Introduction
Down’s syndrome (DS) is a chromosomal mutation involving a tripling of the genetic material on the 21st chromosome. It is the most common genetic disorder. Between 2011 and 2015 in Europe, 8031 live births of children with DS were recorded each year. The prevalence of DS was 10.1 per 10,000 live births [1]. Individuals with DS display abnormalities in relation to their brain structure, function and development that lead to varying levels of intellectual disability [2–4]. Furthermore, individuals with DS are more likely than the general population to display congenital heart disorders, defects of the gastrointestinal tract, defects of the urogenital, muscular, osteoarticular and haematopoietic systems, impaired immune response, vision and hearing, epilepsy, type 1 diabetes, leukaemia and Alzheimer’s disease [3, 5, 6], thyroid hormone disorders [7, 8], diseases of the oral cavity and teeth [9], food intolerances, malabsorption syndrome, metabolic disorders, and vitamin and mineral deficiencies [10, 11].
Many studies have indicated a higher prevalence of overweight and obesity in children with DS, compared to their peers without DS [7, 10–13]. Basil et al. observed a 47.8% prevalence of obesity in children with DS aged 2–18 years, compared to 12.1% in a control group of children [12]. A review of the literature conducted by Bertapelli et al. demonstrated that the prevalence of being overweight and obese in children and youth with DS aged 0–19 years ranged from 23% to 70% [7]. The causes of overweight and obesity in children with DS include metabolic disorders, compulsive eating caused by difficulties in chewing food, muscle hypotonia leading to decreased satiety after meals and abnormal blood leptin levels, as well as comorbidities such as hypothyroidism [7, 12, 14–16]. However, the studies do not provide clear results with respect to the genetic causes of obesity in children with intellectual disabilities. Researchers have also indicated the role of environmental factors, including bad dietary habits and insufficient physical activity in children with DS [7, 11].
Overweight in children with DS is associated with many disorders. It is thought to increase the risk of dyslipidaemia, hyperinsulinemia, stroke, heart failure, hypertension, type 2 diabetes, obstructive sleep apnoea and incorrect gait. However, the relationship between obesity and health is difficult to determine due to the high number of comorbidities associated with DS [7, 11, 17]. Obesity not only leads to severe health problems, but also impacts an individual’s ability to self-manage [18], which is crucial in the case of individuals with special needs, including patients with DS.
Aim of the research
The aim of this study was to assess the dietary habits and physical activity, and their associations with nutritional status, in children with DS compared to a group of their typically developing peers.
Material and methods
Research organisation
The study participants comprised children with DS aged 5–14 years. The control group consisted of their peers without DS or other genetic disorders. The participants were selected using snowball sampling from among the members of associations and foundations for children with DS and their parents, as well as from preschools and primary schools attended by children both with and without DS. The participants lived in large cities and in their vicinity, in the areas of central-eastern and southern Poland (Kielce, Krakow, Lublin, Warsaw) with the aforementioned foundations. From a total of 108 children with DS and 115 children without DS recruited for the study, 6 of the children with DS and 8 children without DS were rejected due to incomplete or illegible data. The final sample size for the nutritional assessment was 102 children with DS and 107 children without DS. The assessment of the physical activity using pedometers was performed among 101 of the children with DS and 107 children without DS.
The study received Approval No. 47/2018 from the Bioethics Committee at the Collegium Medicum of the Jan Kochanowski University of Kielce. Prior to the study, the parents or guardians of each child provided written consent for their participation.
Research methods and tools
Methodology for the nutritional status assessment and results analysis
The participants’ nutritional status was assessed based on the body mass (kg) and height (cm), which were used to calculate the BMI (kg/m2). Body fat percentage (%BF) was determined based on bioelectric impedance using an Inbody 120 body composition analyser. The interpretation of the data concerning the nutritional status of the children with and without DS was based on the Polish developmental standards for children and youth [19]. Both of the groups were divided into children with a low (< 10 centile), normal (10–90 centile) and high (> 90 centile) BMI. The participants’ %BF was compared to the Polish weight and height standards for children and youth [20]. Consequently, both groups were divided into children with a low (< 10 centile), normal (10–90 centile) and high (> 90 centile) %BF.
