the risk of overweight and obesity should attempt statistical adjustments for confounding factors. Commonly considered confounders in these studies of the relationship between obesity or overweight and breakfast eating were birth weight, parental obesity, dietary factors, physical activity, socioeconomic status, age, and sex. The included studies varied in the degree of controlling for potential confounders. This is important, as it has been documented that analyses that adjust for confounding variables often do not reach statistical significance. For example, in a recent 5-year prospective study, investigators in the USA examined the association between breakfast eating patterns and self-reported BMI and weight changes in 2216 adolescents at the mean ages of 15 y and 19 y. They found that breakfast skipping was associated with weight gain, although this association did not reach statistical significance after adjustments for dietary, psychosocial, and other confounding variables, suggesting some uncertainty about the strength of this association (Timlin et al., 2008). Possible Mechanisms The mechanism by which breakfast consumption may exert its action in preventing obesity is unclear. Some potential mechanisms have been extensively discussed in a number of previous studies and review articles, 1 including the fact that daily breakfast eaters seem to be more physically active compared with 1 Presented as part of the invited workshop Overall dietary balance for good nutrition in children: the relevance of breakfast given at the 2008 MilanoPediatria meeting, November 22, 2008, in Milan, Italy. The workshop was sponsored by Soremartec Italia SrL. Its contents are solely the responsibility of the authors. The Symposium was chaired by Marcello Giovannini and Raanan Shamir. breakfast skippers. Also, those who regularly consume breakfast have dietary profiles that potentially could improve energy balance and weight control, such as the consumption of fiber-rich products (i.e., breakfast cereals and breads) that may improve glucose and insulin parameters, increase satiety, and lower body weight (Giovannini et al., 2008). Another possible mechanism that may contribute to the higher risk of obesity/overweight in breakfast skippers is that one of the most widely eaten breakfasts is ready-to-eat cereal; existing data suggest that eating this type of meal is inversely related to body weight (Barton et al., 2005). CONCLUSIONS AND FUTURE RESEARCH In summary, this systematic review of observational studies indicates that breakfast consumption is associated with a reduced risk of overweight or obesity and a reduction in the BMI in children and adolescents in Europe. However, all of the data in this review were gathered from observational studies, thus, causality should not be assumed based on these findings. 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