Methodology for the analysis of dietary habits
The participants’ dietary habits were assessed using the patient’s diary method over a period of 3 days. The diaries were filled in by the children’s parents or guardians. The nutritional content of the children’s diets was then estimated using the Dieta 6 software. The intake of nutrients, including proteins, fats, carbohydrates, dietary fibre and sucrose, was calculated. The mean intake of these nutrients was presented, according to age and gender, based on the Polish dietary norms [21]. Furthermore, the adequacy of the intake of protein and dietary fibre was assessed using the Estimated Average Requirement/Adequate Intake (EAR/AI) cut-off point, in order to estimate the percentage of children with a usual intake that was lower than the EAR/AI. This yielded data concerning the magnitude of the populational risk of an insufficient intake of a nutrient in the sample. The cut-off point method was not used in the case of energy, because the intake of energy increases with the demand. Instead, the distribution of the BMI in the sample was determined and used to analyse the nutritional state.
Assessment methodology for physical activity and the results analysis
The participants’ level of physical activity was measured by counting the steps taken per day, over a period of three days, using Tanita AM-180E pedometers. Three categories of physical activity were distinguished as follows: sedentary lifestyle (< 7000 steps/day in girls and < 10000 steps/day in boys), low activity (7000–9499 steps/day in girls and 10,000–12,499 steps/day in boys), and moderate to high activity (≥ 9500 steps/day in girls and ≥ 12,500 steps/day in boys) [22].
Additional data concerning the participants’ age, number of family members and the family’s financial situation were collected using a survey questionnaire.
Statistical analysis
The statistical analysis was performed using the StatSoft Statistica PL v. 13.1 software package. The data were considered to be statistically significant at p ≤ 0.05. The distribution of categorical variables was assessed using Pearson’s c2 test. Quantitative and ordinal variables were compared between the groups using Student’s t-test or the Mann-Whitney U test, depending on whether the requirements related to the normality of distribution and the uniformity of variables were met. Pearson’s linear correlation coefficient was used to determine the relationship between a participant’s intake of energy, intake of nutrients and physical activity, and their nutritional status. The effect of each factor on the indicators of the nutritional status (BMI and %BF) was estimated by creating separate multifactor models for the children with and without DS. Independent variables included the child’s age, gender, family’s financial situation, number of underage family members, intake of energy, total intake of fat, total carbohydrates and sucrose, and physical activity based on the number of steps taken per day.
Results
Participant characteristics
The participants with DS and without DS (the control group) did not differ significantly in terms of age (Table 1). Boys made up a higher percentage of the DS group than the control group. The number of family members, as well as the number of underage family members, was significantly lower in the DS group than in the control group. No significant difference in the family’s financial situation between the groups was observed.
Assessment of nutritional status
The children with DS showed a significantly higher BMI than the control group (Table 2). The percentage of children classified as having overweight and obesity was also significantly higher in the participants with DS than in the control (56.9% and 15.0%, respectively). More children in the DS group also had a high %BF (> 90 centile) than in the non-DS group (86.3% and 52.3%, respectively).
Assessment of nutrient intake
The children with DS aged 4–6 years consumed significantly less sucrose and dietary fibre compared to the control group, while the children with DS aged 7–9 years consumed significantly less protein and sucrose compared to the control group (Table 3). Boys with DS aged 10–12 years consumed significantly less energy, protein, fat, sucrose and dietary fibre compared to their peers without DS. In the girls of the same age, a lower intake of sucrose in the girls with DS was the only significant difference observed between the two groups. The diet of the girls with DS aged 13–15 years contained less energy and total carbohydrates, sucrose and dietary fibre compared to the diet of the girls without DS. Conversely, the boys with DS of the same age consumed significantly less energy and protein compared to the control group.
The mean intake of protein was the same among the children with and without DS. In both groups, protein accounted for 16% of the overall energy. The populational risk of an insufficient intake of protein was higher in the children with DS than in the control group, being 15.7% in the former group and less than half this value in the latter (Table 4). However, the difference was not statistically significant. Fats accounted for 28% of the dietary energy in the children with DS and 30% in the controls, while carbohydrates accounted for 56% and 54%, respectively. Sucrose accounted for 9% and 12%, respectively, with the children without DS consuming significantly more sucrose than the recommended 10% of the daily energy intake. The children with DS also showed a significantly higher risk of an insufficient intake of dietary fibre compared to their peers in the control group.
Assessment of participants’ physical activity
The assessment of the participants’ physical activity showed that the children with DS took much fewer steps per day, on average, than the children without DS (3927.2 ±2348.1 vs. 6901.8 ±3314.1). A vast majority of the children with DS (almost 90% of the sample) had a sedentary lifestyle (Table 5), compared to 59.8% of the children without DS. One in 3 children without DS showed a low level of physical activity, while several showed moderate or high levels of physical activity.
Relationship between participants’ dietary habits and physical activity and their nutritional status
An increased intake of energy and total carbohydrates was related to an increase in the %BF among the children, both with and without DS, as well as being related to an increased BMI, but only in the control group (Table 6). In turn, a high intake of sucrose was positively associated with an increased BMI and %BF among both groups. No significant relationships were found between the total intake of fat or dietary fibre and the nutritional status indicators. Increased BMI and %BF were observed among both groups in the children who showed low levels of physical activity (took fewer steps per day than their peers). The strongest correlation occurred between the level of physical activity and the BMI in children without DS (r = –0.69).
A multivariate regression analysis was performed in order to determine what factors were associated with the participants’ nutritional status. A positive relationship was observed between the BMI in the children with DS and their age and intake of sucrose, while a negative relationship was observed between the BMI and physical activity, calculated as the number of steps taken per day (Table 7). With each year of age, the mean BMI increased by 0.23 kg/m2 (with the other parameters remaining constant). Each additional consumed gram of sucrose in the children with DS increased the BMI by 0.06 kg/m2. However, each additional step taken by the children with DS decreased the mean BMI by 0.0007 kg/m2. In the control group, the only observed relationships were a positive relationship between BMI and intake of sucrose, as well as a negative relationship between BMI and physical activity, as calculated based on the steps taken per day. The mean BMI increased by 0.05 kg/m2 with each additional consumed gram of sucrose, while it decreased by 0.0006 kg/m2 with each step taken. The constructed models explained the value of the BMI in the children with DS in 42% of the participants (R2 = 0.4190), and in the children without DS in 58% (R2 = 0.5829).
Furthermore, a negative relationship was observed between %BF in the children with DS and the number of underage family members, as well as physical activity calculated based on the number of steps taken, while there was a positive relationship between %BF and gender and the intake of carbohydrates (Table 8). The mean %BF (with the other parameters remaining constant) decreased by 1.24% with each additional underage family member and by 0.001% with each step that was taken. Moreover, the mean %BF was higher by 2.1% in the boys with DS than in the girls with DS. The intake of an additional gram of total carbohydrates increased the %BF by 0.04%. The control group showed a positive relationship between %BF and the intake of sucrose, as well as a negative relationship between %BF and physical activity. Specifically, the mean %BF increased by 0.05% with each additional consumed gram of sucrose and decreased by 0.001% with each step that was taken. The constructed models explained the %BF in 33% of cases (R2 = 0.3267) among the children with DS and in 35% (R2 = 0.3516) among the control group.
Discussion
An excessive body mass is not only the result of a positive energy balance, but is also a complex biochemical, physiological, sociological and psychological problem. However, the most important behavioural factors leading to the development of overweight and obesity are an incorrect diet and a low level of physical activity [23]. A correct diet and sufficient physical activity also play a major role in the lives of individuals with DS, and may benefit their health and development [7, 11, 24]. The results obtained in this study showed that children with DS had a significantly higher BMI and %BF compared to their peers from the control group. These results are consistent with those obtained by Basil et al., who observed that almost half (47.8%) of a sample of children aged 2–18 years had obesity, compared to 12.1% in a control group [12]. Other authors have also confirmed that children and youth with DS display an overweight and obese condition [7, 10, 25] and an increased %BF more often than their peers without DS [26].
The diets of the children, both with and without DS, contained a correct mean share of protein, fats and carbohydrates in relation to the daily energy demand. However, one in five children exceeded the daily recommended share of fats in their diet (> 35% of the energy demand) among both groups. The populational risk of an insufficient intake of protein was almost 16% in the children with DS, which was twice as high as in the control group. Less than 10% of the children with DS and less than 6% of the children without DS exceeded the recommended percentage of carbohydrates in their diet; but on the other hand, many of the children consumed an excessive share of sucrose. However, the children with DS adhered to the recommended intake of simple sugars, i.e. below 10% of the energy demand, significantly more often than their peers without DS [27]. The analysis of the results also indicated that the children with DS had a significantly higher risk of an insufficient intake of dietary fibre. Other authors who have conducted studies on individuals with DS also observed an incorrect intake of macronutrients. For example, children from Saudi Arabia with DS aged 6–18 years were found to consume much more carbohydrates and fats than a control group (children without DS) [11]. In turn, Roccatello et al. conducted a study among the Italian population, where they found that children with DS consumed too much protein and too little dietary fibre [28]. An insufficient intake of dietary fibre was also observed in the current study. Such an incorrect intake of nutrients in children with DS may be related to a frequent use of elimination diets [29] and to the consumption of highly processed foods with a low content of dietary fibre.
Most of the participants, in both groups, showed insufficient levels of physical activity. Even so, the children with DS had a significantly lower level of physical activity than the control. Other authors have also reported that the level of physical activity in children with DS was lower than in children without DS, with the daily duration of physical activity not exceeding 60 min in a vast majority of the former group [30]. Izquierdo-Gomez et al. conducted a study among youth aged 11–20 years, where they found that only 43% of teenagers with DS adhered to the recommended 60-min daily duration of physical activity [31]. However, the latest research has underlined a need to develop special criteria for the assessment of physical activity in individuals with DS, rather than measuring their physical activity using the same methods and intensity cut-off points that have been developed for their peers without DS [32]. The somatic traits characteristic for DS, including particular body proportions, muscle hypotony, joint hypermobility and bad posture, along with intellectual disability, can impede the motor functioning. Furthermore, the abnormal structure and function of the cardiovascular system reduces the ability of these individuals to perform sustained physical effort [33, 34]. To date, no specific criteria have been developed for children and youth with DS. On the other hand, the results of a different study showed that the cut-off points for sitting time that were designed for children with normal development can also be used for children with DS, because the children with disabilities did not show significantly different behaviours than the children without chronic diseases [35].
Nordstrøm et al. reported that overweight and obesity in children with DS appears as soon as the age of 4–5 years and added that this necessitates earlier prophylaxis, in order to prevent the development of chronic diseases at an older age [36]. In particular, obesity increases the risk of type 2 diabetes, insulin resistance, dyslipidaemia and hypertension. It may also make it difficult to provide care to the individuals with DS and can lead to a lower quality of life. Consequently, prophylactic measures to address obesity among children with DS are crucial. They should include introducing a healthy diet and increasing the amount of physical activity [37]. The results obtained in the current study indicated a relationship between an increased intake of energy, total carbohydrates and sucrose, and the nutritional state in children both with and without DS. Another study conducted among preschool children with DS showed that their nutritional state was affected by bad dietary habits, specifically, eating too much food. The children with DS who had overweight or obesity ate more meals at preschool – specifically, they ate two dinners (one at preschool and one at home) – considerably more often than their peers (80% vs. 55.6% of the sample). The same study also showed that as many as 25% of children with overweight or obesity children snacked every day [29]. An analysis of the studies conducted among children without DS shows that the children with overweight or obesity consumed an excessive amount of energy and showed an incorrect composition of their meals; in particular, there was an excessive share of simple sugars and saturated fats. A low content of fruits, vegetables and wholegrain products in the diet also caused an insufficient intake of dietary fibre [38–41].
The nutritional state of the children in the current study was also affected by their physical activity. Higher values of the nutritional state indicators were observed in the participants, both with and without DS, who were less physically active than their peers. These results are consistent with those obtained by Bertapelli et al., who found that physical activity may significantly reduce the risk of obesity in children with DS [7]. Similar results were obtained by other authors, who also observed a positive relationship between a lack of physical activity and an excessive body mass [24, 33].
The results described above lead to the conclusion that the nutritional state of children with DS is affected not only by a genetic defect and its comorbidities, but also by environmental factors, such as physical activity and dietary habits. To date, the interventions aimed at preventing obesity among children and youth with DS have usually involved developing and implementing appropriate exercise programmes. However, the research indicates that such interventions are insufficient to reduce the body mass and %BF [7]. Furthermore, it should be taken into account that the dysfunctions characteristic of DS may make increasing the physical activity not as effective for reducing excessive fat tissue in children with DS, when compared to their peers without DS [33]. In this study, the nutritional state of the children with DS may also have been affected by sociodemographic factors, such as their gender, age and the number of underage family members. Boys had a lower mean %BF than the girls. These results are consistent with those obtained by Bertapelli et al. [7] and Osaili et al. [13], who observed a higher BMI and %BF in girls with DS than in boys. A higher mean %BF in girls than in boys results from the biological changes that are characteristic of puberty [42]. Other authors have confirmed that the sexual dimorphism related to the amount and distribution of fat tissue in youth with DS is similar to the sexual dimorphism in young people without DS [43]. The results of this study also showed that the %BF decreased with each additional underage family member. Other authors have also observed an effect of the number of children in a family on the prevalence of obesity, where obesity was demonstrated to be diagnosed more frequently in children with no siblings than in children who have siblings [44, 45]. In some studies, it was found that children with no siblings showed a much lower level of physical activity compared to those who had siblings, which led to an increased risk of obesity [46, 47], because having siblings created more opportunities for active play and sport. It can also be suggested that the families with more underage members paid more attention to healthy eating and developing correct dietary habits than the families with fewer underage members. In turn, Oulmane et al. found that none of the analysed factors (gender, age, family’s socioeconomic status, parents’ education, number of meals per day and physical activity) constituted a risk factor for obesity in a population of children with DS [48].
The limitations of this study are related to the assessment of the children’s physical activity using pedometers. Since pedometers cannot measure certain forms of activity, including water sports and cycling, as well as activities that primarily involve the upper body, this may lead to an underestimation of a child’s physical activity. Furthermore, the study assessed the physical activity of all the participants using the same cut-off points that were designed for children without DS. However, no special criteria for children and youth with DS have been developed to date, and some studies suggest that the cut-off points for sitting time that were designed for typically developing children can also be used in children with DS [35].
One of the strengths of this study is the inclusion of many different factors for the analysis that may potentially affect a child’s nutritional status, i.e. diet, physical activity and sociodemographic factors. Another strength worth underlining is that the study used an objective method of assessment and a control group composed of the participants’ peers from the same environment, i.e. children attending the same schools and preschools as the participants with DS.
Conclusions
Children with DS showed an excessive BMI and %BF much more frequently than children from the control group. The share of fat in their daily energy consumption was too high in one in five of the children from both groups. The children with DS also showed an increased risk of an insufficient intake of dietary fibre and a slightly increased risk of protein deficiency. Consequently, there is a need to develop special nutritional patterns for children and youth with DS, and to educate their parents and guardians on proper nutrition.
The primary factors causing the increased risk of developing overweight and obesity, along with an increased risk of developing metabolic disorders in the future, among the children both with and without DS, were a low level of physical activity and a high intake of sucrose. The increased BMI and %BF in the children with DS may have also been caused by sociodemographic factors, including the child’s age, a female gender and fewer underage members of the family. Consequently, it is necessary to continue research on the risk factors of overweight and obesity in children with DS.
The physical activity of children with DS seems be considerably too low to effectively prevent the development of chronic diseases, due to a sedentary lifestyle. Consequently, it is necessary to develop multidirectional strategies for the prevention of overweight and obesity in children and youth with DS; in particular, it is necessary to create special intervention programmes aimed at increasing their participation in various forms of physical activity, adjusted to their capabilities.
Acknowledgments
Project financed under the programme of the Minister of Education and Science called “Regional Initiative of Excellence” in the years 2019-2023, project no. 024/RID/2018/19, amount of financing PLN 11 999 000.
Conflict of interest
The authors declare no conflict of interest.
References
1. de Graaf G, Buckley F, Skotko BG. Estimation of the number of people with Down syndrome in Europe. Eur J Hum Genet 2021; 29: 402-410.
2.
Asim A, Kumar A, Muthuswamy S, Jain S, Agarwal S. Down syndrome: an insight of the disease. J Biomed Sci 2015; 22: 41.
3.
Perkins A. The lowdown on Down syndrome. Nurs Made Incredibly Easy 2017; 15: 40-46.
4.
Li Y, Shen M, Stockton ME, Zhao X. Hippocampal deficits in neurodevelopmental disorders. Neurobiol Learning Memory 2019; 165: 106945.
5.
Verstegen RHJ, Chang KJJ, Kusters MAA. Clinical implications of immune-mediated diseases in children with Down syndrome. Pediatr Allergy Immunol 2020; 31: 117-123.
6.
McNulty M, Crispino JD. Acute megakaryocytic leukemia. Cold Spring Harbor Persp Med 2020; 10: a034884.
7.
Bertapelli F, Pitetti K, Agiovlasitis S, Guerra-Juniorb G. Overweight and obesity in children and adolescents with Down syndrome – prevalence, determinants, consequences, and interventions: a literature review. Res Develop Disabilities 2016; 57: 181-192.
8.
Zelazowska-Rutkowska B, Jakubiuk-Tomaszuk A, Cyl- wik B. Thyroid function in children with Down syndrome in the Polish population: a case-control study. Arch Iran Med 2020; 23: 386-390.
9.
Willis JR, Iraola-Guzmán S, Saus E, Ksiezopolska E, Cozzuto L, Bejarano LA, Andreu-Somavilla N, Alloza-Trabado M, Puig-Sola A, Blanco A, Broglio E, Carolis C, Hecht J, Ponomarenko J, Gabaldón T. Oral microbiome in Down syndrome and its implications on oral health. J Oral Microbiol 2020; 13: 1865690.
10.
Smarkandy MM, Mohamed BA, Al-Hamdan AA. Nutritional assessment and obesity in Down syndrome children and their siblings in Saudi Arabia. Saudi Med J 2012; 33: 1216-1221.
11.
AbdAllah AM, Raffa S, Alaidaroos T, Obaid R, Abuznada J. Nutritional status of some children and adolescents with Down syndrome in Jeddah. Life Sci J 2013; 10: 1310-1318.
12.
Basil JS, Santoro SL, Martin LJ, Healy KW, Chini BA, Saal HM. Retrospective study of obesity in children with Down syndrome. J Pediatrics 2016; 173: 143-148.
13.
Osaili TM, Attlee A, Naveed H, Maklai H, Mahmoud M, Hamadeh N, Asif T, Hasan H, Obaid RS. Physical status and parent-child feeding behaviours in children and adolescents with Down syndrome in The United Arab Emirates. Int J Environ Res Public Health 2019; 16: 2264.
14.
Pierce M, Ramsey K, Pinter J. Trends in obesity and overweight in oregon children with Down syndrome. Global Pediatric Health 2019; 6: 2333794X19835640.
15.
Yahia S, El-Farahaty RM, El-Hawary AK, El-Hussinym A, Abdel-Maseih H. Leptin, insulin and thyroid hormones in a cohort of Egyptian obese Down syndrome children: a comparative study. BMC Endocrine Disorders 2012; 12: 2-7.
16.
Ruiz AG, Gao D, Ingram DG, Hickey F, Haemer MA, Friedman NR. Does tonsillectomy increase obesity risk in children with Down syndrome? J Pediatrics 2019; 211: 179-184.
17.
Moreau M, Benhaddou S, Dard R, Tolu S, Hamzé R, Vialard F, Movassat J, Janel N. Metabolic diseases and Down syndrome: how are they linked together? Biomedicines 2021; 9: 221.
18.
Polfuss M, Simpson P, Greenley RN, Zhang L, Sawin KJ. Parental feeding behaviors and weight-related concerns in children with special needs. Western J Nurs Res 2017; 39: 1070-1093.
19.
Kułaga Z, Różdżyńska-Świątkowska A, Grajda A, Gurzkowska B, Wojtyło M, Góźdź M, Świąder-Leśniak A, Litwin M. Siatki centylowe dla oceny wzrastania i stanu odżywienia polskich dzieci i młodzieży od urodzenia do 18 roku życia. Standardy Medyczne Pediatria 2015; 12: 119-135.
20.
Stupnicki R. Relacje wagowo-wzrostowe i stosowanie wskaźnika BMI u dzieci i młodzieży. Zeszyty Naukowe WSKFiT 2015; 10: 41-47.
21.
Jarosz M, Rychlik E, Stoś K, Charzewska J (eds.). Normy żywienia dla populacji Polski i ich zastosowanie. Państwowy Zakład Higieny, Warszawa 2020.
22.
Tudor-Locke C, Hatano Y, Pangrazi RP, Kang M. Revisiting ‘‘how many steps are enough?” Med Sci Sports Exercise 2008; 40: S537-43.
23.
Lee EY, Yoon KH. Epidemic obesity in children and adolescents: risk factors and prevention. Front Med 2018; 12: 658-666.
24.
Soler Martin A, Xandri Graupera JM. Nutritional status of intellectual disabled person with Down syndrome. Nutrición Hospitalaria 2011; 26: 1059-1066.
25.
Goluch-Koniuszy Z, Kunowski M. Glycemic index and glycemic load of diets in children and young people with Down’s syndrome. Acta Scientiarum Polonorum Technologia Alimentaria 2013; 12: 181-194.
26.
González-Agüero A, Matute-Llorente Á, Gómez-Cabello A, Vicente-Rodríguez G, Casajús JA. Percentage of body fat in adolescents with Down syndrome: estimation from skinfolds. Disabil Health J 2017; 10: 100-104.
27.
Jarosz M, Sajór I, Gugała-Mirosz S, Nagel P. Węglowodany. In: Normy żywienia dla populacji Polski. Jarosz M (Eds.). Instytut Żywności i Żywienia, Warsaw 2017; 98-114.
28.
Roccatello G, Cocchi G, Dimastromatteo RT, Cavallo A, Biserni GB, Selicati M, Forchielli ML. Eating and lifestyle habits in youth with down syndrome attending a care program: an exploratory lesson for future improvements. Front Nutrition 2021; 8: 641112.
29.
Wrzochal A, Gładyś-Jakubczyk A, Suliga E. Evaluation of diet in preschool-age children with Down syndrome – preliminary examination. Medical Studies 2019; 35: 128-138.
30.
Fox B, Moffett GE, Kinnison C, Brooks G, Case LE. Physical activity levels of children with down syndrome. Pediatr Phys Ther 2019; 31: 33-41.
31.
Izquierdo-Gomez R, Martínez-Gómez D, Acha A, Veiga OL, Villagra A, Diaz-Cueto M, UP&DOWN study group. Objective assessment of sedentary time and physical activity throughout the week in adolescents with Down syndrome. The UP&DOWN study. Res Develop Disabil 2014; 35: 482-489.
32.
Forseth B, Carlson JA, Willis EA, Helsel BC, Ptomey LT. A comparison of accelerometer cut-points for measuring physical activity and sedentary time in adolescents with Down syndrome. Res Develop Disab 2022; 120: 104126.
33.
Pitetti K, Baynard T, Agiovlasitis S. Children and adolescents with Down syndrome: physical fitness and physical activity. J Sport Health Sci 2013; 2: 47-57.
34.
Wentz EE, Looper J, Menear KS, Rohadia D, Shields N. Promoting participation in physical activity in children and adolescents with Down syndrome. Phys Ther 2021; 101; 5: pzab032.
35.
Forseth B, Papanek PE, Polfuss ML. Feasibility and applicability of Evenson sedentary behavior cut points applied to children with and without intellectual and developmental disabilities. Disabil Rehabil 2022; 44: 1996-2001.
36.
Nordstrøm M, Retterstøl K, Hope S, Kolset SO. Nutritional challenges in children and adolescents with Down syndrome. Lancet Child Adolesc Health 2020; 4: 455-464.
37.
Artioli T. Understanding obesity in Down’s syndrome children. J Obesity Metabol 2017; 1: 1.
38.
Sahoo K, Sahoo B, Choudhury AK, Sofi NY, Kumar R, Bhadoria AS. Childhood obesity: causes and consequences. J Fam Med Prim Care 2015; 4: 187-192.
39.
Simmonds M, Llewellyn A, Owen CG, Woolacott N. Predicting adult obesity from childhood obesity: a systematic review and meta-analysis. Obesity Reviews 2016; 17: 95-107.
40.
Njike VY, Smith TM, Shuval O, Shuval K, Edshteyn I, Kalantari V, Yaroch AL. Snack food, satiety, and weight. Adv Nutr 2016; 7: 866-878.
41.
Dereń K, Weghuber D, Caroli M, Koletzko B, Thivel D, Frelut ML, Socha P, Grossman Z, Hadjipanayis A, Wyszyńska J, Mazur A. Consumption of sugar-sweetened beverages in paediatric age: a position paper of the European Academy of Paediatrics and the European Childhood Obesity Group. Ann Nutr Metabol 2019; 74: 296-302.
42.
Chang E, Varghese M, Singer K. Gender and sex differences in adipose tissue. Curr Diab Rep 2018; 18: 69.
43.
González-Agüero A, Ara I, Moreno LA, Vicente-Rodrí- guez G, Casajús JA. Fat and lean masses in youths with Down syndrome: gender differences. Res Develop Disabil 2011; 32: 1685-1693.
44.
Meynier A, Chanson-Rollé A, Riou E. Main factors influencing whole grain consumption in children and adults – a narrative review. Nutrients 2020; 12: 2217.
45.
Park SH, Cormier E. Influence of siblings on child health behaviors and obesity: a systematic review. J Child Fam Studies 2018; 27: 2069-2081.
46.
Kracht CL, Sisson SB. Sibling influence on children’s objectively measured physical activity: a meta-analysis and systematic review. BMJ Open Sport Exerc Med 2018; 4: e000405.
47.
Bohn C, Vogel M, Poulain T, Hiemisch A, Kiess W, Kör- ner A. Having siblings promotes a more healthy weight status-Whereas only children are at greater risk for higher BMI in later childhood. PLoS One 2022; 17: e0271676.
48.
Oulmane Z, Hilali KM, Cherkaoui M. Obesity and overweight in youth and adults with Down syndrome in Morocco: prevalence and determinants. Nutr Clin Métabol 2021; 35: 200-206.
